# test_infor

Related Tests:
C-reactive protein (CRP); fibrinogen; immunoglobulins

Why:
detect and monitor the activity of inflammation as an aid in the diagnosis of the underlying cause

When:
en your doctor thinks that you might have a condition that causes inflammation and to help diagnose and follow the course of this, especially temporal arteritis or polymyalgia rheumatica

Test General info:
ESR is an indirect measure of the degree of inflammation present in the body. It actually measures the rate of fall (sedimentation) of erythrocytes (red blood cells) in a tall, thin tube of blood. Results are reported as how many millimetres of clear plasma are present at the top of the column after one hour. Normally, red cells fall slowly, leaving little clear plasma. Increased blood levels of certain proteins (such as fibrinogen or immunoglobulins, which are increased in inflammation) cause the red blood cells to fall more rapidly, increasing the ESR.


Other Names:
Trace Minerals; Micronutrients; Essential Minerals

Related Tests:
Chromium; Copper; Caeruloplasmin; Fluoride; Iodine; Iron tests; Manganese; Molybdenum; Selenium; Zinc; Vitamin B12 and Folate; Vitamin D

Why:
detect and monitor a mineral deficiency or excess; sometimes to evaluate your nutritional status

When:
en you have symptoms or signs of a specific mineral deficiency or excess; as indicated when you have a condition that affects mineral absorption, use, or storage

Sample Type:
blood sample drawn from a vein in your arm; sometimes a random or 24-hour urine sample; rarely, a tissue sample, or another body fluid sample

Test General info:
Trace elements are a group of tests that measure specific minerals, primarily in the blood but sometimes in the urine or another bodily tissue or fluid. These minerals are substances that the body needs in tiny amounts on a regular basis for normal functioning. They enter the body through the diet and are used in the production of enzymes and hormones, the regulation of glucose, and the formation of bone, teeth, muscles, connective tissue, and blood cells. They assist in the metabolism of proteins, fats, and carbohydrates, promote wound healing, and are vital for the transport of oxygen throughout the body.Trace elements are a subset of micronutrients and essential minerals. They include:ChromiumCopperFluoride (usually included but rarely tested)IodineIronManganeseMolybdenumv Seleniumv ZincTrace element deficiencies can occur worldwide when there is insufficient food, insufficient variety of food, and/or mineral deficiencies in the soil that food is grown in. The World Health Organisation lists iodine, iron (and vitamin A) as the most important micronutrients in terms of global public health. In the United Kingdom, both deficiencies and excesses of trace minerals are rare. Deficiencies are sometimes seen with malnutrition and with conditions such as coeliac disease that are associated with decreased ability to absorb minerals. Deficiencies may occur with:Insufficient intake – such as from a restricted diet. Sometimes seen when someone receives only intravenous nutrition.Insufficient absorption – may be seen with a variety of chronic conditions associated with malabsorption and seen with surgery that removes part of the stomach or intestines.Inability to use – some people may not be able to properly utilise one or more trace elements.Increased use/need – pregnant women, children, and those that are recovering from an illness or injury may require increased nutritional support.Increased loss – an example of this is the loss of iron that occurs when red blood cells are lost due to acute or chronic bleeding.Interference/competition – an example of this is the decrease in copper that is associated with an excess of zinc.Trace element excesses may be seen with:Too much intake – this may be chronic or acute, due to taking supplements or to accidental or occupational exposure.Decreased loss – with conditions such as kidney and liver disease, the body may not be able to remove trace minerals from the body at a normal rate. With some inherited conditions, the body may store minerals in tissues and organs, resulting in damage to them. An example of this is the storage of copper seen in Wilson’s disease.


Related Tests:
Prothrombin Time (PT); activated Partial Prothrombin Time (aPTT, or PTT); D-dimer; Coagulation Factors; Thrombin Time

Why:
determine whether your fibrinogen level is adequate to allow normal blood clotting, to help diagnose disseminated intravascular coagulation (DIC), to help determine whether you have an inherited fibrinogen deficiency or abnormality. Sometimes as a non-spe

When:
en you have unexplained or prolonged bleeding, an abnormal Prothrombin Time (PT) or activated Partial Thromboplastin Time (aPTT) test, or have a relative with a hereditary fibrinogen deficiency or abnormality. To evaluate whether certain abnormalities in a Full Blood Count are due to inflammation or are self-generated. When your doctor wants additional information to help evaluate your risk of developing heart disease

Sample Type:
blood sample taken from a vein in your arm, or sometimes, via a finger prick (mainly performed in children)

Test General info:
Fibrinogen is a coagulation factor, a protein that is essential for blood clot formation. It is produced by the liver and released into the circulation as needed along with over 20 other clotting factors. Normally, when a body tissue or blood vessel wall is injured a process called the coagulation cascade activates these factors. As the cascade nears completion, soluble fibrinogen (fibrinogen dissolved in fluid) is changed into insoluble fibrin threads. These threads cross-link to form a fibrin net and then stabilise at the injury site. The net adheres there, along with aggregated cell fragments called platelets, to form a stable blood clot. This barrier prevents additional blood loss and remains in place until the area has healed.


Other Names:
Factor V Leiden mutation: Activated protein C (APC) resistance; Factor V R506Q; Prothrombin 20210 mutation: PT G20210A; factor II 20210

Formal Name:
Factor V Leiden mutation; Prothrombin G20210A mutation

Related Tests:
Antithrombin; Protein C and Protein S; Homocysteine; Methylenetetrahydrofolate Reductase (MTHFR)

Why:
determine whether you have an inherited gene mutation that increases your risk of developing a venous thromboembolism (blood clot)

When:
you have a strong family history of thrombosis associated with these mutations; if you have unexplained thrombosis that requires further investigation

Test General info:
Factor V and prothrombin are proteins that are produced in the liver and belong to a group of proteins collectively known as coagulation factors. The coagulation factors are activated in a step-by-step process called the coagulation cascade when a blood vessel is injured. The result of the coagulation cascade is formation of a blood clot which creates a barrier at the injury site, protecting it until it heals. The coagulation cascade involves many pro-coagulant proteins (such as factor V and prothrombin) as well as many anti-coagulant proteins (such as activated protein C and protein S), which act in a coordinated manner to keep the process of blood coagulation tightly regulated.Factor V Leiden is a variant form of the factor V protein that arises due to the presence of a common genetic point mutation, a change in one of the nucleotides on the gene that codes for the production of factor V protein. This altered Factor V Leiden protein activates normally to participate in stimulating blood coagulation, but resists being degraded by the anticoagulant activated protein C (APC) and thus remains active for longer than the wild type Factor V protein. The result of this resistance is an increased level of thrombin in the blood which is associated with a higher risk of venous thromboembolism (VTE).The prothrombin (PT) G20210A is a variant form of prothrombin, also caused by a common genetic point mutation. PT G20210A is also associated with an increased risk of VTE. This variant does not alter the activity or the functional properties of the prothrombin protein, but is responsible for the production of higher levels of prothrombin in individuals carrying the variant.Factor V Leiden is found at a high prevalence in the British Causcasian population, up to 1 in 10 individuals will carry the variant; its incidence varies among other ethnicities. An individual may carry one gene with the variant nucleotide alteration and one normal copy and they are described as ‘heterozygous for Factor V Leiden’ or they may, rarely, carry two copies of the variant gene and will be ‘homozygous for Factor V Leiden’. The risk of a person who is heterozygous for Factor V Leiden having a venous thromboembolism is increased by 5-10 fold and the risk of a person who is homozygous is increased around 80 fold. However, venous thromboembolism and its causes are complex and multiple and just because a person carries Factor V Leiden does not necessarily meant that they will have a venous thromboembolism.Similarly, an individual with a single variant gene copy of the PT G20210A variant is heterozygous and those who carry two copies of the variant gene are described as homozygous. The affected person will have a mild to moderate increase in their thrombin production, raising their risk of developing a VTE. PT G20210A is less common in the U.K. than factor V Leiden (about 1-2% of the general population). As with Factor V Leiden, the PT G20210A variant is more prevalent in Caucasians than in those of other ethnic backgrounds. Patients who are heterozygous for PT G20210A have a 2-3 fold increased risk of venous thromboembolism. The risks of having a venous thromboembolism in those with homozygous PT G20210A have not been established due to the rarity of this occurrence.Factor V Leiden and PT G20210A are independent mutations that are inherited separately and thus they are tested for as separate events. The testing of each is intended to identify whether or not the specific mutation is present and to determine whether the person is heterozygous or homozygous for that mutation.


Test Name:
Factor V Leiden Mutation andPT 20210 Mutation


Test Name:
Factor V Leiden mutation: Activated protein C resistance


Related Tests:
Full Blood Count, Calprotectin, Stool DNA

Why:
screen for bleeding from the gut/intestine, which may be an indicator of bowel cancer

When:
e test is used to screen for bowel cancer especially as part of the National Bowel Cancer Screening Programme. Outside of the Screening Programme the test is not widely available but it may sometimes be used when a patient has a family history of cancer of the intestine and some other organs, or to help diagnose long-term unexplained anaemia if imaging tests, such as colonoscopy, are unavailable. Patients with symptoms that are suspicious of gut cancer will usually be referred for imaging tests without having the FOB test first.

Test General info:
The faecal occult blood test (FOBT) or faecal immunological test (FIT) checks for blood in your faeces. Normally, there will not be enough blood lost through the gastrointestinal tract (stomach and intestines) to turn a FOBT positive or for you to notice it by looking. Any significant amount of blood being passed (seen as bloody or dark, tarry faeces) should be investigated.A positive FOB test will tell your doctor that you have bleeding occurring somewhere in your gastrointestinal tract. This blood loss could be due to ulcers, diverticulitis, bleeding polyps, inflammatory bowel disease, haemorrhoids (piles), from swallowed blood due to bleeding gums or nosebleeds, or it could be due to benign or malignant tumours. Anything that sticks out into the intestine, like a polyp or tumour, and is rubbed against by the faeces as it passes through, has the potential to bleed now and again. Often this small amount of blood is the first, and sometimes the only, symptom of early bowel cancer, making the FOB a valuable screening tool.


Test Name:
Faecal Occult Blood Test and Faecal Immunochemical Test


Related Tests:
Haemoglobin, Haematocrit, Red blood cell (RBC) count, White blood cell (WBC) count, White blood cell differential count, Platelet count

Why:
determine general health status and to screen for a variety of disorders, such as anaemia and infection, inflammation nutritional status and exposure to toxic substances

When:
part of a routine medical examination or as determined by your doctor

Sample Type:
blood sample taken from a vein in the arm or a finger-prick or heel-prick (newborns)

Test General info:
The full blood count (FBC) is one of the most commonly ordered tests and provides important information about the kinds and numbers of cells in the blood: red blood cells, white blood cells and platelets. Abnormalities in any of these types of cells can indicate the presence of important medical disorders. 

Blood is composed of a variety of living cells that circulate through the heart, arteries and veins carrying nourishment, hormones, vitamins, antibodies, heat and oxygen to the body`s tissues. Blood contains three main components — red blood cells, white blood cells, and platelets — suspended in fluid, called plasma. Red blood cells contain haemoglobin, a protein that carries oxygen to all the tissues of the body. Among other functions, white blood cells are responsible for protecting the body from invasion by foreign substances such as bacteria, fungi and viruses. White blood cells also control the immune process. Platelets help the blood clotting process by plugging holes in broken blood vessels.


Why:
find out whether the amount of iron in your blood is normal.

When:
rum iron blood tests are not performed routinely. Most often, serum iron levels are tested if your doctor thinks that you might have too much iron in your blood. A high iron level can be due to a genetic condition, extensive blood transfusions, or rarely due to ingestion of an overdose of iron (usually in children).Previously, serum iron was also commonly requested when iron deficiency was suspected. However, it is now recommended that the amount of stored iron (in the form of ferritin) rather than serum iron is measured to aid diagnosis of iron deficiency anaemia. Ferritin analysis gives a measure of body iron stores and is a better indicator of iron deficiency than measuring the iron in blood. However, serum iron blood tests can help to identify when anaemia is due to a long-term (chronic) illness.

Test General info:
The iron test measures the amount of iron that is circulating in the liquid part of blood bound to transferrin (a transport protein). Iron is an essential trace element in your blood. It is necessary for forming healthy red blood cells. Approximately 70% of iron absorbed from the diet is used to form haemoglobin, the protein within red blood cells which carries oxygen through your body. Iron is also used in the production of some other proteins, such as myoglobin in muscle, and various enzymes. Iron which is not used for protein production is stored within tissues as ferritin or haemosiderin.If not enough iron is taken in from the diet, then the stored levels of iron will drop. If the stored levels become depleted, this can lead to iron deficiency anaemia. On the other hand, absorption of too much iron can cause accumulation of iron stores in the tissues. This can cause damage to organs such as the heart, liver, and pancreas.


Related Tests:
Serum Iron, Ferritin; TIBC & UIBC, Transferrin; Zinc protoporphyrin; FBC; Haemoglobin; Haematocrit

Why:
evaluate your body`s current store of iron

When:
en your doctor suspects that you may have too little or too much iron in your system

Test General info:
Iron is an essential nutrient. It is needed in small quantities to help form normal red blood cells (RBCs). Iron is a critical part of haemoglobin, the protein in red blood cells that binds oxygen in the lungs and releases it as blood travels to other parts of the body. Low iron levels can lead to anaemia and the production of RBCs that are small (microcytic) and pale (hypochromic). Large quantities of iron can be toxic to the body, and absorption of too much iron over time can lead to the accumulation of iron compounds in organs and tissues. This can damage organs such as the liver, heart, and pancreas.Iron is normally absorbed from food and transported throughout the body bound to transferrin, a protein produced by the liver. About 70% of the iron transported is incorporated into the haemoglobin inside RBCs. Most of the rest is stored in the tissues as ferritin or haemosiderin. Small amounts of iron are used to produce other proteins such as myoglobin (the oxygen carrying protein in muscle), and some enzymes.Iron tests evaluate the amount of iron in the body by measuring several substances in the blood. These tests are often requested at the same time and the results considered together to help diagnose and/or monitor iron deficiency or iron overload.Iron deficiency may be seen with insufficient intake, inadequate absorption, or increased requirements, such as may be seen during pregnancy or with acute or chronic blood loss.Iron overload may be acute or chronic. Acute iron poisoning may occur, especially in children, with the ingestion of iron tablets. Chronic overload may be due to excessive intake, hereditary haemochromatosis, multiple blood transfusions or several other conditions.


Other Names:
ZPP; ZP; Free Erythrocyte Protoporphyrin; FEP

Related Tests:
Serum iron; TIBC; Ferritin; Lead; FBC; Haemoglobin; Haematocrit; Porphyrin tests; Heavy metals

Why:
screen for and monitor chronic exposure to lead; as an aid in the diagnosis of iron deficiency in children

When:
en you have been chronically exposed to lead, or when your doctor suspects lead poisoning

Test General info:
The test measures the concentration of zinc protoporphyrin (ZPP) in the blood.  ZPP is present in blood in trace amounts and is formed during the production of haem.  Concentrations of ZPP are increased in patients with lead poisoning and iron deficiency.  Haem is an essential component of haemoglobin, the protein in red blood cells (RBCs) that carries oxygen from the lungs to the body’s tissues and cells. The formation of haem occurs in a series of reactions that conclude with the insertion of an iron into the centre of a molecule called protoporphyrin. If there is not enough iron available, then protoporphyrin combines with zinc instead of iron to form zinc protoporphyrin (ZPP).  ZPP serves no useful purpose in the red blood cells since it cannot transport oxygen around the body.Lead prevents iron (but not zinc) from attaching to protoporphyrin so zinc protoporphyrin will also be elevated in severe cases of lead poisoning.ZPP is measured in two ways. The free erythrocyte protoporphyrin (FEP) test measures both ZPP (which accounts for 90% of protoporphyrin in red blood cells) and free protoporphyrin (not bound to zinc). The ZPP/haem ratio gives the proportion of ZPP compared to haem in red blood cells.


Why:
learn about the levels of iron stored in your body

When:
en your doctor suspects that  you have either too little or too much iron or too much iron in your system

Test General info:
Within cells, iron is stored as protein complexes called ferritin and haemosiderin. Ferritin is the main storage complex and is present mostly in the liver, but also in the bone marrow, spleen, and muscles. Small amounts of ferritin also circulate in the blood. The ferritin concentration within the blood stream reflects the amount of iron stored in your body.


Formal Name:
First Trimester Screen [Pregnancy-associated plasma protein-A (PAPP-A), free beta human chorionic gonadotropin (hCG) as either free beta subunit or total hCG, and nuchal translucency (NT) ultrasound]

Related Tests:
Triple Screen or Quad Screen; hCG; Amniotic Fluid Analysis; Chromosome Analysis

Why:
assess the risk of a foetus having a chromosomal abnormality, such as Down’s syndrome (trisomy 21).

When:
ually between 11 and 14 weeks of pregnancy.

Sample Type:
blood sample taken from a vein in your arm. Measurement of nuchal translucency (NT) requires a special ultrasound examination to be performed.

Test General info:
The first trimester screen is a combination of two blood tests and a special ultrasound scan that are used to assess a pregnant woman`s risk of carrying a baby with Down’s syndrome (trisomy 21). Performing and evaluating them together, along with the woman`s age, maximisesincreases both the sensitivity and specificity of the screening results.Pregnancy-associated plasma protein A (PAPP-A) is a protein produced first by the outer layer of the developing pregnancy (trophoblast) and then by the growing placenta. During a normal pregnancy, levels of this protein increase in the pregnant woman`s blood until delivery.Human chorionic gonadotropin (hCG) is a hormone produced by the developing pregnancy and then produced in large quantities by the placenta. The Free beta subunit  is used in first trimester screening. Levels usually rise rapidly in the pregnant woman`s circulation for the first 8 to 10 weeks, then decrease and stabilise at a lower level for the remainder of the pregnancy.Nuchal translucency is a measurement made during the ultrasound scan. The ultrasonagrapher measures the fluid collection between the spine and the skin at the nape of the foetus`s neck. It is a procedure that requires a specially trained sonographer, proper alignment of the foetus, and careful measurement.If the results of first trimester screening  give cause for concern, diagnostic tests (e.g.amniocentesis or chorionic villus sampling (CVS) will be recommended.


Test Name:
First Trimester Screen Down’s Syndrome Screen


Related Tests:
Ciclosporin; Therapeutic drug monitoring; Urea; Creatinine; Electrolytes; Potassium; Magnesium; Glucose

Why:
measure the concentration of tacrolimus in the blood in order to establish the correct dose, maintain therapeutic levels and detect toxic levels

When:
soon as tacrolimus therapy begins, frequently at first then at regular intervals to monitor concentrations over time

Test General info:
This test measures the amount of tacrolimus in the blood. Tacrolimus is an immunosuppressive drug that is given orally or intravenously to patients who have had a kidney, liver, heart, or other organ transplant. It is a powerful drug that helps to prevent rejection of the transplanted organ by the body. Normally, a person’s immune system would recognise the new organ as foreign and begin to attack it.  Tacrolimus limits this response and helps to prevent organ rejection by reducing the activity of certain immune cells called T-lymphocytes. 

Tacrolimus levels in the blood must be kept within a narrow therapeutic range.  If the concentration is too low organ rejection may occur, if it is too high then the person may have symptoms associated with toxicity.  Dosages must be adjusted to an individual.  Often people will begin with higher doses of tacrolimus at the start of therapy and then decrease the dose over the next few weeks.  Tacrolimus is usually taken twice a day at set intervals before or after meals.  When a person takes a dose, blood concentrations rise and peak within about 2 to 3 hours then begin to slowly fall.  The blood test is usually measured as a “trough” level.  It is timed so that the collection is 12 hours after the dose, and/or prior to the next dose – at the drug’s lowest concentration in the blood.


Other Names:
Flu PCR; rapid flu test; flu antigen test; flu subtyping

Formal Name:
Influenza nucleic acid amplification test; influenza polymerase chain reaction; rapid influenza antigen test; influenza point of care test; influenza A and B culture; influenza direct immunofluorescence test; influenza A subtype-specific PCR

Related Tests:
RSV Testing; Strep Throat Test; Pertussis Tests; Blood Culture

Why:
determine whether or not you have an influenza infection; to help doctor make treatment decisions; to help determine whether or not the flu has spread to your community; to identify the type or strain of flu virus that you have; to monitor the strains of

When:
your doctor wants to determine whether your flu-like symptoms are due to flu, another virus, or other causes. Usually only patients with severe infection are tested. When influenza is at a high level in the community, doctors will often diagnose respiratory infections as influenza based on symptoms, without taking a sample to test.

Sample Type:
ually a nose/throat swab or a nasopharyngeal aspirate

Test General info:
Influenza (the flu) is a viral infection that tends to be seasonal, beginning in late November and disappearing in early spring. It is a common respiratory (affecting the lungs) illness that causes headaches, fever, chills, muscle pains, exhaustion, a stuffy nose, sore throat, and a cough. Symptoms of flu tend to be more severe and longer lasting than the flu-like symptoms caused by the common cold. Flu and its complications can lead to hospitalisations even death, especially in the very young, the elderly, and in those with lowered immune responses or pre-existing lung disease.There are three types of influenza, known as A, B and C, each of which can change many times to create multiple strains. Influenza virus A is the most common and causes the most severe symptoms. Type B is less common and causes less severe symptoms, whilst type C usually causes only a mild illness (similar to the cold) and is usually not included in influenza tests.Flu testing relies on detecting virus that is being shed in the respiratory secretions of the person infected. Detectable virus is usually only shed for the first few days that a person is ill, so most testing must be done during this time period. Anti-viral medications have been developed to treat either influenza A alone, or both A and B. These medications, if given within 48 hours of the onset of symptoms, can reduce the severity of symptoms and reduce the time that a patient is sick by about a day. (They will not help if given later and they will not work against other viruses or against bacterial infections). These medications will only be prescribed if the person is at particular risk of complications and it is known that influenza A or B are circulating in the community. For otherwise healthy people, the treatment is to stay in bed and rest, drinking plenty of fluids, until the symptoms have cleared upFlu testing is also useful for documenting that the flu (A and/or B) has reached a community, and for identifying outbreaks in particular populations, such as a nursing home, school, or neighbourhood. Identifying these outbreaks can assist healthcare workers in the prevention and treatment of the flu throughout a community. Influenza sub-typing tests are used to determine which sub-type of flu a person has, such as H1N1 (swine flu) or H3N2 which is useful in tracking the spread of flu in a season.


Test Name:
Fluorescent antinuclear antibody , ANA ELISA


Other Names:
Vitamin B12 or Cobalamin; Folic Acid; RBC folate

Related Tests:
FBC; Methylmalonic acid (MMA); Homocysteine

Why:
help diagnose the cause of anaemia or neuropathy (nerve damage), to evaluate nutritional status in some patients, to monitor effectiveness of treatment for B12 or folate deficiency

When:
en you have large red blood cells, when you have symptoms of anaemia and/or of neuropathy. When you are being treated for B12 or folate deficiency

Test General info:
These tests measure the concentration of folate and vitamin B12 in the serum (liquid portion of the blood). The amount of folate inside the red blood cell (RBC) may also be measured - it will normally be at a higher concentration inside the cell than in the serum.B12 and folate are both part of the B complex of vitamins. Folate is found in leafy green vegetables, citrus fruits, dry beans and peas, liver, and yeast. B12 is found in animal products such as red meat, fish, poultry, milk, and eggs. In recent years fortified cereals, breads, and other grain products have also become important dietary sources of both B12 and folate (identified as ``folic acid`` on nutritional labels).Both B12 and folate are necessary for normal red cell formation, tissue and cellular repair, and DNA synthesis. B12 is also important for nerve health, while folate is necessary for cell division such as is seen in a fetus during pregnancy. A deficiency in either B12 or folate can lead to macrocytic anaemia, where red cells are reduced but macrocytic (abnormally large). Specifically a bone marrow test may show megaloblastic anaemia, where immature red cells called megaloblasts may be seen.B12 deficiency can also result in varying degrees of neuropathy, nerve damage that can cause tingling and numbness in the patient`s hands and feet. In severe B12 deficiency, a more serious nerve damage may occur known as subacute combined degeneration of the cord or SACD, where severe weakness and incoordination may occur. Subtle deterioration in eyesight and mental ability may occur. Folate deficiency in early pregnancy can cause neural tube defects such as spina bifida in a growing fetus.There are a variety of causes of B12 and/or folate deficiencies. They include: Insufficient intake
The human body stores several years’ worth of B12 in the liver. B12 is widely available in non-vegetarian foods, so a dietary deficiency of this vitamin is rare. It may be seen sometimes with general malnutrition, and in vegan vegetarians - those who do not consume any animal products including milk and eggs. It may also be seen in children and breastfed infants of vegan vegetarians. Since they do not have the stores that adults do, deficiencies in children and infants show up fairly quickly. Folate deficiency used to be common but with the advent of fortified cereals, breads, and grain products it is less so. Since folate is stored in tissue in smaller quantities than B12, folate must be consumed more regularly than B12. Malabsorption
Both B12 and Folate deficiencies may be seen with conditions that interfere with their absorption in the small intestine. These may include: Coeliac disease  Bacterial overgrowth in the stomach and intestines Reduced stomach acid production (stomach acid is necessary to separate B12 from the protein in food) Pernicious anaemia , the most common cause of B12 deficiency. Normally a molecule called intrinsic factor is made by parietal cells that line the stomach. B12 binds to intrinsic factor in the stomach, and the resulting complex is absorbed in the intestines. With pernicious anaemia, antibodies attack parietal cells, reducing intrinsic factor production, or attack intrinsic factor, blocking its action, in either case preventing the efficient absorption of B12. Surgery that removes part of the stomach (and the parietal cells) or the intestines may greatly decrease absorption Increased loss
This may be seen with:Liver and kidney disease Alcoholism, with alcohol abuse less B12 and folate are absorbed and more are excreted from the kidneys Anti-seizure medications such as phenytoin can decrease folate as can drugs such as metformin and methotrexate Increased need
All pregnant women need increased amounts of folate for proper fetal development. If a woman has a folate deficiency prior to pregnancy, it will be intensified during gestation, and may lead to premature birth and neural tube defects in the child.


Why:
evaluate the function of your pituitary gland, which regulates the hormones that control your reproductive system

When:
you are having difficulty getting pregnant or are having irregular menstrual periods (in order to identify or rule out ovarian failure/menopause in women and sperm production failure in men); if your doctor thinks that you have symptoms of a pituitary, ovarian, testicular or hypothalamic disorder; when your doctor suspects that a child has delayed or earlier than expected sexual maturation (or delayed or early growth).

Test General info:
Follicle-stimulating hormone (FSH) is made by the pituitary gland in the brain. Control of FSH production is a complex system involving hormones, such as gonadotrophin-releasing hormone (GnRH) produced by the gonads (ovaries or testes), the pituitary gland, and the hypothalamus.In women, FSH stimulates the growth and development of ovarian follicles (unfertilised eggs) during the follicular phase of the menstrual cycle. This cycle is divided into two phases, the follicular and the luteal, by a mid-cycle surge of FSH and luteinising hormone (LH). Ovulation (release of the egg from the ovary) occurs shortly after this mid-cycle surge of hormones. During the follicular phase, FSH initiates the production of oestradiol by the follicle, and the two hormones work together in the further development of the egg follicle. During the luteal phase, FSH stimulates the production of progesterone. Both oestradiol and progesterone help the pituitary control the amount of FSH produced. At the time of the menopause, the ovaries stop functioning and FSH levels rise. During pregnancy, oestrogen levels are high and this makes FSH undetectable.In men, FSH stimulates the testes to produce mature sperm. FSH levels are relatively constant in men after puberty.In infants and children, FSH levels rise shortly after birth and then fall to very low levels (by 6 months in boys and 1-2 years in girls). At about 6-8 years, levels again rise with the beginning of puberty and the development of secondary sexual characteristics.


Why:
diagnose hypothyroidism or hyperthyroidism in adults and to monitor response to treatment

When:
en you have symptoms of an underactive (hypothyroidism) or overactive (hyperthyroidism) thyroid gland

Test General info:
This test measures free thyroxine, or FT4, in your blood.  Thyroxine is one of two major hormones produced by the thyroid gland (the other is called triiodothyronine (T3)). Within the blood, most thyroid hormones are attached to a protein, but it is the hormones that are free from these proteins that are able to affect body functions.  This is therefore why we measure the `free` thyroxine in your blood sample.  The thyroid gland is found in the neck, in front of the windpipe.Thyroxine (T4) makes up nearly all of what we call thyroid hormone, while triiodothyronine (T3) makes up less than 10%. Thyroid hormones help regulate the body’s metabolism (that is, how the body functions).Most T4 in blood is attached to a protein; less than 1% is unattached. The blood test can measure either the total (both bound and unattached, TT4) or free (unattached, FT4) T4 hormone in your blood.Scientists believe that free hormone is responsible for all the effects of thyroid hormone.


When:
you get an abnormal TSH , T4 or FT4 result

Test General info:
The test measures the amount of free triiodothyronine, or FT3, in your blood.T3 is one of two major hormones produced by the thyroid gland (the other hormone is called thyroxine, or T4). The thyroid gland is found in the neck, in front of the windpipe. T3 makes up less than 10% of what we call thyroid hormone, while T4 makes up the rest. T3, however, is about four times as strong as T4, and is thought to cause most, if not all, the effects of thyroid hormones.Many of your body’s cells can turn T4 into T3; T4 may be mainly a ``reservoir`` used to make T3 available.Thyroid hormones help regulate the body’s metabolism(how the body functions).About 99.7% of T3 in blood is attached to a protein, and the rest is unattached (free). Blood tests can measure either the total (both bound and unattached) or free  T3 hormone in the blood. These tests are called TT3 (total T3), and FT3 (free T3) respectively.


Other Names:
Glycated Serum Protein (GSP); Glycated Albumin

Why:
help monitor your diabetes over time, especially if it is not possible to monitor using the HbA1C test; to help determine the effectiveness of changes to your diabetic treatment plan

When:
en you are diabetic and your doctor wants to evaluate your average blood glucose level over the last 2-3 weeks

Test General info:
The fructosamine test is a measurement of glycated protein, mainly albumin. When glucose levels in the blood are elevated over a period of time, glucose molecules permanently combine with proteins in the blood in a process called glycation. Affected proteins include albumin, the principal protein in the blood, other serum proteins, and hemoglobin, the protein found inside red blood cells (RBCs). The more glucose that is present in the blood, the greater the amount of glycated protein and haemoglobin formed. These combined molecules persist for the life of the protein or RBC and provide a record of the average amount of glucose that has been present in the blood over that time period.Since RBCs live for about 120 days, glycated haemoglobin (haemoglobin A1C) represents average blood glucose levels over the past 2 to 3 months. Serum proteins have a shorter lifespan, about 14 to 21 days, so glycated proteins, and the fructosamine test, reflect average glucose levels over a 2 to 3 week time period.Keeping blood glucose levels as close as possible to normal helps patients with diabetes to avoid many of the complications and progressive damage associated with elevated glucose levels. Good diabetic control is achieved and maintained by daily (or even more frequent) self-monitoring of glucose levels and by monitoring of the effectiveness of treatment using either a HbA1C or, occasionally, a fructosamine test.


When:
you have symptoms of a syphilis infection, if you have another STD, or are pregnant

Test General info:
The test is looking for evidence of Treponema pallidum, the bacterium that causes syphilis. Syphilis is a sexually transmitted disease. It is easily treated but can cause severe health problems if left untreated.


Formal Name:
Potassium hydroxide preparation, Fungal culture, Fungal antigen and antibody tests, and Calcofluor white stain

Related Tests:
AFB smear and culture, CSF analysis, Susceptibility testing, Gram stain, Bacterial wound culture

Why:
detect a fungal infection, to determine which specific fungus or fungi are present, and sometimes to isolate and grow the fungi for subsequent susceptibility testing

When:
en the doctor suspects that you have a skin, lung, or systemic fungal infection; sometimes after treatment to monitor its effectiveness

Sample Type:
e sample collected depends upon the suspected location(s) of the infection. It typically includes: scrapings of the skin, nail and hair samples, fluids, blood, and/or a tissue biopsy.

Test General info:
Fungi are microorganisms that exist in nature as either yeast or moulds. There are more than 50,000 species of fungi in the environment, but less than 200 species are associated with human disease. Of these, only about 20 to 25 species are common causes of infection.Fungal infections represent the invasion of tissues by one or more species of fungi and range from superficial skin infections to serious deep tissue, blood, lung or systemic diseases. Superficial fungal infections are very common. They may cause nail infections or itchy red scaly skin infections such as those commonly known as athlete’s foot, ringworm, yeast infections that cause white patches in the mouth (thrush) or vaginal itching and discharge. According to the Centres for Disease Control and Prevention (CDC), almost 75% of women will have at least one yeast infection in their lifetime.Less commonly, fungi may spread from their original location to penetrate to deeper tissues or may cause serious lung infections, blood infections (septicaemia), or systemic infections that can affect any organ in the body. While anyone can get a serious lung or systemic fungal infection, most affected people will only experience mild to moderate flu-like symptoms. However, people that are immunocompromised, such as those with HIV/AIDS, those who have had an organ transplant, and those with an underlying condition such as diabetes or lung disease are at an increased risk of having a severe fungal infection, a systemic infection, and/or recurrent infections.Fungal tests are used to detect and identify fungi in order to diagnose infections and help guide their treatment. Fungal testing typically includes a microscopic examination of the sample on a slide, sometimes using a preparation or stain to aid in detection of fungal elements. This may be sufficient to determine that the infection is due to a fungus and, with superficial infections; no more tests may be required. However, in cases of persistent, deep, or systemic infections when a more definitive diagnosis is needed, it may be followed by additional tests such as culture and susceptibility testing, antigen, and/or antibody tests.


Related Tests:
FBC; Blood film; Reticulocyte count; Bilirubin; RBC count; Haemoglobin; Autohaemolysis test; Heinz body stain

Why:
see whether you have an inherited deficiency of Glucose-6-Phosphate Dehydrogenase (G6PD), necessary to keep red blood cells healthy

When:
a child has long term jaundice as a newborn and no other cause can be identified; when you have had one or more bouts of haemolysis (break-up of red blood cells, which may cause jaundice, dark urine or anaemia), particularly if the haemolysis follows ``oxidative`` stress caused by some medicines, foods, or infections

Test General info:
This test measures the amount of G6PD in the red blood cells (RBCs). G6PD is an  enzyme that protects red blood cells from the effects of oxidation. If there is insufficient G6PD, the RBCs become more vulnerable to oxidative damage. If these RBCs are exposed to an oxidative agent (for a list, click here), it changes their cellular structure, precipitating solid lumps of haemoglobin inside the cells (Heinz Bodies), causing the red cells to break up (”haemolyse”).G6PD deficiency (one of the most severe forms is called Favism – people with this variant are at risk if they eat broad - “fava” - beans) is the most common enzyme deficiency in the world, affecting about 400 million people. It may be seen in up to 20% of the population in Africa, 4-30% in the Mediterranean, and in Southeast Asians. Mutations or changes in the G6PD gene may lead to the production of a G6PD enzyme that has reduced performance or stability. This is expressed as decreased enzyme activity levels.So far, more than 440 G6PD gene variations have been found and can cause enzyme activity deficiencies of varying severity depending on the particular mutation and on the individual person. The G6PD gene is located on the X chromosome. Since males have one X and one Y chromosomes, a single X chromosome carrying the faulty G6PD gene with no additional healthy X chromosome will result in G6PD deficiency. Females have two X chromosomes, thus two copies of the G6PD gene could possibly be inherited.  Heterozygous females (those with only one altered gene) can produce enough normal G6PD that they usually do not experience any symptoms. However, the presence of the abnormal form may be identified if the deficiency is detected in their male children. Rarely, a female may be homozygous, having two altered G6PD genes (the same or different mutations), and thus will experience G6PD deficiency.In newborns, G6PD deficiency may cause long term and unexplained  jaundice. Left untreated, this jaundice can lead to brain damage and mental retardation.Most people with G6PD deficiency can lead fairly normal lives, but they must be cautious to avoid certain medications and other triggers, includingAspirin (may be tolerated, depending on which type of G6PD abnormality is present)Antibioticso  Chloramphenicol, Dapsone, Nitrofurantoin, Quinolones (e.g. ciprofloxacin), Sulphonamides (e.g. co-trimoxazole or Septrin)Antidiabetic medicationo  GlibenclamideAnti-gout medicationso ProbenecidAntimalarialso Quinine, Chloroquine, Pamaquine, PrimaquineChemotherapyo Doxorubicin (“Adriamycin”)Methylene blueSulfasalazine, mesalazineVitamin KCertain FOODSo Broad (“fava”) beans, Mangetout (“snow peas”)CHEMICAL SUBSTANCESo  naphthalene, found in moth ballsThese triggers can cause oxidative stress resulting in a haemolytic crisis. Infections, either bacterial or viral, can also cause oxidative stress and lead to bouts of haemolytic anaemia. With haemolytic anaemia, RBCs are destroyed at an accelerated rate and the patient becomes pale and fatigued (anaemic) as their capacity for providing oxygen to their body decreases. In some cases, jaundice can also be present during episodes of haemolysis. Most of these episodes are self-limiting, but if a large number of RBCs are destroyed and the body cannot replace them fast enough, then the affected patient may require a blood transfusion or even develop kidney problems. A small percentage of those affected with G6PD may experience chronic anaemia.


Related Tests:
AST; ALT; ALP; bilirubin; liver function tests (LFTs)

Why:
screen for liver disease or alcohol abuse; and to help your doctor tell whether a raised concentration of alkaline phosphatase (ALP) in the bloodstream is due to liver or bone disease

When:
your doctor thinks that you have symptoms of a liver disorder/disease

Test General info:
Gamma-glutamyl transferase (GGT) is an enzyme found mainly in the liver. When the liver is injured or the flow of bile is obstructed, the concentration of GGT within the bloodstream rises. It is therefore a useful marker for detecting bile duct problems.


Why:
detect an overproduction of gastrin, to help diagnose Zollinger-Ellison syndrome (ZE syndrome), to help diagnose multiple endocrine neoplasia type 1 (MEN-1) and to monitor for recurrence of a gastrin-producing tumour (gastrinoma)

When:
en you have peptic ulcers and/or diarrhoea and abdominal pain that your doctor suspects is caused by excess gastrin; periodically to monitor for a gastrinoma recurrence

Test General info:
This test measures the amount of gastrin in the blood. Gastrin is a hormone that regulates the production of acid in the stomach. It is produced by special cells called G-cells in the stomach during the digestive process. When food is eaten, the stomach becomes less acidic, promoting gastrin production. Gastrin in turn stimulates parietal cells to produce stomach acid. As acidity increases in the stomach, food is broken down and gastrin production falls. This feedback system normally results in low to moderate levels of gastrin in the blood. Rare conditions such as G-cell hyperplasia and Zollinger-Ellison (ZE) syndrome can cause an overproduction of gastrin and stomach acid. These conditions can lead to peptic ulcers that can be difficult to treat.ZE syndrome is characterised by high gastrin levels, greatly increased stomach acid production, and by peptic ulcers due to gastrin-producing tumours called gastrinomas. Gastrinomas can form in the pancreas, the duodenum and rarely in other parts of the body. More than half of these tumours are malignant - causing cancer that can spread to other parts of the body, such as the liver. Even tiny tumours can produce large quantities of gastrin.


Why:
screen for infection with HPV, some types of which are associated with cervical cancer

When:
you are sexually active, have symptoms of HPV infection (genital warts), or have an irregular cervical smear test

Test General info:
The test is looking for evidence of infection by human papilloma virus (HPV), a virus that can cause skin warts and genital warts (also called condylomata) and that has been linked to cervical, penile, and other forms of genital cancer.


Why:
determine if you have had a recent or past infection with the rubella virus, or to check that you are protected from the rubella virus

When:
you plan to get pregnant or have symptoms of rubella infection

Sample Type:
blood sample taken from a vein in the arm (this may need to be repeated after 7 days), oral fluid, a throat swab, or other more invasive samples such as amniotic fluid depending on symptoms.

Test General info:
Rubella is a viral infection that causes a fine red rash and flu-like symptoms, such as a high temperature, headache and a general feeling of being unwell. The raised red rash appears first on the face and neck and travels to the body and limbs. Teenagers and adults may experience more severe symptoms, such as joint pains, which may last several weeks. Rubella is usually harmless and the patient gets better without any special treatment, but when a woman gets rubella in the first three months of her pregnancy, serious birth defects, miscarriage, or stillbirth may result.You may be infected when you come into contact with the nasal or throat secretions of someone who has an active viral infection. If you catch rubella, you are infectious one week before the rash appears and one week after. In children, rubella infections generally produce mild symptoms. The number of new cases of rubella is low in the UK since a combined vaccine for measles, mumps, and rubella (MMR) is recommended for all children.The test, which can be done at any time, will provide the necessary information about a person’s immunity to the virus.


Other Names:
GH; Human Growth Hormone (HGH); Somatotropin

Related Tests:
IGF-1 (Insulin-like growth factor-1; also called Somatomedin C); GHRH (Growth Hormone Releasing Hormone); Glucose Tolerance Test; Cortisol; ACTH; TSH; Glucose; Prolactin

Why:
identify diseases and conditions caused by either a deficiency or overproduction of growth hormone (GH), to evaluate pituitary function, and to monitor the effectiveness of GH treatment

When:
part of an evaluation of pituitary function. Slow growth in stature, delayed development (in children), decreased bone density and/or muscle strength, and increased lipids (in adults) all could be related to insufficient GH production. Symptoms suggestive of gigantism in children or acromegaly in adults may be a result of excess GH production

Sample Type:
ually several blood samples are taken at timed intervals from veins in your arm. Sometimes a single sample of blood is required following a fast or after a period of strenuous exercise

Test General info:
Growth hormone (GH) is essential for a child’s normal growth and development and promotes proper long bone growth from birth through puberty. Children with insufficient GH production grow more slowly and are smaller in size for their age; one of the first symptoms of growth hormone deficiency (GHD). It should be noted that short stature in itself can also be related to familial traits or other genetic disorders.  Constitutional delay (i.e. temporary delay in growth) is the most common cause of short stature in childhood.Excess GH is most often due to a benign GH-secreting pituitary tumour. Too much GH can cause children’s long bones to continue to grow beyond puberty, resulting in gigantism with heights of over 2.1 meters. Those with excess GH may also have thickening of facial features, general weakness, delayed puberty, and headaches. 

Although GH is not as active in adults, it does play a role in regulating bone density, muscle mass, and lipid metabolism. Deficiencies can lead to decreased bone densities, lower muscle mass, and altered lipid concentrations. Excess GH in adults can lead to acromegaly, marked not by bone lengthening but by bone thickening. Although symptoms such as skin thickening, sweating, fatigue, headaches, and joint pain can be subtle at first, increased GH concentrations can lead to enlarged hands and feet, enlarged facial bones, carpal tunnel syndrome (trapped nerves), and abnormally enlarged internal organs. If untreated, acromegaly in adults and gigantism in children can lead to complications such as type 2 diabetes, increased cardiovascular disease risk, high blood pressure, arthritis, and in general, a decreased life span. GH stimulation and suppression tests are most often used to diagnose GH abnormalities. Since growth hormone is released by the pituitary gland in bursts throughout the day, random measurements of GH levels are not usually of use clinically.


Why:
monitor a person’s diabetes and to help treatment decisions. It can also be used to diagnose type 2 diabetes.

When:
en first diagnosed with diabetes and then at least twice a year

Test General info:
Some of the glucose in your blood binds to haemoglobin (the protein that carries oxygen in your red blood cells). This combination of glucose and haemoglobin is called haemoglobin A1c (HbA1c). The amount of HbA1c formed is directly related to the average concentration of glucose in your bloodstream. Red blood cells live for 2–3 months, and because of this, the amount of HbA1c in your blood reflects the average level of glucose in your blood during the last 2-3 months. If your diabetes is not well controlled, your blood glucose levels will be high, causing higher HbA1c levels.


Why:
screen for Neisseria gonorrhoeae, which causes the sexually transmitted disease (STD) gonorrhoea

When:
you have symptoms of gonorrhoea or are pregnant

Sample Type:
swab of secretion or discharge from the infected area.Testing is available at genito-urinary medicine (GUM) clinics , sexual health centres, contraceptive centres and some GP surgeries.

Test General info:
The test is looking for evidence of the bacterium Neisseria gonorrhoeae, which causes the sexually transmitted disease gonorrhoea. Gonorrhoea is easily treated but can cause severe reproductive and health problems if left untreated.


Related Tests:
Cholesterol; Non-HDL; LDL; Triglycerides; Lipid profile; Cardiac Risk Assessment

When:
ed 40 as part of a routine cardiovascular health check, or if you are already thought to be at risk of cardiovascular disease for another reason.

Sample Type:
blood sample taken from a vein in the arm or from a finger-prick

Test General info:
HDL is one of the classes of lipoproteins that carry cholesterol in the blood. HDL is thought to be beneficial because it removes excess cholesterol from tissues and carries it to the liver for disposal. Hence HDL cholesterol is often called “good” cholesterol. The test for HDL measures the amount of cholesterol carried on HDL particles in blood.


Related Tests:
Susceptibility Testing, Bacterial Wound Culture, Blood Culture, CSF Analysis, Urine Culture, AFB Smear and Culture, Gonorrhoea, Stool Culture, Fungal Tests, Sputum Culture, Synovial Fluid Analysis, Pleural Fluid Analysis, Pericardial Fluid Analysis, Perit

Why:
identify the cause of a bacterial infection so appropriate treatment can be given

When:
your doctor suspects that you have a bacterial infection

Test General info:
A Gram stain is used to determine if bacteria are present in an area of the body that is normally sterile, such as spinal fluid. A sample from the infected area is smeared on a glass slide and allowed to dry. A series of stains are applied and then the stained slide is examined under a microscope where bacteria appear either purple (gram positive) or pink (gram negative). The test is named for Dr. Christian Gram, who invented the process.A Gram stain can predict the type of bacteria causing an infection, such as pneumococcal pneumonia or a staphylococcal abscess. Viruses cannot be seen with a Gram stain since they lack the cell wall, which takes up the stain.


Formal Name:
Group A streptococcus; Group A beta haemolytic streptococcus; streptococcus pyogenes

Why:
diagnose a possible bacterial infection of the throat (usually Streptococcus pyogene)

When:
you have a sore throat and fever and your doctor thinks it may have a bacterial cause (although most sore throats are caused by viruses and won`t require antibiotics)

Test General info:
The test identifies Streptococcus pyogenes, known as Group A streptococcus, which are bacteria that infect the back of the throat and are a common cause for an infected and sore throat. Whilst group A Streptococcus is the commonest bacterial cause of a severe sore throat (pharyngitis), it is not the only bacterial cause and others include group C and G streptococcus and arcanobacteria.


Other Names:
H. pylori antibody test; H. pylori antigen test; H. pylori breath test

Why:
diagnose an infection with Helicobacter pylori that can cause peptic ulcers

When:
you have gastrointestinal pain or symptoms of an ulcer

Sample Type:
stool sample, blood sample from a vein, tissue biopsy of the stomach lining, or a breath test

Test General info:
These tests are looking for evidence of an infection in your gastrointestinal tract by a bacterium, known as Helicobacter pylori. This bacterium is known to be a major cause of peptic ulcer disease. H. pylori is also associated with the development of gastric (stomach) cancer.


Related Tests:
Full Blood Count, Haemoglobin, RBC Count, Blood Film, Iron Tests, Reticulocyte Count, Vitamin B12 and Folate, Bone Marrow Aspiration and Biopsy, G6PD, Erythropoietin, Haemoglobin Variants

Why:
your doctor suspects that you have anaemia (too few red blood cells), polycythaemia (too many red blood cells), or dehydration

When:
part of a full blood count (FBC), a general blood screening test which may be requested for a variety of reasons

Sample Type:
blood sample taken from a vein in your arm or by a finger-prick (children and adults) or heel-prick (newborns)

Test General info:
Blood is a mixture of cells and plasma. The packed cell volume (PCV) is a measurement of the proportion of blood that is made up of cells. The value is expressed as a percentage or fraction of cells in blood. For example, a PCV of 40% means that there are 40 millilitres of cells in 100 millilitres of blood. 

Red blood cells account for nearly all the cells in the blood. The PCV rises when the number of red blood cells increases or when the total blood volume is reduced, as in dehydration. The PCV falls to less than normal, indicating anaemia, when your body decreases its production of red blood cells or increases its destruction of red blood cells.


Related Tests:
Full blood count, haematocrit, mean corpuscular haemoglobin concentration (MCHC), mean corpuscular haemoglobin(MCH)

Why:
you have anaemia (too few red blood cells) or polycythaemia (too many red blood cells), to assess its severity, and to monitor response to treatment

Sample Type:
blood sample collected from a vein in your arm or by a finger-prick (children and adults) or heel-prick (newborns)

Test General info:
This test measures the amount of haemoglobin (a protein found in red blood cells) in your blood and is a good indication of your blood`s ability to carry oxygen throughout your body. Haemoglobin carries oxygen to cells from the lungs. If your haemoglobin levels are low, you have anaemia, a condition in which your body is not getting enough oxygen, causing fatigue and weakness. If your haemoglobin levels are high, this usually means you have too many red cells which is called polycythaemia. Polycythaemia, when severe, can cause the blood to become too viscous, leading to heart failure, heart attacks or strokes.


Related Tests:
Haemoglobin Electrophoresis; Isoelectric Focusing; Haemoglobin S Solubility; Haemoglobin Fractionation by HPLC; Haemoglobinopathy Evaluation, Full Blood Count, Blood Film, Iron Tests

Why:
screen for the presence of sickle cell trait or to confirm the presence of sickle cell disease

When:
you are of Afro-Carribean descent to determine if you carry one or both genes for sickle cell disease and for antenatal screening. There are other ethnic minorities in whom the sickle gene is found and should be tested if index of clinical suspicion is high.

Sample Type:
blood sample taken from a vein in the arm. In children, a blood sample from a finger-prick or heel-prick

Test General info:
Blood is tested for the presence of Haemoglobin S (HbS), which is a genetic variant of the protein haemoglobin. Haemoglobin is found inside red blood cells (RBCs) and is responsible for carrying oxygen from the lungs to all of the tissues and organs of the body. Normally haemoglobin exists in various forms (Haemoglobin A, Haemoglobin A2, and Haemoglobin F) that are present in different amounts. One genetically abnormal haemoglobin is known as HbS, which causes the RBC to change shape and affects its ability to carry oxygen. In sickle cell disease, one abnormal HbS gene is inherited from each of the parents. The RBC in these individuals change shape, thus affecting the ability of the red cells to carry oxygen.


Related Tests:
FBC; Reticulocyte count; Blood film; Haemoglobin; Haematocrit; Bilirubin; Direct antiglobulin test

Why:
help detect and evaluate haemolytic anaemia

When:
en you have signs of jaundice, or of anaemia such as weakness, paleness, or breathlessness that the doctor suspects may be due to red blood cell destruction (haemolytic anaemia)

Test General info:
This test measures the amount of haptoglobin in the blood. Haptoglobin is a protein produced by the liver. Its purpose is to find and attach itself to free haemoglobin in the blood. This forms a complex that is rapidly removed from the circulation by the liver and the iron is then recycled. Haemoglobin is a protein that transports oxygen throughout the body. It is normally found inside red blood cells (RBCs); very little is found free, except when RBCs are destroyed and their haemoglobin is released. When large numbers of RBCs are destroyed, haptoglobin concentrations in the blood will temporarily decrease as the consumption of haptoglobin exceeds that produced by the liver.Increased RBC destruction may be due to inherited or acquired conditions that cause haemolysis of RBCs. Causes of haemolysis include: transfusion reactions, certain drugs, and/or mechanical breakage, such as may be seen with some artificial heart valves. Acquired haemolysis may also result from dysregulation of the immune system causing the body to destroy its own cells. The destruction may be mild or severe, acute or chronic, and it can lead to haemolytic anaemia. Patients with haemolytic anaemia may experience symptoms such as tiredness, weakness, and shortness of breath and their skin may be pale or jaundiced.Liver disease  may also result in low haptoglobin levels as liver damage may reduce both the production of haptoglobin and the removal of the haptoglobin-haemoglobin complexes.


Test Name:
HCV, Hepatitis C antibody, Anti-HCV, Hepatitis C viral load, HCV-RNA

Other Names:
HCV, Hepatitis C antibody, Anti-HCV, Hepatitis C viral load, HCV-RNA

Related Tests:
Hepatitis A; Hepatitis B; Viral hepatitis panel/screen, Liver function tests (LFT’s) eg ALT, AST, GGT, Bilirubin

Why:
screen for and diagnose a hepatitis C virus infection and to monitor treatment of the infection

When:
you may have been exposed to/have risk factors for the hepatitis C virus, such as through contact with infected blood, sexual relations with an infected person, IV drug use or you have symptoms associated with liver disease

Test General info:
Hepatitis C is a virus that can infect and damage the liver. In most cases, it is contracted through exposure to blood (usually from sharing contaminated needles while injecting drugs or, before 1992, through a blood transfusion), through sex with an infected person, via healthcare occupational exposure and it can also be passed from mother to baby.Many people who are infected with Hepatitis C are not aware they are as acute infection produces few to mild non-specific symptoms. However Hepatitis C can also exist as a chronic (longstanding) infection and you can show no signs of this for a number of years (even decades) but it can then cause significant liver damage. About 65-75% of those infected can develop chronic liver disease with 20-30% of these developing cirrhosis over many years.Hepatitis C antibody is produced by the body in response to exposure to the hepatitis C virus (HCV). The most common test for HCV looks for these antibodies in your blood. Some first line tests are also looking for the hepatitis C antigen, which the virus itself produces, as well as your antibody response. Other tests detect the presence of and actual amount of virus present or determine the specific subtype of virus.


Related Tests:
Lead, Mercury, Arsenic, Chromium, Cobalt, Iron, Copper

Why:
screen for, detect, and monitor excessive exposure to specific heavy metals

When:
riodically when you work with heavy metals, or when your doctor suspects that you may have been exposed. If you have a metal-on-metal hip prosthesis, depending upon the size and type of implant, you may need annual blood monitoring of metal ions (e.g. chromium and cobalt). Consult your doctor for further advice.

Sample Type:
blood sample taken from a vein in your arm or a 24-hour urine sample; rarely, a hair sample, tissue sample, or other body fluid sample

Test General info:
A heavy metals panel is a group of tests that measures the quantity of specific, potentially toxic metals in the blood, urine, or more rarely in the hair or other body tissue or fluid. A laboratory may offer several different groupings of heavy metals panels as well as tests for individual metals. The most common combination includes lead, mercury, and arsenic. Other panels may include one or more additional metals, such as cadmium, copper, or zinc. For hip replacement monitoring, the panel includes chromium and cobalt. A doctor will select which metals to test for based upon what a person may have been exposed to in addition to clinical symptoms.The term ``heavy metals`` is loosely defined. It is related to the periodic table of elements and refers to a variety of elements with high density or metallic properties. These elements are found naturally throughout the environment and are also used by industries to manufacture a wide range of common products. Some of them, such as iron, copper, selenium, molybdenum, and zinc, are required in trace amounts by the body for normal function but can be toxic at higher levels. Significant concentrations of any of the heavy metals can be irritating or damaging to the body and can contaminate soil, air, food, and water, persisting indefinitely in the environment. Because they are a source of potential injury, the term ``heavy metals`` is frequently used interchangeably with the term ``toxic metals.``The signs and symptoms that a person may experience depend upon the type of metal, its form, the quantity, the length of exposure, the type of exposure, the age of the person, and the person`s general state of health. Some metals are much more toxic than others, and one form of a metal may be more harmful than other forms. How a person is exposed can influence the amount of metal absorbed and the part(s) of the body that are affected. For example, a metal that does little when it is held in someone`s hand, or is only moderately harmful and poorly absorbed when swallowed, may be much more toxic and cause severe lung damage when its vapours are inhaled.Severe acute exposure can cause damage and, in some cases, can be life-threatening, but moderate exposures over time should also be monitored. The body is able to process small amounts of heavy metals, but moderate to large quantities can accumulate in the kidneys, liver, bones and brain. Some metals are considered carcinogenic – they increase the risk of developing cancer – and some can affect the body`s ability to produce red and white blood cells. Unborn and young children are at the highest risk because exposures to low or moderate concentrations can affect physical and mental development and can permanently damage the organs and brain. Many of the metals can be passed from the mother to the foetus, and some can be passed to the infant in breast milk.


Other Names:
Herpes Culture; Herpes Simplex Viral Culture; HSV DNA; HSV by PCR; HSV-1 or HSV-2 IgM or IgG; HSV-1; HSV-2; HHV1; HHV2

Why:
screen for or diagnose infection with herpes simplex virus

When:
you have symptoms of an infection with herpes simplex virus

Sample Type:
swab or scraping from a blister or sore in the infected area

Test General info:
The test is looking for evidence of infection by herpes simplex virus, a common sexually transmitted disease that causes small blisters (vesicles) on the mouth or genitals. The blisters seen around the oral cavity and in the mouth are commonly called “cold sores” and are evidence of active herpes infection.


Other Names:
Mononucleosis spot test; mononuclear heterophil test; heterophil antibody test; Mono test

Related Tests:
Tests for antibodies to Epstein-Barr virus (EBV) antigens, Paul-Bunnell test

Why:
get screened for infectious mononucleosis (glandular fever).

When:
you have symptoms of mononucleosis, including fever, sore throat, swollen glands, and fatigue. (The monospot test is not useful to detect EBV in children.)

Test General info:
The Monospot test detects heterophil antibodies. It detects a reaction with horse red blood cells. A similar test, the Paul-Bunnell test, detects a reaction with sheep red blood cells. The antibodies are made in response to an infection by Epstein-Barr virus (EBV). EBV causes infectious mononucleosis (glandular fever), a self-limiting disease. 

Mononucleosis is characterised by the presence of atypical white blood cells (atypical lymphocytes) in an infected person. Patients have these symptoms: fever, sore throat, swollen glands, and fatigue. About 70%–80% of patients with infectious mononucleosis produce these heterophil antibodies, which are not specific for EBV infection but are a good predictor of EBV infection.


When:
en you have symptoms of mercury poisoning, to evaluate a known exposure to mercury, or to monitor occupational exposure to mercury

Sample Type:
blood sample taken from a vein in your arm and/or a urine collection

Test General info:
Mercury is an element that exists in three forms:Metallic or elemental mercury. This form can be found in dental fillings, some thermometers and batteries.Inorganic mercury where it has combined with other elements such as oxygen or sulphur to form a salt.Organic mercury where it has combined with carbon to form a variety of organic compounds, the most common of which is methyl mercury. This form can be found in larger, older predator fish such as sharks and king mackerel due to bioaccumulation in the food chain.This test measures the amount of mercury in blood, urine, or (rarely) hair to detect acute or chronic excessive exposure.Mercury is found in small quantities throughout the environment.  It is released by the breakdown of minerals in rocks and soils and as a by-product of fossil fuel combustion and waste incineration. It is inhaled with the air that we breathe, absorbed through the skin, and ingested with food.  The tiny amounts to which the vast majority of people are exposed to do not generally cause health concerns but people who are exposed to dangerous concentrations of mercury (such as might be found at a hazardous waste site) or are exposed chronically to mercury (such as those who work with “heavy metals” in their occupation) may have mercury-related symptoms and complications.Exposure to excessive amounts of mercury can be toxic.  The amount of mercury absorbed by an individual and its effects on their health depends on the type of mercury, its concentration, and the exposure time.  According to the Agency for Toxic Substances and Disease Registry (ATSDR), very little metallic mercury (less than 0.01%) is absorbed by the body, even if it is swallowed. However, if the same mercury is inhaled as a vapour, about 80% is absorbed into the bloodstream. About 95% of methyl mercury (the type found in fish and other seafood) is absorbed by the stomach and intestines. The most common source of human exposure to methyl mercury is as a result of eating contaminated seafood.  Fish that come from contaminated waters and larger predator fish – fish that have eaten smaller fish – may have significantly increased concentrations of methyl mercury.  This is why it is recommended that you know the source of the fish you consume and that you limit the quantity of large predator fish you eat.Once mercury is absorbed, it finds its way into a variety of body organs, including the kidney and brain. The body will slowly get rid of mercury through the urine and stool, but if excessive amounts are present, it can permanently damage the kidneys, nervous system, and brain. Pregnant women with elevated blood concentrations of mercury can pass it on to their foetus, affecting development especially the foetus’s brain, kidneys, and nerves.  Mercury can be passed from mother to baby through breast milk during nursing.


Test Name:
High-sensitivity cardiac-specific Troponins I and T


Why:
you have been diagnosed with HIV and are receiving anti-viral therapy that is not working effectively

When:
your HIV viral load values rise steadily even though you are receiving anti-viral therapy

Test General info:
In genotypic resistance testing, the genetic code of the particular strain of HIV a patient has is checked to see if there any genetic mutations that are known to cause drug resistance. HIV is said to be resistant to an antiviral medication if it keeps multiplying while a person is taking the drug. Changes (mutations) in the virus cause resistance. HIV mutates almost every time a new copy of the virus is made, but not every mutation causes resistance. Antiviral drugs control most types of HIV, however, a strain of virus containing a mutation that is resistant to a drug will multiply and become the most common form of the virus in the body (as all the other forms are destroyed by the drug). For certain drugs, single mutations of a gene increase resistance to high levels. For other drugs, there are several mutations that are associated with resistance. To avoid the development of antiviral drug resistance, it is usually recommended that you be treated with a combination of drugs that are from two different classes of antiretroviral drugs. This is known as highly active retroviral therapy or HAART.


Why:
monitor the status of HIV disease in conjunction with other lab tests and physical disease progression and to guide therapy.  Your viral load levels are usually used as an indicator of how well your immune system is dealing with HIV. If you are on anti-HI

When:
en first diagnosed with HIV, every 4 weeks at the start of therapy, and every 3-4 months during long-term therapy, or as your doctor recommends

Test General info:
This test measures the amount of HIV in your blood. This test detects and/or measures the amount (viral load) of RNA (nucleic acid) of the human immunodeficiency virus (HIV) in blood. It is the virus that causes acquired immunodeficiency syndrome (AIDS). When a person is infected with HIV, the virus replicates—it produces more and more copies of itself—and moves into the lymph nodes, spleen, and other parts of the body. In the early stages of infection there may not be any noticeable signs or symptoms of disease or only flu-like symptoms, although the virus is usually present in high amounts. Even when there are no symptoms the virus continues to replicate and to damage or kill immune cells. Eventually, the immune system is so weakened that the disease begins to affect the body’s ability to fight infections and certain cancers. More symptoms begin to appear at this stage as the body becomes more susceptible to infections with microorganisms such as tuberculosis and fungi or other diseases such as Kaposi’s sarcoma.

There is still concern that there is a lot of virus in other places in the body, not just the blood - only 2% of HIV is circulating in the blood, the rest is in the lymph system and other body tissue . Early results indicate that changes in viral load in the blood are mirrored in the lymph system, but research into this is continuing. ``Viral load`` means the number of HIV particles or copies of the virus present in the blood.

About 3-8 weeks (rarely up to six months) after exposure to the virus, the body begins to produce HIV antibodies in response to the infection. These antibodies can be detected with a screening test to determine if you have been infected with HIV. However, if your exposure occurred within the last few weeks, the level of antibody may not be high enough to be detected. It is in this “window period” of more recent exposure that the virus may be detectable with an HIV RNA test (viral load) to determine your HIV status. Because the level of technology and resources needed to perform this test are high, it is not as widely available as the antibody test and is used infrequently for diagnosis. 

As HIV progresses the virus continues to replicate and the number of copies of virus, the “viral load”, in the blood increases. If you have been diagnosed with HIV, the measurement of an HIV viral load (HIV RNA) gives your doctor a general indication of how much HIV is present in the body, and how rapidly the virus is replicating. The test can help determine, along with a CD4 count, if and when treatment should be initiated, when to test for drug resistance or if a different type of treatment protocol is needed. Treatment with anti-viral agents can decrease the viral load in the blood to low or undetectable levels, but cannot fully eradicate it from the body.


Related Tests:
Cardiac risk assessment; serum folate; serum vitamin B12

Why:
find out if you are at high risk of a heart attack or stroke; also used to determine if you are folate-deficient or vitamin B12-deficient as blood homocysteine concentration can be raised in both conditions

When:
you have had a heart attack or stroke, particularly in the absence of traditional risk factors or as part of a cardiac risk assessment

Test General info:
This test measures the level of homocysteine in the blood. Homocysteine is a sulphur-containing amino acid that is normally present in very small amounts in all cells of the body. Homocysteine is a product of methionine metabolism, and methionine is one of the eleven “essential” amino acids (an essential amino acids must be derived from the diet since the body cannot make them). In healthy cells, homocysteine is quickly converted to other products. 

Folic acid (folate) is one of the ``B`` vitamins that is needed to metabolise homocysteine. Vitamin B12, another B vitamin, helps keep folate in its active form, allowing it to keep homocysteine levels low.  People who are deficient in these vitamins may have increased levels of homocysteine.


Formal Name:
Oestrogen and Progesterone receptor status

Why:
determine whether a breast cancer tumour is positive for oestrogen and/or progesterone receptors, which helps to guide treatment and determine prognosis

When:
you have been diagnosed with breast cancer and your doctor wants to determine whether the tumour`s growth is influenced by the hormones oestrogen and/or progesterone

Sample Type:
sample of breast cancer tissue obtained during a biopsy or a tumour removed surgically during a lumpectomy or mastectomy

Test General info:
Oestrogen receptors and progesterone receptors are specialised proteins found within certain cells throughout the body. These receptors bind the female hormones, oestrogen and progesterone, which both circulate in the blood.

Many breast cancer tumours have receptors for oestrogen and/or progesterone, often in large numbers. When receptors are present, the tumour is said to be Oestrogen Receptor positive (ER-positive) and/or Progesterone Receptor positive (PR-positive). These tumours are said to be hormone-dependent, and oestrogen and/or progesterone feed their growth. Breast cancer tissue can be tested to see if it is positive for these receptors.


Test Name:
Human epidermal growth factor receptor-2


Test Name:
Human immunodeficiency virus antibody test


Related Tests:
Growth Hormone (GH), Glucose, Glucose Tolerance Test, GH Stimulation Test

Why:
identify diseases and conditions caused by deficiencies and overproduction of growth hormone (GH), to detect disease of the pituitary gland, and to monitor the effectiveness of growth hormone replacement treatment

When:
part of an evaluation of pituitary function;
1. when you are growing more slowly than normal, have short stature, have delayed development (in children) or decreased bone density, reduced muscle strength, and increased lipids (in adults), all of which suggest insufficient GH and IGF-1 production
2. when you have symptoms of gigantism (in children) or acromegaly (in adults) that suggest excess GH and IGF-1 production
3. during and after treatment for GH abnormalities

Test General info:
The insulin-like growth factor-1 (IGF-1) test is an indirect measure of the average amount of growth hormone (GH) being produced by the body. IGF-1 and GH are peptide hormones which are small proteins made up of a small chain of amino acids. IGF-1 and GH are vital for normal bone and tissue growth and development. GH is produced by the pituitary gland, a grape-sized gland which sits at base of the brain behind the bridge of your nose. GH is secreted into the bloodstream in pulses throughout the day and night with peaks that occur mostly during the night. IGF-1 is produced in response to GH stimulation and mainly comes from the liver with a little from muscles. It mediates many of the actions of GH, stimulating the growth of bones and other tissues and increasing the production of muscle mass. IGF-1 excesses and deficiencies mirrors those of GH , but its level does not fluctuate during the day as does GH which makes it a useful indicator of average GH levels.Like GH, IGF-1 levels are normally low in early childhood, increase gradually during childhood, peak during puberty, and then decline in adult life. Deficiencies in GH and IGF-1 may be caused by conditions such as hypopituitarism or by the presence of a non-GH-producing pituitary tumour that damages hormone-producing cells. Deficiencies in IGF-1 also occur where there is a lack of responsiveness to GH. This insensitivity may be primary (genetic) or secondary as a consequence of conditions such as  malnutrition and chronic diseases.Deficiencies early in life can inhibit bone growth and overall development and can result in a child with a shorter than normal stature. In adults, decreased production can lead to low bone densities, less muscle mass, and altered lipids.Excess GH and IGF-1 can cause abnormal growth of the skeleton and other signs and symptoms characteristic of gigantism and acromegaly. In children, gigantism causes bones to grow longer, resulting in a very tall person with large feet and hands. In adults, acromegaly causes bones to thicken and soft tissues, such as the nose, to swell. Both conditions can lead to enlarged organs, such as the heart, and to other complications such as type 2 diabetes, increased cardiovascular disease risk, high blood pressure, arthritis, and a decreased life span. The most common reason for the pituitary to secrete excessive amounts of GH is a GH-producing pituitary tumour (usually benign). Frequently, the tumour can be surgically removed and/or treated with drugs or radiation. In most cases, this will cause GH and IGF-1 levels to return to normal or near normal levels.


Other Names:
Serum Protein Electrophoresis (SPE), Urine Protein Electrophoresis (UPE), IFE

Formal Name:
Serum protein electrophoresis and urine protein electrophoresis

Why:
help diagnose and monitor tumours of the antibody producing cells (B lymphocytes) and to diagnose and monitor deficiencies of the immune system

When:
your doctor suspects that you have a condition that affects the antibody concentrations in the blood either by abnormal production or excessive loss

Sample Type:
blood sample taken from a vein in your arm; sometimes a random or 24-hour urine sample

Test General info:
Protein electrophoresis is a method for separating the proteins found in blood (serum) or urine. During the test, an electric current is used to move the proteins across a thin layer of agarose gel. The distances that individual proteins travel depend on their size, shape, and electrical charge. These separated proteins may be detected by the use of a dye that binds to (stains) all of the proteins and reveals a characteristic pattern of bands. Each band indicates the presence of a particular protein or group of proteins, while the size of the band is a rough indication of the quantity. This pattern of bands is converted into a visual graph, showing vertical spikes or peaks where there is a lot of protein and smaller peaks or valleys where there is less. A newer method called capillary zone electrophoresis (CZE) separates proteins by passing them through a long, thin column, producing a graph that is very similar to the one made by running the protein through an agarose gel.

Specific proteins of interest can be identified by separating the proteins by gel electrophoresis and then adding an antibody. The antibody can recognise individual proteins and sticks to them making a big complex that gets caught in the gel. All the other proteins in the system are washed away and the gel stained so the proteins in question can be identified. This procedure is called immunofixation electrophoresis (IFE). 

Serum proteins are separated into six major groupings by protein electrophoresis. These fractions are called albumin, alpha 1, alpha 2, beta 1, beta 2 and gamma. Albumin, which is produced in the liver, forms its own group and accounts for about 60% of the protein in the blood. `Globulins` is a collective term used to refer to proteins other than albumin. With the exception of the immunoglobulins and some complement proteins, most of the globulins are produced in the liver. These groups are described more fully in the table, Protein Groups.

The bands seen on protein electrophoresis form characteristic patterns. Alterations to these patterns are associated with a variety of different diseases and conditions. For example in multiple myeloma (a cancer of certain types of white blood cells called plasma cells), the uncontrolled growth and division of a malignant plasma cell leads to the production of large amounts of a single type of immunoglobulin (antibody). In contrast to other proteins in serum, which are typically of a single type, antibodies (immunoglobulins) must differ from each other to be able to recognise bacteria, viruses and other `foreign` substances. Each time the body is exposed to a virus, for example, one plasma cell replicates and makes a group (or clone) of plasma cells to produce antibody to eliminate it. Since our total immunoglobulin represents antibody made by many clones, we refer to it as a polyclonal pattern. When there is a cancer of plasma cells, only one type of antibody is produced, termed a monoclonal pattern. This abnormal protein can be seen as a characteristic band on the electrophoresis gel.


Other Names:
Immunophenotyping by Flow Cytometry or Immunohistochemistry

Related Tests:
FBC, White Blood Cell Differential Count, Blood Film, Bone Marrow Aspiration and Biopsy, CD4 and CD8

Why:
help diagnose and classify a leukaemia or lymphoma; to help guide treatment; to detect and evaluate residual cancer cells

When:
en a doctor thinks that you may have leukaemia or lymphoma; when you have been diagnosed with leukaemia or lymphoma, but the specific subtype is unknown; sometimes to evaluate the effectiveness of treatment or to evaluate for recurrent disease

Sample Type:
blood sample taken from a vein in your arm; sometimes a bone marrow, tissue, or fluid sample collected by your doctor

Test General info:
Immunophenotyping detects the presence or absence of white blood cell (WBC) antigens. These antigens are protein structures found on the surface or interior of WBCs. Typical groupings of antigens are present on normal WBCs. Atypical but characteristic groupings are seen with specific leukaemias and lymphomas. This allows immunophenotyping to be useful in helping to diagnose and classify these blood cell cancers.Leukaemias are caused by abnormal types of WBC termed lymphocytes or myeloid (granular) WBC that begin to clone themselves. This leads to monoclonal lymphocytic or myeloid Leukaemias. Lymphomas are caused by abnormal lymphocytes that become monoclonal and lead to cancer of the lymph system. The monoclonal cells produced do not fight infections like normal WBCs, and they do not die at a normal rate. They accumulate in the bone marrow or in the lymph node where they originated. As the number of WBC clones increases, they may crowd out and inhibit the production of normal red and white blood cells and the leukaemia or lymphoma cells may be released into the blood stream.Full blood count (FBC) and differential tests performed on a sample of blood from someone with leukaemia or lymphoma will usually reveal an increased number of white blood cells with a predominance of one type of WBC. These tests may suggest lymphoma or leukaemia, but more information is generally needed to confirm a diagnosis. FBC and differential testing often cannot confirm monoclonal WBCs or detect the subtle differences that may exist between different types of blood cell cancers and they cannot distinguish between the different types of lymphocytes or myeloid WBCs.With immunophenotyping, a blood, bone marrow, or other sample can be tested to gather this information – information that is then used to identify a specific type of leukaemia or lymphoma and, where possible, used to predict its likely aggressiveness and/or responsiveness to certain treatment. The identifications and predictions made are based upon a ``library`` of antigen associations and patterns that have been established over time.Most of the antigens that immunophenotyping detects are identified by a CD (clusters of differentiation or cluster designation) number, such as: CD1a, CD2, CD3, CD4, CD8, CD13, CD19, CD20, CD33, CD61, or CD235. CD numbers represent a naming convention that is based upon international consensus. Several hundred antigens have been identified and received CD designations, but only a small number of these are routinely tested for clinical use.Flow cytometry is the technique most used for Immunophenotyping . It is performed by processing a blood, bone marrow, tissue, or fluid sample and then adding specific antibodies that have been tagged with fluorescent markers. These antibodies attach to corresponding antigens on the white blood cells, when the antigens are present. The WBCs are then sent in a fluid stream past multiple lasers and detectors and each cell is analysed individually.The flow cytometer rapidly measures characteristics about each cell, such as its size and granularity, and evaluates the type and quantity of fluorescent antigen-antibody complexes that are present. Thousands of cells are evaluated during the test. Results are then graphed and compared to ``normal`` results and to patterns that are known to be associated with different leukaemias and lymphomas. This process allows the person interpreting the test results to determine the types of WBCs present, their maturity, and to determine the types and quantities of antigens on or in these cells.


Test Name:
Immunophenotyping by Flow Cytometry or Immunohistochemistry


Why:
screen for cystic fibrosis (CF) in newborn infants

When:
en a newborn infant has signs and symptoms of cystic fibrosis particularly when it passes no stools in the first 24 to 48 hours of life (meconium ileus) or where there is a high risk of the baby having the cystic fibrosis due to family history

Test General info:
Trypsin is produced from trypsinogen. Trypsinogen is normally produced in the pancreas and is carried to the small intestine where it changes from an inactive ‘proenzyme’ to the active ‘enzyme’ trypsin which is used to help the body digest proteins.  

In babies with cystic fibrosis, mucous can block the passage ways (ducts) from the pancreas into the small intestine. The mucos prevents trypsinogen from reaching the intestines resulting in a build-up of the protein in the blood. This can process can be detected and measured because ‘immunoreactive’ trypsin (IRT) levels increase in the blood of the infant. Infants with cystic fibrosis 1 to 2 weeks of age show increased levels of IRT in the plasma in the neonatal heal-prick test. It is currently the best screening test for cystic fibrosis but cannot be done after the first few weeks of life since it falls as the disease if the pancreas (pancreatictic insufficiency) develops. Several factors other than cystic fibrosis can affect the test result and therefore not all babies with high IRT will have cystic fibrosis. Where an elevated level is obtained, further investigation either by sweat testing or genetic analyses may be required.


Related Tests:
Calcium, Electrolytes, Vitamin D, Magnesium, Parathyroid Hormone (PTH)

Why:
evaluate the level of phosphate in your blood and to aid in the diagnosis of conditions known to cause abnormally high or low levels

When:
a follow-up to an abnormal calcium level, if you have a kidney disorder or uncontrolled diabetes, and if you are taking calcium or phosphate supplements

Test General info:
The serum phosphate test measures the amount of inorganic phosphate in your blood plasma (the liquid part of blood).

In the body, phosphorus is combined with oxygen to form a variety of phosphates (PO4). Phosphates are vital for energy production, muscle and nerve function, and bone growth. They also play an important role as a buffer, helping to maintain the body’s acid-base balance. About 70% to 80% of the phosphates are combined with calcium to help form bones and teeth, about 10% are found in muscle, and about 1% is in nerve tissue. The rest is found within cells throughout the body, where it is mainly used to store energy; about 1% of total body phosphate is found within plasma. 

Most phosphate in the body comes from dietary sources. A variety of foods, such as beans, peas and nuts, cereals, dairy products, eggs, beef, chicken, and fish contain significant amounts of phosphate. The body maintains phosphate levels in the blood by regulating how much it absorbs from the intestines and how much it excretes or conserves in the kidneys.


Related Tests:
International Normalised Ratio (INR), Activated Clotting Time (ACT), Activated Partial Thromboplastin Time (aPTT or PTT), Kaolin Cephalin Clotting Time (KCCT), Fibrinogen, Coagulation Factors

Why:
help diagnose a bleeding disorder; to help estimate the severity of liver disease. A tightly controlled version of the PT called the International Normalised Ratio (INR) is used to measure the effect of anticoagulant drugs such as warfarin.

When:
test preparation is needed. If the patient is receiving anticoagulant therapy, the specimen should be collected before the daily dose is taken. It is essential the blood is taken quickly and smoothly and that the anticoagulant bottle is filled exactly to the designated mark or the result may be inaccurate.

Test General info:
The test measures how long it takes for your blood to begin to form clots. Prothrombin is a plasma protein produced by the liver. Clotting is caused by a series of clotting factors which activate each other, including the conversion of prothrombin to thrombin. The test used to measure the activity of this clotting factor is called the prothrombin time, or PT.


Related Tests:
C-Peptide, Glucose, Glucose Tolerance Test (GTT)

Why:
help determine the cause of low blood glucose (hypoglycaemia), diagnose an insulinoma (insulin-producing tumour), and to help evaluate insulin production.

When:
you have hypoglycaemia, if you have symptoms suggesting insulin is being inappropriately produced by your body, and rarely if you have diabetes and your doctor wants to monitor your insulin production

Test General info:
Insulin is a protein hormone that is produced and stored in the beta cells of the pancreas. It is initially made as a larger molecule, preproinsulin, that is cleaved twice to form the smaller insulin hormone prior to release and inactive fragments proinsulin and C-peptide.When blood glucose levels rise after a meal, insulin causes glucose to be taken up by the body`s cells, especially muscle, liver and fat cells, where is it is used for energy production and storage. Insulin is required to regulate blood glucose concentrations and plays a role in controlling the levels of carbohydrates and fats stored in the body.Humans need insulin on a daily basis to survive. Without insulin, glucose cannot reach most of the body`s cells. Without glucose, the cells starve, and blood glucose levels rise to dangerous levels. Eventually, very high glucose concentrations lead to a life-threatening condition called a diabetic coma.Insulin and glucose levels must be in balance. Too much insulin in the blood, for the blood glucose level, is known as `hyperinsulinaemia`. This is seen with insulinomas (insulin-producing tumours usually found within the pancreas) or, more commonly, with an excess amount of injected insulin or other diabetic drugs stimulating insulin release. Hyperinsulinaemia causes hypoglycaemia (low blood glucose levels), which can lead to sweating, rapid heart beat, hunger, confusion, visual problems, and seizures. Since the brain is totally dependent on blood glucose as an energy source, lack of glucose due to hyperinsulinaemia can lead fairly quickly to confusion, coma, brain damage and/or death.Insulin also signals to the body that there is ‘fuel’ available. When no ‘fuel’ is available (in the form of glucose) and there is no insulin the body uses fats to make ketones which are the only other fuel the brain can use. In hyperinsulinaemia the body is unable to respond to the low glucose by making ketones and so the brain suffers. Therefore if ketones can be detected in the blood, in someone with a low glucose, an insulin test is no longer needed as it must be absent.


Related Tests:
Calcium; Phosphate; Magnesium; Vitamin D

Why:
determine whether PTH concentrations are responding normally to changes in blood calcium concentration; to distinguish the cause of calcium imbalances, and to evaluate parathyroid function. In some laboratories, PTH may be measured during surgery for hype

When:
en calcium blood levels are higher or lower than normal, and when your doctor wants to determine how well your parathyroid gland is functioning.

Test General info:
Parathyroid hormone (PTH) helps the body maintain stable amounts of calcium in the bloodstream. It is part of a ‘feedback loop’ that includes calcium, PTH, vitamin D, and to some extent phosphate and magnesium. Conditions and diseases that disrupt this feedback loop can cause inappropriate elevations or decreases in calcium and PTH and lead to symptoms of hypercalcaemia (raised blood concentrations of calcium) or hypocalcaemia (low blood concentrations of calcium).PTH is produced by four parathyroid glands that are located in the neck beside the thyroid gland. Normally, these glands secrete PTH into the bloodstream in response to low blood calcium concentration. Parathyroid hormone then works in three ways to help raise blood calcium back to normal. It takes calcium from the body’s bone, stimulates the activation of vitamin D in the kidney (which in turn increases the absorption of calcium from the intestines), and suppresses the excretion of calcium in the urine (while encouraging excretion of phosphate). As blood calcium concentrations begin to rise, the concentration of PTH will normally decrease. Parathyroid hormone itself is composed of 84 amino acids (sometimes called PTH (1-84)). Once it is released from the parathyroid gland into the blood stream, it has a very short life-span; levels fall by half in less than 5 minutes. The fall is caused primarily by the breakdown of PTH to smaller fragments.


Related Tests:
Immunoreactive trypsin (IRT); CF gene mutation

When:
en a newborn or infant has symptoms that suggest cystic fibrosis, such as frequent respiratory infections and chronic cough, persistent diarrhoea, foul-smelling bulky greasy stools, and malnutrition; and as a follow-up, confirmatory test to help diagnose CF

Test General info:
Sodium and chloride are part of your body’s electrolyte balance. They help regulate the fluid balance in your blood and tissues. Normally, chloride travels in and out of the body’s cells, helping to maintain electrical neutrality and water balance. Chloride’s level usually mirrors that of sodium. 

When a patient has cystic fibrosis (CF), they have inherited an abnormal (mutated) pair of genes on chromosome number 7. These genes normally produce a protein (cystic fibrosis transmembrane conductance regulator (CFTR)) that lets chloride out of cells and into the surrounding fluid. When a mutation is present, the CFTR protein may not work properly or may be totally absent. Since CFTR levels are usually highest in the cells lining the internal surfaces of the pancreas, sweat glands, salivary glands, intestine, and reproductive organs, these are the areas most affected by CF. 

The cells absorb more water than normal, making liquid produced by the cells thick and sticky and the sweat about five times saltier than normal. This increase of salt in the sweat can be measured, and is called the sweat chloride test.


Related Tests:
Gram stain; White blood cell count (WBC); Red blood cell count (RBC); C reactive protein (CRP); erythrocyte sedimentation rate (ESR); blood culture

Why:
help diagnose the cause of joint inflammation, pain, and/or swelling

When:
en one or more of your joints are swollen, red, and/or painful

Sample Type:
synovial fluid sample is obtained by inserting a needle into the space between the bones at a joint

Test General info:
Synovial fluid is a thick liquid that acts as a lubricant for the major joints of the body. It is found in small quantities in the spaces between the joints. Here the fluid is produced and contained by the synovial membranes which cover the surfaces of the bones. Synovial fluid cushions the bone ends and reduces friction during joint movement in the knees, shoulders, hips, hands, and feet.Synovial fluid analysis consists of inspection of fluid, as well as tests that detect changes in synovial fluid that may indicate the presence of diseases that affect joint structure and function.


Why:
diagnose levels of potassium that are too high (hyperkalaemia) or too low (hypokalaemia)

When:
part of a routine medical examination or to investigate a serious illness, such as high blood pressure or kidney disease

Test General info:
Potassium is present in all body fluids, but most potassium is within your cells, with only a very small amount in the serum or plasma component of the blood. If potassium goes too low or too high, your health may be impaired. An abnormal concentration can alter the function of the nerves and muscles; for example, in extreme cases you may experience heart rhythm disturbances or the heart muscle may even lose its ability to contract.


Related Tests:
Valproic Acid, Carbamazepine, Phenytoin, Therapeutic Drug Monitoring

Why:
some cases, to determine the concentration of levetiracetam in the blood to establish an individualised dose; to detect toxicity or verify that a person is taking the medication as prescribed (compliance); to monitor changes that may affect drug clearance

When:
some cases, at the start of treatment when establishing dosage; when indicated to detect low or excessive (potentially toxic) concentrations; when a person has decreased kidney function; occasionally to verify compliance

Test General info:
Levetiracetam is a drug that is used to treat certain seizure disorders (also called epilepsy). It is prescribed as an adjunctive (secondary) treatment in combination with other antiepileptic drugs. This test measures the amount of levetiracetam in the blood.Epilepsy affects the brain`s ability to transmit electrical impulses and to regulate nerve activity. During a seizure, a person may experience changes in consciousness, alterations in sight, smell, and taste, and may experience convulsions. The frequency of seizures varies from a single episode, to occasional seizures, to recurrent seizures. Seizures are categorised by the parts of the brain and body that are affected. Levetiracetam is prescribed to help prevent specific types of recurrent seizures.Levetiracetam is one of several newer second-generation antiepileptic drugs. It has a wider therapeutic range than many existing first-generation seizure medications. That is, the range of concentration in the blood in which the drug is effective without being toxic is broader, making it somewhat safer. It is also associated with fewer severe side effects and does not interact with as many other drugs. Since it is relatively new, however, it has less of a ‘use history’ – its long-term safety and efficacy and its appropriate therapeutic range are less well established.Because levetiracetam has a wider therapeutic range, it does not need to be monitored in the same manner as first-generation antiepileptic drugs. (For further discussion of this, see the article on Therapeutic Drug Monitoring.) However, there are circumstances in which it is useful and sometimes necessary to measure blood levels. Some of these include:To establish the range that is therapeutic for an individual; after treatment has started and the individual has relief from symptoms (no seizures) and suffers no side effects, the concentration of the drug in the blood is determined. The range around this value is considered therapeutic for the person and may be used to evaluate their treatment in the future if their health status or other factors change. To verify that a person`s symptoms (seizures or side effects) are not due to too little or too much drug; to verify that a person is taking the medication as prescribed To evaluate and adjust the dose as necessary in certain conditions such as: Kidney disease—levetiracetam is cleared from the body by the kidneys, so anything that affects kidney function can affect blood levels of the drug. A change or addition of other drugs Aging—people typically are prescribed seizure medications for life and, as they age, the amount of drug needed to be effective may change. Pregnancy—this condition can temporarily affect drug metabolism and clearance.At the start of therapy, doses of levetiracetam may be gradually increased until a standard amount is reached. Once a stable dose is achieved, a blood level may sometimes be measured to ensure that it is within the therapeutic range. Since levetiracetam is an adjunct (secondary) medication, the doctor will consider the effectiveness of both drugs that are prescribed and adjust them as necessary.


Related Tests:
Activated Partial Thromboplastin Time (aPTT), LA Sensitive aPTT (LA-aPTT), Thrombin Time, Autoimmune Diseases, Dilute or Modified Russell Viper Venom Time (dRVVT or MRVVT), Anticardiolipin Antibodies, Antiphospholipid Antibodies, Prothrombin Time (PT)

Why:
help evaluate a prolonged activated partial thromboplastin time (aPTT) and/or a thrombotic episode, to help determine the cause of recurrent fetal loss, as part of an evaluation for antiphospholipid syndrome. Not a diagnostic test for lupus (SLE).

When:
en you have a prolonged aPTT test. When you have had a venous or arterial thromboembolism. When you have had recurrent miscarriages, especially in the 2nd and 3rd trimesters.

Sample Type:
blood sample is obtained by inserting a needle into a vein in the arm.

Test General info:
Lupus anticoagulant is a protein that increases the risk of developing blood clots in both the veins and arteries. These clots may block blood flow in any part of the body, leading to strokes, heart attacks, pulmonary embolisms, deep vein thrombosis, and to recurrent foetal loss, especially in the 2nd and 3rd trimesters (thought to be related to clotting in placental blood vessels). The lupus anticoagulant is an acquired, not inherited, condition. Although it is found most frequently in those with autoimmune diseases, such as Systemic Lupus Erythematosus (SLE) and HIV, the lupus anticoagulant may also be seen chronically or temporarily in those with infections or cancers and in those who are taking certain medications, such as phenothiazines, chlorpromazine, procainamide, and fansidar. It is thought to be present in about 1 – 2% of the general population, and may develop in people with no known risk factors.
The term lupus anticoagulant (LA) is misleading. It is not a diagnostic test for lupus but gets its name because it was first discovered in patients with SLE, and because it often prolongs the activated partial thromboplastin time (aPTT) test - a timed blood test usually associated with anticoagulation and bleeding, not with thrombosis. It prolongs the aPTT test, as well as several other related tests, because the lupus anticoagulant binds to phospholipids and the reagents (chemicals) used in performing the aPTT test contain phospholipids.In the body phospholipids play a vital role in the blood clotting process. They are found primarily on the surface of platelets and cell membranes and assist in the activation of several coagulation factors- proteins that are sequentially activated in response to blood vessel or tissue damage in a process called the coagulation cascade. The lupus anticoagulant is one of three types of test for antiphospholipid syndrome, associated with an increased risk of thrombosis. The others are anticardiolipin antibodies and antibodies against beta-2 glycoprotein 1 (less common). Any or all may be positive in antiphospholipid syndrome (also called Hughes` syndrome). Each interferes with the clotting process in a fashion that is not well understood and, singly or together, they increase a person`s tendency to clot.While anticardiolipin and anti-beta2-glycoprotein I antibodies may be tested for directly, there is not a single test for the lupus anticoagulant. It is usually diagnosed by using a panel of sequential tests that are taken through different stages. These tests operate on the principle that the lupus anticoagulant is a non-specific inhibitor – it does not target a specific coagulation factor, it binds to the assay’s phospholipids, inhibiting and prolonging the tests. The first test is usually an aPTT (or an LA-aPTT, a version of the test made more sensitive to LA) and the first stage is to see whether the original test is prolonged. If it is, then the patient’s plasma is mixed with pooled normal plasma (a combination of blood from different donors that contains all of the coagulation factors). If the prolongation is due to a specific coagulation factor deficiency then the normal plasma should ``correct`` the test to normal. If it is due to a non-specific inhibitor it will still be prolonged. In the third stage, additional phospholipids are added to the test. This should be sufficient to correct the test to near normal levels if the lupus anticoagulant is the cause of the abnormality. The Dilute Russell Viper Venom Test is a sensitive aPTT-like test for LA, and can also be performed with a phospholipid correction step.


Why:
help detect hypoxia and other diseases that cause excess production or reduced removal of lactate from the blood

When:
you have symptoms such as rapid breathing, sickness, and sweating that suggest a lack of oxygen or an acid/base imbalance; if your doctor suspects that you may have an inherited metabolic or mitochondrial disorder

Sample Type:
blood sample taken from a vein in your arm; sometimes a blood sample collected from an artery and, rarely, a sample of cerebrospinal fluid collected from the spine

Test General info:
This test measures the amount of lactate in the blood or, more rarely, in the cerebrospinal fluid. Lactate is the ionic (electrically charged) form of lactic acid. It is produced by muscle cells, red blood cells, brain, and other tissues during anaerobic (oxygen deficient) energy production and is usually present at low concentrations in the blood. Aerobic energy production is the body’s preferred process, but it requires an adequate supply of oxygen. Aerobic energy production occurs in the mitochondria, tiny power stations inside each cell of the body that use glucose and oxygen to produce ATP (adenosine triphosphate) which is the body’s main source of energy.When cellular oxygen levels are low, or the mitochondria are not working properly, the body must turn to less efficient anaerobic energy production to metabolise glucose and produce ATP. In this process, the primary by-product is lactic acid, which can build up faster than the liver can break it down. When lactic acid levels increase a lot in the blood, the affected person is said to have first hyperlactataemia and then lactic acidosis (LA). The body can often compensate for the effects of hyperlactataemia, but lactic acidosis can be severe enough to disrupt a person’s acid/base (pH) balance and cause symptoms such as muscular weakness, rapid breathing, feeling sick, vomiting, sweating, and even coma.

Lactic acidosis is separated into two types: A and B. Type A is more common and may be due to inadequate oxygen uptake in the lungs and/or to decreased blood flow (hypoperfusion) resulting in decreased transport of oxygen to the tissues. The most common reason for this is shock from a variety of causes including trauma and blood loss, but LA may also be due to conditions such as heart attack, congestive heart failure, and pulmonary oedema (fluid in the lungs). Type B is caused by conditions that increase the amount of lactate/lactic acid in the blood but are not related to a decreased availability of oxygen. This includes liver and kidney disease, diabetes, leukaemia, AIDS, glycogen storage diseases (such as glucose-6-phosphatase deficiency), drugs and toxins, severe infections (both systemic sepsis and meningitis), and a variety of inherited metabolic and mitochondrial diseases (forms of muscular dystrophy that affect normal ATP production). Strenuous exercise can also result in increased blood lactate concentrations.


Other Names:
LD; Lactate dehydrogenase; Total LDH; LDH isoenzymes

Related Tests:
CK (Creatine Kinase), CK-MB, Troponin, Myoglobin

Why:
help identify the cause and location of tissue damage in the body, and to monitor its progress. LDH is elevated in a wide variety of conditions reflecting its wide spread tissue distribution. Historically, has been used to help diagnose and monitor a hear

When:
ong with other tests, when your doctor suspects that you have an acute or chronic condition that is causing tissue or cellular destruction and wants to identify and monitor the problem.

Test General info:
Lactate dehydrogenase (LDH, or LD) is an enzyme found in almost all body tissues. Usually the concentration in the blood is low, because  it usually stays contained within the tissues’ cells. When cells are damaged or destroyed, however, they release LDH into the bloodstream, causing blood levels to rise. For this reason, LDH is used as a general marker of injury to cells; it is not useful for determining which specific cells are damaged.Elevations of LDH may be measured either as a total LDH or as LDH isoenzymes. Isoenzymes are slightly different molecular versions of the same enzyme. A total LDH level is an overall measurement of five different LDH isoenzymes. A high total LDH level reflects tissue damage but it is not specific to any one type of tissue, and so, by itself, it cannot be used to identify the underlying cause or its location.Although there is some overlap, each of the five LDH isoenzymes tends to be concentrated in specific body tissues. Because of this, measurements of the individual LDH isoenzyme levels can be used, along with other tests, to help determine the disease or condition causing cellular damage and to help identify the organs and tissues involved. In general, the isoenzyme locations tend to be:LDH-1 - heart, red cells, kidney, germ cellsLDH-2 - heart, red blood cells, kidney (lesser amounts than LDH-1)LDH-3 - lungs and other tissuesLDH-4 - white blood cells, lymph nodes; muscle, liver (smaller amounts than LDH-5)LDH-5 - liver, muscleWhile all of the isoenzymes are represented in the total LDH, LDH-2 usually makes up the greatest percentage.


SI:
> 0.83  increase in plasma glucose level


Other Names:
PPD (Purified Protein Derivative); Mantoux (previously Heaf test); Latent Tuberculosis Infection test (LTI)

Why:
help determine whether or not you may have been exposed to and become infected by the Mycobacterium tuberculosis (TB) bacteria

When:
en you have diseases or conditions that weaken your immune system and put you at a greater risk of developing active tuberculosis. When you have had close contact with someone who has active TB, or work or live in a high risk environment. When you have lived for a period of time in a foreign country where TB may be more common. Sometimes as part of an examination prior to starting a new job (such as a healthcare worker).

Sample Type:
sample is required. A small amount of purified protein derivative (PPD) solution is injected just under the first layer of skin of your inner forearm.

Test General info:
Tuberculosis (TB) is an infectious disease caused by a bacterium named Mycobacterium tuberculosis. It may affect many body organs, but primarily affects the lungs (pulmonary). Tuberculosis, (once called consumption), has been causing death for thousands of years.TB may cause a latent or inactive infection or an active, progressive disease. About 90% of the people who become infected with TB manage to control its growth and confine the TB to a few cells in the body. The bacteria in these cells are inactive but still alive. The patient is not sick, they do not have any symptoms, and they are not infectious, but they do have a ``latent TB infection.`` If the patient`s immune status is later compromised, the latent TB bacteria may begin to grow again, leading to an active case of tuberculosis disease. This active TB does cause illness in the patient and it can be passed to others through respiratory secretions such as sputum (spit or phlegm) or aerosols released by coughing, sneezing, laughing, or breathing. If the test is positive, further testing will be done to look for signs of active tuberculosis.


Why:
your doctor thinks that you might have an infection, inflammatory illness, immune deficiency, bone marrow disease or allergy and; to monitor treatment

Sample Type:
blood sample taken from a vein in your arm or from a finger-prick or in babies a heelprick

Test General info:
The white blood cell (WBC) count indicates the number of white blood cells in a sample of blood. This count provides a clue to the presence of illness. White blood cells are made in the bone marrow and protect the body against infection and aid in the immune response. If an infection develops, white blood cells attack and destroy the micro-organism causing the infection.


Test Name:
LFTs, Liver panel, Hepatic function tests

Other Names:
LFTs, Liver panel, Hepatic function tests

Related Tests:
ALT, ALP, AST, Bilirubin, Albumin, Total Protein, GGT, Prothrombin Time (PT), Hepatitis A, Hepatitis B, Hepatitis C, Emergency and Overdose Drug Testing, Ethanol, ANA, SMA, Drugs of Abuse Testing, Copper, Caeruloplasmin

When:
en you have symptoms of a liver disorder such as jaundice or have been exposed to substances that can cause liver damage such as a paracetamol overdose

Test General info:
The liver is a large organ located in the upper right-hand part of the abdomen behind the lower ribs. It takes up drugs and toxic substances from the blood and renders them harmless. It produces proteins, including enzymes and blood clotting factors, helps maintain hormone balance and stores vitamins. The liver produces bile, a fluid that is transported through ducts to the gallbladder to be stored and then to the small intestine to help digest fats. 

Liver disease is detected, evaluated and monitored by combinations of up to five tests measured at the same time on a blood sample. These may include:

Alanine aminotransferase (ALT) – an enzyme mainly found in the liver; the best test for detecting hepatitisAspartate aminotransferase (AST) – an enzyme found in the liver and a few other places, particularly the heart and other muscles in the bodyTotal bilirubin – measures all the yellow bilirubin pigment in the bloodAnother test, conjugated bilirubin, measures the form made only in the liver and is often requested with total bilirubin in infants with jaundiceAlkaline phosphatase (ALP) – an enzyme related to the bile ducts; often increased when they are blocked, either inside or outside the liverAlbumin – measures the main protein made by the liver and tells how well the liver is making this proteinTotal protein - measures albumin and all other proteins in blood, including antibodies made to help fight off infectionsOther tests that can help to assess liver function include gamma-glutamyl transferase (GGT), 5’-nucleotidase (5’-NT) and prothrombin time (PT), together with bilirubin and urobilinogen in urine.


When:
you are having difficulty getting pregnant or are having irregular menstrual periods or when your doctor suspects that a child has delayed or earlier than expected sexual maturation.

Test General info:
Luteinising hormone (LH) is produced by the pituitary gland in the brain. Control of LH production is a complex system involving hormones produced by the gonads (ovaries or testes), the pituitary gland, and the hypothalamus, such as gonadotrophin-releasing hormone (GnRH). 

Women’s menstrual cycles are divided into 2 phases, the follicular and luteal, by a mid-cycle surge of follicle-stimulating hormone (FSH) and LH. The high level of LH (and FSH) at mid-cycle triggers ovulation (release of the egg from the ovary). LH also stimulates the ovaries to produce other hormones, mainly oestradiol. Oestradiol helps the pituitary gland to control the production of LH. At the time of the menopause, the ovaries stop functioning and LH levels rise. 

In men, LH stimulates the Leydig cells in the testes to produce testosterone. LH levels are relatively constant in men after puberty.

In infants and children, LH levels rise shortly after birth and then fall to very low levels (by 6 months in boys and 1-2 years in girls). At about 6-8 years, levels again rise with the beginning of puberty and the development of secondary sexual characteristics such as pubic hair, deepening voice in males and pubic hair and breast development in girls.


Why:
diagnose and monitor pancreatitis or other pancreatic disease

When:
en you have symptoms of a pancreatic disease, such as severe abdominal pain, fever, loss of appetite or nausea

Test General info:
Lipase is an enzyme manufactured primarily by the pancreas. It is released into the duodenum to help digest fatty foods. Small amounts are present in blood. When pancreatic cells are inflamed as in pancreatitis or when its path into the duodenum is blocked by a gallstone or, rarely, a pancreatic tumour, increased amounts of lipase pass into the blood.


Related Tests:
Cholesterol, HDL Cholesterol, Non-HDL cholesterol; LDL Cholesterol, Triglycerides, Apo A-I, Apo B, Lp(a)

Why:
assess your risk of developing cardiovascular disease (heart disease, stroke and related diseases); to monitor treatment

When:
ed 40 as part of a routine cardiovascular health check, or if you are already thought to be at risk of cardiovascular disease for another reason, or if you are taking (or are about to start) lipid-modifying treatments (e.g. statins).

Sample Type:
blood sample is obtained by inserting a needle into a vein in your arm, or occasionally from a fingerprick.

Test General info:
Lipids are a group of fats and fat-like substances that are important constituents of cells and sources of energy. They are necessary for life, but if present in excess they can lead to health problems – in particular cardiovascular disease. A lipid profile measures the level of specific lipids in the blood.Two types of lipids, cholesterol and triglycerides, are transported in the blood by particles called “lipoproteins”. Each particle contains a combination of protein, cholesterol, triglyceride, and phospholipid molecules. Lipoprotein particles are classified according to their density into high-density lipoproteins (HDL), intermediate-density lipoproteins (IDL), low-density lipoproteins (LDL), and very low-density lipoproteins (VLDL). Not all of these are measured as part of a routine lipid profile.A lipid profile typically includes:Total cholesterol —this test measures all of the cholesterol in all the lipoprotein particles.High-density lipoprotein cholesterol (HDL-C) — measures the cholesterol in HDL particles; often called ``good cholesterol`` because it removes excess cholesterol and carries it to the liver for removal.Non-HDL cholesterol (non-HDL-C) - calculated simply as ``total cholesterol minus HDL-C``. This is what is often referred to as ``bad cholesterol``, as unlike ``good`` HDL-C, it is carried away from the liver and into the walls of blood vessels. Here, it is deposited and begins to form ``plaques``, which can eventually lead to blockages. Non-HDL-C includes cholesterol carried by LDL, IDL, VLDL, and some also some other particles such as Lp(a) and lipoprotein remnants.Triglycerides — measures all the triglycerides in all the lipoprotein particles; most is in the very low-density lipoproteins (VLDL).Some other information may be reported as part of the lipid profile. These parameters are calculated from the results of the tests identified above.Cholesterol: HDL ratio — calculated ratio of total cholesterol to HDL-C.Low-density lipoprotein cholesterol (LDL-C) — calculates the cholesterol in LDL particles. LDL-C is a form of ``bad cholesterol`` - but not all bad cholesterol is LDL-C.


Related Tests:
Lipid Profile; Homocysteine; hs-CRP; Apo A; Apo B

Why:
part of a targeted screen for cardiovascular disease (coronary artery disease (CAD) and cerebrovascular disease). Lp(a) measurement may give additional information about the risk of developing cardiovascular disease in some people

When:
ur doctor may request Lp(a) measurement if you have a family history of premature cardiovascular disease or elevated Lp(a) or if you develop cardiovascular disease at a young age, particularly in the absence of conventional risk factors

Test General info:
Lp(a) is a risk factor for heart disease especially when LDL cholesterol is also raised. Lp(a) is a lipoprotein comprising a lipid rich core surrounded by an apolipoprotein (ApoB-100) and an apolipoprotein (a) molecule. In the body, apolipoprotein (a) can interfere with the function of plasminogen, which can result in blood clot formation and help LDL molecules bind to artery walls. This accelerates the development of plaques within the wall, which can then narrow and harden the artery. This dual action may explain the role of Lp(a) in the promotion of cardiovascular disease (CVD). 

The size of the Lp(a) molecule is consistent for one person but it varies across the human population. Lp(a) size varies because its apolipoprotein (a) has a genetically determined, varying number of units (called kringles) in it. As the number of kringles rises, so does the size of the Lp(a) molecule. In people of European ancestry, larger forms of Lp(a) are associated with lower blood concentrations, while smaller forms are associated with a higher concentration. There is evidence that the smaller forms of Lp(a) are more atherogenic (promotes plaque formation and narrowing of the artery) than the larger ones. Most analytical methods only measure the concentration of Lp(a) and give no indication of molecular size.

Lp(a) concentrations within the blood are genetically determined and will remain fairly constant in an individual over a lifetime. Concentration is not affected by diet, exercise, and other lifestyle modifications used to lower lipids within the blood. Lp(a) concentrations  are slightly lower in men than in women and increase slightly in women after the menopause. The concentration of Lp(a) also varies with ethnicity: patients of African American descent can have concentrations up to 4 times higher than Caucasians, but they may not have a higher risk for CAD.


Other Names:
Often referred to by brand name (Priadel, Camcolit, Liskonum, Li-Liquid)

Related Tests:
Therapeutic drug monitoring; Urea; Creatinine; TSH; T4

Why:
determine lithium concentration in the blood in order to maintain an appropriate level or to detect lithium toxicity

When:
regular intervals to monitor lithium levels; as needed to detect low or toxic concentrations

Test General info:
This test measures the amount of lithium in the blood. Lithium is a drug that is used to treat bipolar disorder. Bipolar disorder is a mental condition that is characterized by cycles of depression and mania. These cycles may be as short as a few days or weeks or may be months or years long. During a depressive episode, those affected may feel sad, hopeless, worthless, and lose interest in daily activities. They may be tired but have trouble sleeping, experience weight loss or gain, have difficulty concentrating, and have thoughts of suicide. During a manic episode, those affected may be euphoric, irritable, have high energy and grandiose ideas, use poor judgment, and participate in risky behaviour. Sometimes affected patients will have mixed episodes with aspects of both mania and depression. Bipolar disorder can affect both adults and children.  Lithium is prescribed to even out the moods of the person with bipolar disorder and is sometimes prescribed for patients with depression who are not responding well to other medications. It may take several weeks to months for lithium to affect a person’s mood. Dosages of the drug are adjusted until a steady concentration in the blood is reached. The actual amount of drug that it will take to reach this steady state will vary from person to person and may be affected by the individual’s age, general state of health, and other medications. Lithium levels must be maintained within a narrow therapeutic range. Too little lithium and the medication will not be effective; too much and patients will experience symptoms of lithium toxicity, such as nausea, vomiting, diarrhoea, confusion, and tremors. Extremely high levels can lead to loss of consciousness and/or seizures, and can be fatal.


Related Tests:
Calcium, Potassium, Phosphate, Parathyroid Hormone (PTH), Vitamin D

Why:
evaluate the concentration of magnesium in your blood and to help determine the cause of abnormal calcium and/or potassium levels

When:
you have symptoms (such as weakness, irritability, cardiac arrhythmia, nausea, and/or diarrhoea) that may be due to too much or too little magnesium or if you have abnormal calcium or potassium levels

Test General info:
This test measures the amount of magnesium in your blood. Normally, only a very small amount (about 1%) of the total magnesium found in the body is present in the blood. 

Magnesium is a mineral that is found in every cell of your body. It is vital to energy production, muscle contraction, nerve function, and maintenance of strong bones. About half of the body’s magnesium is combined with calcium and phosphorus to form bone. 

A wide variety of foods contain small amounts of magnesium, especially green vegetables such as spinach, and most magnesium in the body comes from dietary sources. The body maintains magnesium levels in its blood, cells, and bone by regulating how much it absorbs from the intestines and by how much it excretes or conserves in the kidneys.


Formal Name:
Urine metadrenalines (total and fractionated)

When:
en you have symptoms of increased catecholamines release, such as persistent or episodic high blood pressure, severe headaches, rapid heart rate, and sweating

Test General info:
This test measures the amounts of metadrenaline and normetadrenaline that are excreted in the urine over a 24-hour period. Metadrenaline and normetadrenaline are the inactive metabolites of the catecholamines adrenaline (epinephrine) and noradrenaline (norepinephrine). Catecholamines are a group of similar hormones produced in the adrenal medulla (central portion) of the adrenal glands. The adrenal gland is a small, triangular organ located on top of each kidney. The primary catecholamines are dopamine, adrenaline, and noradrenaline. These hormones are released into the bloodstream in response to physical or emotional stress. They help transmit nerve impulses in the brain, increase glucose and fatty acid release for energy, dilate small air passages in the lungs called bronchioles, and dilate the pupils. Noradrenaline also constricts blood vessels, which increases blood pressure, and adrenaline increases heart rate and metabolism. After completing their actions, the catecholamines are metabolised to form inactive compounds. Dopamine becomes 3-methoxytyramine (3-MT) and homovanillic acid (HVA), noradrenaline breaks down into normetadrenaline and vanillylmandelic acid (VMA) (also known as HMMA), and adrenaline becomes metadrenaline and VMA. Both the hormones and their metabolites are excreted in the urine.Urine metadrenaline testing measures the amount of both metadrenaline and normetadrenaline. These metabolites are usually present in the urine in small fluctuating amounts, that increase significantly during and shortly after the body is exposed to stress. Rare phaeochromocytomas and other neuroendocrine tumours, however, can produce large amounts of catecholamines, resulting in greatly increased concentrations of the hormones and their metabolites in both the blood and urine. The catecholamines that a phaeochromocytoma produces can cause persistent hypertension (high blood pressure) and episodes of severe hypertension. Phaeochromocytomas are responsible for high blood pressure in a very small proportion of individuals (approximately 0.1-0.6%). Other symptoms of catecholamine release include headaches, palpitations, sweating, nausea, anxiety, and tingling in the extremities.About 80-85% of paheochromocytomas are located in the adrenal glands. While a few are cancerous, most are benign – they do not spread beyond their original location – although most do continue to grow. Left untreated, the symptoms may worsen as the tumour grows and, over a period of time, the hypertension from a phaeochromocytoma may cause kidney damage, heart disease, and raise the risk of a stroke or heart attack.The urine metadrenaline test can be used to help detect the presence of phaeochromocytomas. It is important to diagnose and treat these rare tumours because they cause a potentially curable form of hypertension. In most cases, the tumours can be surgically removed and/or treated to significantly reduce the amount of catecholamines being produced and to reduce or eliminate associated symptoms and complications.


Why:
help detect early and/or mild vitamin B12 deficiency, especially at the tissue level; to help diagnose methylmalonic acidaemia, a rare inherited metabolic disorder

When:
you have a vitamin B12 concentration in the low end of the normal range and/or have symptoms of neuropathy, such as numbness and tingling in the hands and feet

Sample Type:
blood sample taken from a vein in your arm; or a random or 24-hour urine sample

Test General info:
The methylmalonic acid (MMA) test measures the amount of MMA in the blood or urine. There is no agreement on whether, blood or urine is best for this test and there are interpretative guidelines and reference levels for each. Your doctor may request both a blood and a urine test at the same time.

MMA is a compound produced in very small amounts during amino acid metabolism. Increased production of MMA is a sensitive and early indicator of vitamin B12 deficiency. Normally, vitamin B12 acts as a coenzyme, promoting the conversion of methylmalonyl CoA to succinyl CoA. If there is not enough B12 available to act as a coenzyme, then methylmalonyl CoA concentrations begin to rise, and the body converts the methylmalonyl CoA to MMA instead. Decreased availability of B12 leads to increases in blood and urine MMA levels. Increased production of MMA in newborn babies may suggest one of the inherited problems collectively called the methylmalonic acidaemias.

Over time vitamin B12 deficiency can cause changes to bone marrow function or the usual composition of blood or blood components. These changes include anaemia with a reduced numbers of larger than normal red blood cells. It can also cause signs and symptoms of disease, inflammation or damage to the peripheral nerves (neuropathy), such as numbness and tingling in the hands and feet and/or mental or behavioural changes (confusion, irritability, depression). Increased concentrations of MMA are often detectable before the occurrence of haematological changes. An affected person may not have any symptoms at all or may have some degree of neuropathy.

The relationship between MMA and B12 has been known for about 40 years, but the use of MMA testing is not widespread because doctors and laboratory scientists do not fully agree on its clinical value. Some in the medical community think that MMA may be a better measure of bioavailable B12 than the usual vitamin B12 test. This is because a relatively large amount of the B12 found in the blood is bound to proteins and is not freely available to act in chemical processes. Some health professionals are convinced that MMA and homocysteine (which may be elevated when either B12 or folate are deficient) are valuable in detecting early and mild cases of B12 deficiency. Others argue that many of the mild deficiencies detected do not progress to more severe deficiencies and do not necessarily need to be identified or treated.


Test Name:
Meticillin Resistant Staphylococcus Aureus screening

Formal Name:
Meticillin Resistant Staphylococcus Aureus screening

When:
en your doctor wants to determine if you are a MRSA carrier (you have no evidence of an active infection) or to determine if MRSA are still present after an infection has been treated with appropriate antibiotic therapy

Test General info:
This collection of tests detects the presence of, and sometimes evaluates the genetic characteristics of, Meticillin Resistant Staphylococcus aureus (MRSA). MRSA are strains of Staphylococcus aureus, or “staph,” bacteria that are resistant to the antibiotic meticillin and to related “beta lactam” antibiotics such as flucloxacillin. First appearing in the early 1960s, MRSA cases and outbreaks have been a problem in confined populations such as hospitals, prisons, and nursing homes ever since. MRSA strains have caused a significant number of severe skin, lung, bone, and heart-related staph infections that have proven difficult to treat and in some cases proven fatal. Most hospitals have instituted measures to attempt to eradicate MRSA and to control the spread of MRSA from person to person. This has been a challenge as staph is a common bacterium that colonizes the skin and in the nose of about 25-30% of the population. In the past, only about 0.8 % of the colonizing staph was MRSA, but in the last decade this has risen above 1%, and a few studies of select populations have shown MRSA colonization rates in those studied as high as 9%.  Since the 1960’s, there have been occasional outbreaks of MRSA outside the hospital setting, but in the last few years the number of cases has greatly increased and concern among doctors and other healthcare workers is growing. In the community, MRSA is causing infections in young, previously healthy people with no apparent risk factors. Studies of these cases and outbreaks are showing that the bacteria is being spread in the community by MRSA colonized or infected people through close contact (such as sports or a day care) and through contact with contaminated objects (such as sports equipment, shared towels, razors, etc.) Often the infection it causes will be a lingering skin ; sometimes it is a lung infection that persists.  Studies have also shown that the community acquired strains of MRSA were frequently genetically distinct from those found in the hospital setting (indicating that they developed separately), resistant to antibiotics routinely prescribed to treat skin infections, and in some cases have proven to be especially virulent, producing toxins and causing an invasive infection. These strains of MRSA are now being found in the hospital as well, as infected and/or colonized patients and healthcare workers bring them into this setting.


Other Names:
MPA [may be referred to by drug names Mycophenolate mofetil or Mycophenolate sodium, or by drug brand names (CellCept, Myfortic)]

Related Tests:
Full Blood Count (FBC), Ciclosporin, Tacrolimus, Sirolimus, Therapeutic Drug Monitoring

Why:
determine the concentration of mycophenolic acid (MPA) in the blood in order to monitor levels, and prevent toxicity

When:
soon as mycophenolate therapy begins and whenever the dose is changed. May be requested frequently at first, then at regular intervals. Whenever excess or deficient levels of MPA are suspected.

Test General info:
This test measures the amount of mycophenolic acid in the blood. Mycophenolic acid is the active metabolite of mycophenolate, a drug that is usually given to patients who have had a heart, kidney, or liver transplant  to help prevent rejection, and sometimes to patients with a variety of autoimmune disorders.  Normally, the immune system defends the body against infections, and can distinguish between “self”, the body’s own constituents, and “nonself”, “foreign” materials.  The immune system recognises a transplanted organ as foreign and begins to attack it.  In the case of autoimmune disorders, the immune system mistakenly targets the body’s own cells and tissues, causing damage and inflammation.  Mycophenolic acid belongs to a group of immunosuppressant drugs and helps to prevent organ rejection, tissue inflammation, and damage.  It acts by reducing the formation of an enzyme that is necessary for increasing the number of lymphocytes (immune cell).  This action will cause a reduction in immune system function and antibody production, reducing the body’s immune response to transplanted organs or to its own tissues and cells.Mycophenolate is given to organ transplant patients in conjunction with other immunosuppressant drugs, such as ciclosporin and tacrolimus. In the treatment of autoimmune disorders, mycophenolate may be used as a single agent (although the patient may also be taking other medications). It may be used for treating conditions such as systemic lupus erythematosus (SLE), vasculitis, rheumatoid arthritis and Crohn’s disease.There are two formulations of the drug available, mycophenolate mofetil and mycophenolate sodium. The drug is broken down in the liver to form first the active drug mycophenolic acid (MPA), and then the inactive compound mycophenolic acid glucuronide (MPAG). Cells in the body turn some of the MPAG back into MPA. Concentrations of MPA in the blood rise when MPA is first formed and then again when some of it is re-formed. Most MPAG, and small amounts of MPA, are removed from the body in the urine.Doctors typically give a standard dose of mycophenolate and then monitor its effect by checking patient’s medical condition. Most immunosuppressants must be maintained within a narrow therapeutic range.  If the concentration is too low, organ rejection may occur; if it is too high, then the patient may develop toxicity. However, the therapeutic range for mycophenolic acid has not yet been definitively established and doctors can manage most patients without the need to measure the concentration of the drug.  When the doctor chooses to monitor mycophenolic acid levels, the mycophenolic acid blood test is usually measured as a “trough” level and correlated to clinical side effects. The ‘trough’ level is collected just before the next dose when the drug is at it’s lowest concentration in the blood.


Related Tests:
Homocysteine, Factor V Leiden Mutation and PT 20210 Mutation,Vitamin B12 & Folate, Cardiac Risk Assessment, Methotrexate

Why:
evaluate the cause of elevated homocysteine levels; sometimes to help determine your risk of thrombosis or premature cardiovascular disease (CVD)

When:
en you have elevated homocysteine levels; sometimes when a close relative has MTHFR gene mutations or has developed CVD or thrombosis at an early age

Test General info:
The methylenetetrahydrofolate reductase (MTHFR) gene oversees the production of the MTHFR enzyme. This enzyme changes one form of folate into another and is part of the process that converts homocysteine into methionine, an important building block for many proteins.MTHFR testing detects two relatively common DNA sequence variants (single nucleotide polymorphisms, SNPs) in the MTHFR gene, C677T and A1298C. These SNPs result in changes in the DNA (or mutations) and are associated with increased homocysteine levels in the blood, which may increase the risk of premature cardiovascular disease (CVD), thrombosis, and stroke. Approximately 10%of the British population is homozygous for C677T. The prevalence is higher in those of Mediterranean and lower in those of African or Indian Asian descent.The C677T variant results in a less active form of the MTHFR enzyme. When a person has two copies of the MTHFR C677T gene mutation (homozygous) or one copy of MTHFR C677T and one copy of A1298C (compound heterozygous), decreased MTHFR enzyme activity slows down the homocysteine-to-methionine conversion process and can lead to a build-up of homocysteine in the blood.The increase in homocysteine is often mild to moderate but will vary from person to person depending upon the amount MTHFR enzyme activity. The rise in homocysteine within the bloodstream is worsened when the affected person is folate-deficient.Results of some studies suggest that high levels of homocysteine in the blood may contribute to risk of CVD by damaging blood vessel walls and promoting formation of plaque (atherosclerosis) and inappropriate blood clots (thrombosis). However, a direct link between homocysteine levels and CVD or thrombotic risk has not been proven. For more on this, see the article on Homocysteine.


Other Names:
Mycoplasma by PCR; Mycoplasma culture; Ureaplasma culture

Formal Name:
Mycoplasma pneumoniae IgG and IgM antibodies; Mycoplasma pneumoniae culture; Mycoplasma culture, genital source; Mycoplasma DNA testing

Related Tests:
Influenza; RSV (Respiratory Syncytial Virus); Legionella; Cold agglutinins; Chlamydia; Gonorrhea

Why:
detect an active or recent mycoplasma infection

When:
en your doctor suspects that your respiratory or systemic symptoms are caused by a mycoplasma infection; when a genital infection may be caused by mycoplasma or ureaplasma

Sample Type:
blood sample drawn from a vein in your arm, a throat swab, sputum sample, body fluid or tissue sample; occasionally, genital or urethral swab

Test General info:
Mycoplasma testing is used to find out whether someone currently has or recently had a mycoplasma infection. It is a group of tests that either measure antibodies in the blood produced in response to a mycoplasma infection or detect the microrganism directly through culturing or by detecting its genetic material (DNA) in a body sample. 

Mycoplasmas are the smallest free-living microorganisms known. They are unlike other types of bacteria (atypical) in many ways and can be difficult to culture and identify. Mycoplasmas may be part of the normal flora found in the throat, upper respiratory tract, and genitourinary tract.

Mycoplasma testing is most often used to detect Mycoplasma pneumoniae (M. pneumoniae), the causative agent of respiratory infections often referred to as ``atypical pneumonia.`` M. pneumoniae is a common cause of upper respiratory infections. It is responsible for 15-20% of cases of community-acquired pneumonia, appearing as single cases and as periodic epidemics – especially in school-age children and in closed populations such as the military. Infections can occur at any time of the year, but outbreaks are more prevalent in the late summer and early autumn.

Most cases of M. pneumoniae infection are mild and self-limited, causing nonspecific symptoms such as bronchitis, a runny nose, and a non-productive cough that may persist for several weeks. Symptoms may become more severe, causing fever, sore throat, headaches, and muscle aches, when the infection spreads to the lower respiratory tract and causes ``walking pneumonia,`` or, more rarely, spreads to other parts of the body. This is especially true in very young infants, in those who have underlying health conditions, such as asthma, or who have compromised immune systems, such as those with HIV/AIDS. Depending upon what parts of the body become infected, complications may range from meningitis to difficulty breathing, cardiac inflammation and arrhythmia, skin rashes, lesions or nodules, arthritis, anaemia, or to Guillain-Barré syndrome.

Testing may occasionally be done to detect other types (species) of mycoplasma. Mycoplasma hominis, Mycoplasma genitalium and Ureaplasma urealyticum (a closely related group of microorganisms) infections are less common than those seen with M. pneumoniae. In adults, these organisms are primarily sexually transmitted, causing non-gonococcal urethritis (NGU) and some inflammation of the prostate (prostatitis) in men and sometimes associated with vaginal discharge and pelvic inflammatory disease (PID) in women. M. hominis and U. urealyticum can be passed from mother to baby during birth when the baby passes through an infected birth canal. They typically colonise infants for their first couple of years. Rarely, they can cause systemic infections in infants and in those with compromised immune systems.


Test Name:
Mycoplasma pneumoniae IgG and IgM antibodies


Why:
determine whether muscle has been injured

When:
you have muscle pain or weakness after muscle damage, particularly if your urine becomes dark reddish-brown in colour

Sample Type:
blood sample taken from a vein in the arm or a random urine sample

Test General info:
Blood is being tested for the presence of myoglobin, a red protein found in muscles. While haemoglobin brings oxygen to most of the body, myoglobin traps oxygen in muscle to allow muscle cells to work properly. When muscle is injured, myoglobin is released into the blood and appears in the urine.


Related Tests:
Chloride; Bicarbonate; Potassium; Electrolytes; Osmolality

Why:
determine the cause of and monitor treatment for illnesses associated with abnormal sodium levels in the body

When:
you are experiencing dehydration, oedema, problems with blood pressure, or have non-specific symptoms; as part of routine laboratory evaluations, or to monitor certain long-term conditions, like high or low blood pressure

Sample Type:
blood sample taken from a vein in the arm or, in some cases, a urine sample

Test General info:
This test measures the concentration of sodium in blood. Sodium is an electrolyte present in all body fluids, and is vital to normal body function. It works to regulate the amount of water in the body, and to control blood pressure by keeping the right amount of water available (in some people, too much sodium from salt in the diet can contribute to high blood pressure). Your body tries to keep your blood sodium within a very small concentration range; it does so by:producing hormones that can increase (such as natriuretic peptides) or decrease (such as aldosterone) sodium losses in urine producing a hormone that prevents water losses (antidiuretic hormone [ADH], sometimes called vasopressin) controlling thirst (even a 1% increase in blood sodium concentration will make you thirsty and cause you to drink water, returning your sodium towards normal.) An abnormal blood sodium concentration is usually due to some problem with one of these systems. When the concentration of sodium in the blood changes, the water content in your body changes. These changes can be associated with dehydration (too little fluid) or oedema (too much fluid, often resulting in swelling in the legs).


Why:
detect the presence or measure the quantity of nicotine or cotinine in blood, urine, saliva, or sometimes hair. To find out whether someone uses tobacco or has been exposed to second-hand smoke. Rarely it can be used to check for acute nicotine poisoning.

When:
enever someone requires confirmation of tobacco usage or exposure to second-hand smoke. Rarely when nicotine overdose is suspected.

Sample Type:
ually a urine sample is collected, but sometimes a blood sample (from a vein in your arm) or a saliva sample is collected. Rarely a hair sample is collected.

Test General info:
Nicotine is an addictive chemical found in the tobacco plant and concentrated in its leaves.  It is inhaled with each puff on a cigarette and ingested with chewing tobacco.  Nicotine is metabolised by the liver into more than 20 compounds, which are removed by the kidneys into the urine. Tobacco use and exposure to tobacco smoke can increase nicotine concentrations in the body.  Cotinine is the body`s main breakdown product (metabolite) of nicotine. Cotinine and nicotine levels also rise with use of nicotine replacement products such as nicotine patches and gums.  In large amounts, nicotineis poisonous. 
Cotinine is usually the best test to check for tobacco use or exposure to tobacco smoke because it lasts longer in the body and is only produced when nicotine is metabolised.  Cotinine has a half-life in the body of between 7 and 40 hours, while nicotine has a half-life of 1 to 4 hours.  Blood and/or urine cotinine tests are usually requested instead of nicotine tests.  The presence of nicotine and/or cotinine in an individual’s sample may indicate the use of tobacco products or exposure to environmental tobacco smoke.  Testing may be used in a number of situations to evaluate the possible use of tobacco products such as in smoking cessation programs, prospective employment assessments and evaluations of applicants for health or life insurance.Nicotine and cotinine testing may also be requested in cases of suspected nicotine poisoning. Acute overdoses of nicotine, such as may happen if a child ingests nicotine lozenges or gum, are relatively rare but generally require immediate medical attention.  Symptoms can include a burning mouth, feeling sick, abdominal pain, salivating (drooling), diarrhoea, sweating, confusion, dizziness, agitation, increased heart rate, rapid or difficult breathing, convulsions, coma, and even death.


Other Names:
(The most common forms of oestrogen tested in clinical laboratories are oestrone [E1], oestradiol [oestradiol-17 beta, E2], and oestriol [E3])

Related Tests:
Follicle stimulating hormone (FSH); luteinising hormone (LH); progesterone; testosterone; AFP & hCG Maternal Screening; sex hormone binding globulin

Why:
measure or monitor your oestrogen levels if you are a woman who has unexplained abnormal menstrual cycles, abnormal or heavy bleeding, infertility problems, symptoms of menopause, or any other hormonal alterations; also it has been used to test for foetal

When:
en your doctor thinks that you have symptoms of a hormone imbalance, abnormal vaginal bleeding, unusual and/or early sex organ development (male and female).

Sample Type:
blood sample taken from a vein in your arm. Occasionally urinary measurements may be required.

Test General info:
Oestrogens are a group of hormones primarily responsible for the development of female sex organs and secondary sex characteristics. While oestrogen is one of the major female sex hormones, small amounts are found in males. In women, follicular stimulating hormone (FSH; produced by the pituitary gland) stimulates cells (follicles) surrounding the eggs in the ovaries, causing them to produce oestrogen. When the oestrogen concentrations reach a certain level, the hypothalamus produces luteinising hormone (LH), which eventually causes the release of the egg, beginning the preparation for fertilisation. 

There are three main forms of oestrogen: oestrone (E1), oestradiol (E2), and oestriol (E3).  Oestrone (E1) is the major oestrogen after the menopause. It is derived from chemicals released from the adrenal gland and is also made in adipose tissue (fat). Oestradiol (E2) is produced in women mainly in the ovary. In men, the testes and adrenal glands are the principal source of oestradiol. Normal levels of oestradiol provide for proper ovulation, conception, and pregnancy, in addition to promoting healthy bone structure and regulating cholesterol levels in females. Oestriol (E3) is the major oestrogen in pregnancy, with relatively large amounts produced in the placenta (from chemicals produced by the baby`s adrenal glands and liver). Oestriol levels start to rise in the eighth week of pregnancy and continue to rise until shortly before delivery. Serum oestriol circulating in maternal blood is quickly removed from of the body by the kidneys. Each measurement of oestriol is a snapshot of what is happening with the placenta and fetus, but there is also natural daily variation in the oestriol level.


Test Name:
Oestrogen and Progesterone receptor status


Test Name:
Often referred to by brand name Rapamune

Other Names:
Often referred to by brand name Rapamune

Related Tests:
Therapeutic Drug Monitoring; Ciclosporin; Tacrolimus; Urea; Creatinine; Electrolytes; Lipid Profile

Why:
determine the concentration of sirolimus in the blood in order to establish a dosing strategy, maintain therapeutic levels, and detect toxic levels

When:
soon as sirolimus therapy begins and whenever dose is changed. Frequently at first, then at regular intervals to monitor concentrations over time. Whenever excess or deficient levels are suspected

Test General info:
This test measures the amount of sirolimus in the blood. Sirolimus is a relatively new immunosuppressive drug that is given to patients who have had an organ transplant. Normally, the immune system recognises a transplanted organ as `foreign` and begins to attack it, leading to rejection.  Sirolimus limits this response and helps prevent organ rejection by inhibiting immune cell activation and prliferation, and antibody production.Siroliums is typically taken by mouth (orally) and, after ingestion, is absorbed from the digestive tract.  The concentration peaks in the blood within a couple of hours and then gradually declines.  Only a small percentage of the dose taken is present in a form that the body can use.  Sirolimus has a half-life of about 60 hours.  It is metabolised by the liver into several new compounds, and is removed from the body in the stool (more than 90%) and urine (less than 2%). Sirolimus is currently approved for use in adults who have kidney transplants.  It appears to be less toxic to the kidneys than other drugs and can be given in conjunction with the other immunosuppressive drugs  ciclosporine and tacrolimus. Studies to evaluate its use in other age groups and types of organ transplantation, such as lung , are in progress. Like other immunosuppressive agents, sirolimus may cause side effects and adverse reactions, and is associated with an increased risk of infection and the development of lymphoma.Sirolimus levels in the blood must be maintained within a narrow concentration range.  If the concentration is too low, organ rejection may occur; if it is too high, then the patient may have symptoms associated with toxicity.  The siroliums blood level is usually measured as `through` level, with blood collection just prior to the next dose - when the drug concentration in the blood is at its lowest.  Typically, sirolimus is given with ciclosporin and corticosteroids.  Dosages must be tailored to the individual, and sirolimus and ciclosporin must both be monitored.  Often, patients will begin with a high dose of sirolimus at the beginning of treatment which is then tapered down to a lower dose.  Ciclosporin is normally reduced or withdrawn after 2-3 months.Sirolimus is usually taken once a day at set intervals.  Food may affect absorption, and the drug should be taken at the same time each day with respect to food.   If ciclosporin is also being taken, then the dosages of both drugs should be separated by several (more than 4) hours.  The sirolimus blood test is usually measured as a “trough” level with blood collection is just prior to the next dose when the drug is at its lowest concentration in the blood.


Test Name:
or by the individual factor number or name


Related Tests:
Sodium; potassium; urea; glucose; alcohol; antidiuretic hormone (ADH); arginine vasopressin (AVP); water deprivation test

Why:
ine and serum osmolality may be measured together to investigate the cause of a low sodium concentration in the blood (hyponatraemia), or a high or low urine output. Serum osmolality may also be measured when ingestion of toxic alcohols such as methanol a

When:
ine and serum osmolality should be tested when an explanation is sought for either i) a low serum sodium concentration ii) an unusually high urine output or iii) an unusually low urine output.Serum osmolality should be tested if poisoning with toxic alcohols is suspected.Stool osmolality may be tested when an explanation for chronic diarrhoea is being sought.

Sample Type:
blood sample taken from a vein in your arm; a urine sample taken at the same time usually helps the doctor to interpret the results

Test General info:
Osmolality is a measure of the number of particles dissolved in a kilogram of fluid. Osmolarity is the number of particles in a litre of fluid. In a dilute fluid osmolality and osmolarity values are approximately the same. An osmotically active substance is any substance that increases the osmolality of a fluid.Measurement of osmolality in serum and urine is used to assess water balance, and whether the body is reacting appropriately to changes in water balance. Water balance in the body is a dynamic process that is regulated by controlling the amount of water excreted in the urine and by regulating the sensation of ``thirst.``Osmotic sensors in the body sense and react to changes in the amount of water and particles in the bloodstream (i.e. factors that alter the osmolality). In health, the osmolality of blood is very closely regulated. When blood osmolality increases, for example in dehydration, the hypothalamus secretes the hormone “antidiuretic hormone” (ADH). ADH signals for the kidneys to conserve water, resulting in formation of concentrated urine (which has a high osmolality). This retention of water dilutes the blood causing a decrease in osmolality back to normal levels. If, on the other hand, blood osmolality decreases (for example following a large drink of water) then ADH secretion is suppressed and the kidneys excrete increased amounts of dilute urine. This results in a decrease in the amount of water in the body, and so blood osmolality rises to normal.Osmolality can be directly measured in the laboratory using an osmometer.Normally, the major particles contributing to osmolality in serum are sodium and potassium salts, glucose and urea. Therefore osmolality can be approximated by the following equation:Calculated Serum Osmolality = 2 (sodium + potassium) + glucose + ureaWhen all values are in mmol/L. Note, there are several variations of this calculation in use.The calculated and measured osmolality can be compared to determine if there are other particles present (in addition to sodium, potassium, glucose and urea) that contribute to the measured serum osmolality. The difference between measured and calculated (estimated) osmolality is called the ``osmotic gap`` or ``osmolal gap.`` An increase in the osmotic gap (greater than 10) indicates the presence of other substances such as toxic alcohols, aspirin, or mannitol.Osmolality of the urine is used as a measure of the kidneys ability to concentrate urine. Urine osmolality is largely due to the presence of urea and creatinine. The more concentrated the urine is, the higher its osmolality.


Related Tests:
HIV antibody test; HIV resistance testing; HIV viral load; CD4 and CD8 lymphocyte counts

Why:
check for infection with HIV after a recent exposure or to monitor your body’s response to anti-HIV therapy

Sample Type:
blood sample taken from a vein in your arm or by a finger-prick

Test General info:
The p24 antigen test identifies actual HIV particles in blood (p24 is a protein ``shell`` on the surface of HIV). However, the p24 test is generally positive only from about one week to 3 or 4 weeks after infection with HIV. The p24 protein cannot be detected until about a week after infection because it generally takes that long for the virus to multiply sufficiently to be detected. The p24 protein then becomes undetectable again after sufficient antibodies to HIV have been produced to bind the p24 protein and eliminate it from the blood. At that point the standard HIV antibody test becomes positive. Often years later in the course of HIV, when AIDS (acquired immunodeficiency syndrome) develops and antibody production falls, the p24 protein may again become detectable.


Why:
help diagnose sepsis in a person who is critically ill; to help determine the risk of severe sepsis leading to septic shock in a person who has sepsis; to distinguish bacterial from non-bacterial infections

When:
en someone is seriously ill and a doctor wants to distinguish between sepsis and other causes of the illness; to help guide treatment in a patient with sepsis

Test General info:
This test measures the amount of procalcitonin in the blood. Procalcitonin is made during the process of producing the thyroid hormone calcitonin. It is normally produced by special cells in the thyroid gland called C-cells and is present in low levels in the blood. However, it may also be made by other cells in the body when stimulated by certain disease processes, in particular whole body bacterial infaction (systemic bacterial infection or sepsis) as opposed to just local bacterial infections. Other reasons for increased procalcitonin include infection from other causes, tissue damage due to events such as trauma, surgery, pancreatitis, burns, heart attack; and rapid and severe organ (kidney, heart, lung etc) transplant rejection.

Levels of procalcitonin in the blood increase rapidly and to high concentrations when a person has sepsis. They are not as particularly increased when a person has a viral infection or other illnesses which may have the same or similar symptoms as sepsis. Difference in stimulous gives procalcitonin the potential to be used to help detect severe bacterial infection at an early stage and to be able to distinguish between a bacterial infection and another cause of a serious illness.


Related Tests:
Pleural fluid analysis, Peritoneal fluid analysis, Gram stain, Susceptibility testing, Protein, Albumin, Glucose, AFB smear and culture

Why:
help diagnose the cause of inflammation of the pericardium and/or fluid accumulation around the heart

When:
en a doctor suspects that someone has a condition associated with inflammation of the pericardium and/or fluid accumulation around the heart

Test General info:
Pericardial fluid is a liquid that acts as a lubricant for the movement of the heart. It is found in small quantities between the two layers of the pericardium. Pericardial fluid is produced by mesothelial cells in the membranes and reduces friction as the heart pumps blood.A variety of conditions and diseases can cause inflammation of the pericardium (pericarditis) and/or excessive accumulation of pericardial fluid (pericardial effusion). Pericardial fluid analysis is a group of tests used to help find the cause of the problem. There are two main reasons why fluid may collect in the pericardial space:Fluid may accumulate because of an imbalance between the pressure within blood vessels—which drives fluid out of blood vessels—and the amount of protein in blood—which keeps fluid in blood vessels. The fluid that accumulates in this case is called a transudate. Transudates are most often caused by cirrhosis of the liver or congestive heart failure. Fluid accumulation may be caused by injury or inflammation of the peritoneum, in which case the fluid is called an exudate. This type of fluid may be the result of conditions such as infection, cancer (metastatic cancer, lymphoma, mesothelioma), rheumatoid disease, or systemic lupus erythematosus. It is important to distinguish between the two types of fluid because it helps diagnose the disease or condition. Doctors use an initial set of tests (cell count, protein or albumin and appearance of the fluid) to distinguish between transudates and exudates. Once the sort of fluid has been identified, additional tests may be done to help pinpoint the disease or condition causing pericarditis and/or pericardial effusion.


Test Name:
Peripheral blood smear, manual differential, red blood cell morphology


Related Tests:
Pleural fluid analysis, Pericardial fluid analysis, Gram stain, Susceptibility testing, Glucose, Albumin, WBC count, RBC count, AFB smear and culture

Why:
help diagnose the cause of peritonitis and/or peritoneal fluid accumulation (ascites)

When:
en a doctor suspects that someone with abdominal pain and swelling, nausea, and/or fever has a condition associated with inflammation of the peritoneum (peritonitis) or peritoneal fluid accumulation

Test General info:
Peritoneal fluid is a liquid that acts as a lubricant in the abdominal cavity. It is found in small quantities between the layers of the peritoneum. Peritoneal fluid is produced by mesothelial cells in the membranes and acts to moisten the outside of the organs and to reduce the friction of organ movement during digestion.A variety of conditions and diseases can cause inflammation of the peritoneum (peritonitis) and/or excessive accumulation of peritoneal fluid (peritoneal effusion or ascites). Peritoneal fluid analysis comprises a group of tests used to help find the cause of the problem. There are two main reasons why fluid may collect in the abdominal cavity:Fluid may accumulate because of an imbalance between the pressure within blood vessels—which drives fluid out of blood vessels—and the amount of protein in blood—which keeps fluid in blood vessels. The fluid that accumulates in this case is called a transudate. Transudates are most often caused by cirrhosis or congestive heart failure.Fluid accumulation may be caused by injury or inflammation of the peritoneum, in which case the fluid is called an exudate. This type of fluid may be the result of conditions such as infection, cancer (metastatic cancer, lymphoma, mesothelioma), rheumatoid disease, or systemic lupus erythematosus.Differentiation between the types of fluid is important because it helps diagnose the specific disease or condition. Doctors use an initial set of tests (cell count, albumin and appearance of the fluid) to distinguish between transudates and exudates. Once the fluid is determined to be one or the other, additional tests may be performed to further pinpoint the disease or condition causing peritonitis and/or ascites.


Why:
find out if the phenobarbital level in the blood is at an appropriate level for an individual patient

When:
regular intervals to monitor phenobarbital levels in the blood and if needed to detect low or toxic levels

Test General info:
This test measures the level of phenobarbital in the blood. Phenobarbital is a barbiturate, a sedating drug that depresses the nervous system. Doctors usually prescribe phenobarbital to prevent fits or to relieve anxiety. Phenobarbital is often prescribed to treat epilepsy and other seizure disorders because the drug stabilizes electrical activity in the brain. Patients may become dependent on the drug after prolonged use.Your doctor will monitor your response to phenobarbital to make sure that you have the desired level of the drug in your bloodstream and to find out what is the best dose for you. Monitoring the level also helps assure your doctor that the level of the drug circulating in your bloodstream is not toxic. Your doctor might request a phenobarbital level when you begin taking the drug, and any time while on the drug, to find out if the dose is right for you. Your doctor might also decide to request a test if you begin taking another medicine because several common drugs can affect how your body responds to phenobarbital. The following drugs can have effects with phenobarbital:oral blood-thinning medications like warfarinantidepressantscentral nervous system depressants, sedatives, hypnotics and tranquillisersantihistaminesalcoholoral contraceptivescorticosteroids like prednisonedoxycycline used to treat bacterial infections griseofulvin, a drug used to treat fungal infections phenytoin, another medication often prescribed to treat seizures. It is important for you to have a constant level of phenobarbital in the blood that is within the “target” range. If your level is too low, you may experience fits or anxiety. If the level is too high, you could experience side effects or toxicity . Maintaining a constant, therapeutic level of phenobarbital in the blood can be difficult. Phenobarbital is metabolised by liver enzymes and removed in the urine at different rates, depending on your age and overall health. Depending on dose, age and health, full removal can take several days to weeks. Once the body has reached its capacity to metabolise phenobarbital, small increases in dose can result in large increases in levels of the drug in the blood. Side effects can become more severe, and toxicity may occur.


Formal Name:
Plasma free metadrenalines (normetadrenaline and metadrenaline)

Why:
help diagnose or rule out a phaeochromocytoma

When:
en you have persistent or episodic high blood pressure and symptoms such as headaches, rapid heart rate, and sweating

Test General info:
The plasma free metadrenalines test measures the amount of metadrenaline and normetadrenaline in the blood. These substances are metabolites of adrenaline (epinephrine) and noradrenaline (norepinephrine). Adrenaline and noradrenaline are catecholamine hormones that help regulate the flow and pressure of blood throughout the body and play important roles in the body`s response to stress.Catecholamines are produced in the adrenal medulla – the interior portion of the adrenal glands – and secreted into the blood. Once these hormones have completed their actions, they are metabolised to inactive compounds. Noradrenaline breaks down into normetadrenaline and hydroxymethylmandelic acid (HMMA) (also called vanillylmandelic acid (VMA)), and adrenaline becomes metadrenaline and HMMA. Both of the catecholamines and their metabolites are normally found in small fluctuating quantities in the blood and urine.A rare tumour called a phaeochromocytoma can produce large amounts of catecholamines, resulting in significantly increased concentrations of metadrenaline and normetadrenaline. About 80-85% of phaeochromocytomas form in the adrenal glands and, while a few are cancerous, most are benign – they continue to grow but usually do not spread beyond their original location.The catecholamines produced by phaeochromocytomas can cause persistent hypertension and episodes of severe high blood pressure. This can cause symptoms such as headaches, palpitations, sweating, nausea, anxiety, and tingling in the extremities. Left untreated, the symptoms may worsen as the pheochromocytoma grows. Over time, hypertension caused by the tumour may cause kidney damage, heart disease, and raise the risk of a stroke or heart attack.Several tests, including plasma free metadrenalines, can detect the presence of phaeochromocytomas. Although they are rare, it is important to diagnose these tumours because they cause a potentially curable form of hypertension. In most cases, the pheochromocytomas can be surgically removed, which eliminates the high blood pressure and its associated symptoms and complications.


Related Tests:
Erythrocyte sedimentation rate (ESR); C-reactive protein (CRP); fibrinogen; immunoglobulins; protein electrophoresis

Why:
detect and monitor inflammation, to help diagnosis and monitoring many conditions. To estimate the stickiness of the blood caused by abnormal proteins (“paraproteins”).

When:
en your doctor thinks that you might have a condition that causes inflammation and to help diagnose and follow the course of this condition, especially temporal arteritis or polymyalgia rheumatica. To monitor whether paraproteins are causing clinically important stickiness of the blood which is likely to affect the circulation.

Sample Type:
blood sample taken from a vein in the arm.

Test General info:
Plasma viscosity is an indirect measure of the amount of protein present in the plasma (liquid) part of the blood. It can reflect the degree of inflammation present in the body. It can also detect the presence of abnormal paraproteins which can be made by benign or malignant tumours. It actually measures the force needed to send a fixed amount of plasma flowing along a thin tube in a given time, at a standard temperature. Typically, distilled water at 20C will have a viscosity of 1.00mPas (milli-Pascal-second), whereas normal plasma at 37C may have a viscosity of around 1.7mPas . The higher the result, the “stickier” the blood is. Increased blood levels of certain proteins, such as fibrinogen, which is increased in inflammation, or immunoglobulins, which are increased in inflammation or secreted by some tumours, cause the plasma viscosity to rise.


Related Tests:
FBC, Platelet aggregation, Platelet Function Tests, Blood Film, von Willebrand Factor, HIT Antibody, Coagulation Factors, PT, aPTT, JAK2

Why:
count the number of platelets present in blood. This may be performed if there are symptoms of a bleeding disorder, an unexplained blood clot, or to check that the bone marrow is working as it should.

When:
e platelet count is performed as part of a full blood count (FBC) analysis, which may be carried out as a general screen during routine healthcare examinations or for the diagnosis or monitoring of diseases that affect the blood and bone marrow.

Test General info:
Platelets are small cell fragments and are found in the blood along with red cells and white cells. Platelets are produced in the bone marrow and released into the blood where they play an important role in coagulation (blood clotting), helping to stop bleeding when blood vessels are injured. They are the first cells to be recruited to sites of injury and, when activated, they clump together (aggregate), sealing the blood vessel and forming a blood clot. These small, disc-shaped cells usually live for around 5-10 days in the blood before they are destroyed.Platelets are very important for efficient blood coagulation and preventing unnecessary or excessive blood loss. If there are too few platelets, or if the platelets that are present don’t function properly, then there may be problems with blood clot formation. On the other hand, too many platelets can increase the risk of blood clots that can block blood vessels and cause organ damage.The platelet count simply provides information on the number of these cells that are present in blood; it does not reveal if these cells are functioning properly. Specialised tests, called the platelet function tests, are used when there is suspicion of a platelet function defect.


Related Tests:
Pericardial Fluid Analysis; Peritoneal Fluid Analysis; Gram Stain; Susceptibility Testing; Protein; Albumin; Glucose; AFB Smear and Culture

Why:
help diagnose the cause of inflammation of pleurae (pleuritis, pleurisy), accumulation of fluid in the pleural space (pleural effusion), or possible malignancy

When:
en a doctor suspects that someone with chest pain, coughing, and/or difficulty breathing has a condition associated with pleuritis and/or pleural effusion

Test General info:
Pleural fluid is found in the pleural cavity and serves as a lubricant for the movement of the lungs during inhalation and exhalation. It is derived from a plasma filtrate from blood capillaries and is found in small quantities between the layers of the pleurae – membranes that cover the chest cavity and the outside of each lung.A variety of conditions and diseases can cause inflammation of the pleurae (pleuritis) and/or excessive accumulation of pleural fluid (pleural effusion). Pleural fluid analysis is a group of tests used to help find the cause of the problem. There are two main reasons why fluid may collect in the pleural space:Fluid may accumulate in the pleural space because of an imbalance between the pressure within blood vessels—which drives fluid out of blood vessels—and the amount of protein in blood—which keeps fluid in blood vessels. The fluid that accumulates in this case is called a transudate. This type of fluid usually involves both lungs and is often a result of either cirrhosis of the liver or congestive heart failure. Fluid accumulation may be caused by injury or inflammation of the pleurae, in which case the fluid is called an exudate. It usually involves one lung and may be seen in infections (pneumonia, tuberculosis, sarcoidosis), malignancies (lung cancer, metastatic cancer, lymphoma, mesothelioma), rheumatoid disease, or systemic lupus erythematosus. Differentiation between the types of fluid is important because it helps diagnose the specific disease or condition. Doctors use an initial set of tests (cell count, albumin and appearance of the fluid) to distinguish between transudates and exudates. Once the fluid is determined to be one or the other, additional tests may be performed to further pinpoint the disease or condition causing pleuritis and/or pleural effusion.


Test Name:
Potassium hydroxide preparation, Fungal culture, Fungal antigen and antibody tests, and Calcofluor white stain


Other Names:
Transthyretin; tryptophan-rich prealbumin; thyroxine-binding prealbumin

Why:
help assess patients with malnutrition and to monitor patients receiving nutrition support

When:
your doctor suspects you are malnourished because of poor diet, HIV, or an eating disorder; if you are about to be admitted to the hospital for surgery; if are hospitalised with certain diseases; or if you are having parenteral nutrition or kidney dialysis

Test General info:
The test measures levels of prealbumin, an important protein found in the blood and produced mainly by the liver. Prealbumin breaks down quickly in the body and therefore the amount in the blood changes rapidly and can provide an immediate picture of your  nutritional status.


Why:
st commonly, to help determine the cause of infertility, by assessing whether you have ovulated. May also be used in other situations, such as, to help diagnose an ectopic or failing pregnancy or to help diagnose the cause of abnormal uterine bleeding

When:
specific times during a woman’s menstrual cycle (period) to determine whether/when she is ovulating and producing eggs, and sometimes during early pregnancy if symptoms suggest an ectopic or failing pregnancy.

Test General info:
This test measures the concentration of progesterone in the blood. Progesterone is a hormone whose main role is to help prepare a woman’s body for pregnancy; it works together with several other female hormones.On a monthly basis, the hormone oestrogen causes the endometrium (the lining of the womb, or uterus) to grow and replenish itself, while a surge in luteinising hormone (LH) leads to the release of an egg from one of the two ovaries. The corpus luteum (a small yellow mass of cells) then forms in the ovary at the site where the egg was released and begins to produce progesterone. This progesterone stops endometrial growth and prepares the uterus for the possible implantation of a fertilised egg. If menstrual cycles are regular and conform to a standard 28 day length, progesterone concentrations will normally peak on approximately day 21 of the cycle (with day 1 being the first day of menstruation).If fertilisation does not occur, the corpus luteum degenerates, progesterone concentrations fall, and menstrual bleeding begins. If a fertilised egg is implanted in the uterus, the corpus luteum continues to produce progesterone. After several weeks, the placenta replaces the corpus luteum as the main source of progesterone, producing relatively large amounts of the hormone throughout the rest of a normal pregnancy.


Related Tests:
FSH, LH, Testosterone, Oestrogen, Progesterone

Why:
determine whether or not your prolactin concentrations are higher (or occasionally lower) than normal

When:
en you have symptoms of an elevated prolactin, such as galactorrhoea (breast milk production, not during pregnancy) and/or visual disturbances and headaches; as part of investigation for female and male infertility; for follow up of low testosterone in men

Test General info:
Prolactin is a hormone produced by the anterior pituitary gland, a grape-sized organ found at the base of the brain. Prolactin concentrations are regulated by dopamine (a brain chemical), and the hormone is normally present in low amounts in men and non-pregnant women. Its main role is to promote lactation (breast milk production).Prolactin concentrations are usually high throughout pregnancy and just after childbirth. During pregnancy prolactin, oestrogen and progesterone stimulate breast milk development. Following childbirth, prolactin helps initiate and maintain the breast milk supply. If a woman does not breastfeed, her prolactin concentration will soon drop back to pre-pregnancy levels. If she does breastfeed, suckling by the infant plays an important role in the release of prolactin. When the baby feeds, this has an effect on the amount of prolactin secreted by the pituitary, and this is turn controls the amount of milk produced. Prolactin concentrations will continue to be high while the mother continues to breastfeed, but will eventually fall back to pre-pregnancy levels.Besides pregnancy, the most common cause of elevated prolactin concentration is a prolactinoma, a prolactin-producing tumour of the pituitary gland. Prolactinomas are the most common type of pituitary tumour and are usually benign. They develop more frequently in women but are also found in men. Problems can arise both from the unintended affects of excess prolactin, such as milk production in the non-pregnant woman (and rarely, man) and from the size and location of the tumour.If the pituitary gland and/or the tumour enlarge significantly it can put pressure on the optic nerve, causing headaches and visual disturbances; and it can interfere with the other hormones that the pituitary gland produces. In women, prolactinomas can cause infertility and irregularities in menstruation; in men, these tumours can cause a gradual loss in sexual function and desire. If left untreated, prolactinomas may eventually damage tissues surrounding them.


Why:
look for certain liver, kidney disorders and several other diseases

When:
your doctor thinks that you have symptoms of a liver or kidney disorder

Test General info:
The total protein test is a rough measure of all of the proteins in the plasma portion of your blood. Proteins are important building blocks of all cells and tissues; they are important for body growth and health. Total protein measures the combined amount of two classes of proteins, albumin and globulin. Albumin is a carrier of many small molecules, but its main purpose is to keep fluid from leaking out of blood vessels, while globulin proteins include enzymes, antibodies, and more than 500 other proteins.


Formal Name:
Protein C Functional or Antigen; Protein S Free (Functional) or Antigen (Total)

Related Tests:
Factor V Leiden; Prothrombin 20210 gene mutation, Homocysteine, Lupus Anticoagulant, Antithrombin Activity

Why:
help evaluate a thrombotic episode, to determine whether you may have an inherited or acquired Protein C or Protein S deficiency

When:
en you have had an unexplained thromboembolism (a blood vessel blocked by a blood clot), when your newborn has a severe clotting disorder, such as disseminated intravascular coagulation (DIC) or purpura fulminans. Sometimes when a close relative has an inherited Protein C or Protein S deficiency

Test General info:
Proteins C and S help adjust the rate of blood clot formation. When a blood vessel or tissue is injured, the body initiates the coagulation cascade - a step by step process involving the activation of platelets and of up to 20 protein factors - which results in the formation of a stable blood clot. This clot prevents additional blood loss and protects the injury until it heals. Once it is no longer needed other factors break the clot down so that it can be removed.
Thrombin is a clotting factor that can accelerate or decelerate blood clot formation by promoting or inhibiting its own activation. It forms a feedback loop that uses Protein C and Protein S to slow down the coagulation cascade. Thrombin first combines with a protein called thrombomodulin, then activates Protein C. This activated Protein C (APC) then combines with Protein S (a cofactor) and together they work to degrade coagulation factors VIIIa and Va (these activated factors are required to produce thrombin). This has the net effect of slowing down the generation of new thrombin and inhibiting further clotting. If there is not enough Protein C or Protein S, or if either one is not functioning normally, then thrombin generation goes on largely unchecked. This can lead to excessive or inappropriate clotting that may block the flow of blood in the veins (VTE - venous thromboembolism) and, more rarely, in the arteries.
Problems with Protein C and Protein S can be inherited or acquired.There are two types of Protein C deficiencies:Type 1 is related to quantity
Type 2 to abnormal function.Protein S exists in 2 forms, free and bound, but only the free Protein S is available to combine with Protein C.There are 3 types of Protein S deficiencies:Type 1 deficiency is due to an insufficient quantity
Type 2 to abnormal function
Type 3 to a shift from free Protein S to bound Protein S.Decreased Protein C and Protein S quantity may be related to insufficient production or to increased use. Since both proteins are produced in the liver and are vitamin K dependent; liver disease, a shortage of vitamin K, or anticoagulant therapy that opposes vitamin K, may result in reduced Protein C and/or Protein S levels. Conditions such as disseminated intravascular coagulation (DIC) that cause clotting and bleeding throughout the body use up clotting factors, including Protein C and Protein S, at an increased rate, and so, decrease their concentrations in the blood.
Although inherited mutations in the genes that produce Protein C and Protein S are relatively rare, they can result in:a decreased level of Protein C or Protein S being produced, an abnormal protein that either cannot bind properly to its cofactor (C or S) an abnormal protein which when combined, does not degrade factors VIIIa and Va normallyWhen these mutations occur, they are independent of each other and the mutation is most likely to be in one of Protein C or Protein S. Changes in the gene may be heterozygous (one mutated copy of the C or S gene) or homozygous (two changed copies of C or S). A heterozygous change raises the risk of developing a VTE by a moderate amount but a homozygous change in either gene can cause severe clotting – it may cause life threatening purpura fulminans or DIC in the newborn, and it requires a lifetime of vigilance against recurrent thrombotic episodes.


Related Tests:
hCG; First Trimester Down Syndrome Screen; Amniotic Fluid Analysis; Chromosome Analysis

Why:
assess the risk of a foetus having certain chromosomal abnormalities, such as Down syndrome (trisomy 21) or Edward’s syndrome (trisomy 18).

When:
most centres women will be offered first trimester screening between 11-13 weeks, although for some it may be carried out in the second trimester, usually between 14 and 20 weeks of pregnancy.

Sample Type:
blood sample taken from a vein in the arm. The results from the laboratory may be combined with the results from an ultrasound scan to improve the overall effectiveness of the screening test.

Test General info:
The screening tests involve the measurement of different proteins and hormones found in mother’s blood. In addition, the mother is asked to provide additional information about herself that is used to improve the accuracy of the screening test, such as her age, weight, ethnicity, smoking status and whether she has diabetes. The following blood tests may be performed as part of second trimester screening:Alpha fetoprotein (AFP) is a protein produced by the developing baby. AFP moves from the baby across the placenta and amniotic membranes into the mother and appears in the maternal blood. Levels in the mother’s blood tend to rise throughout the first half of pregnancy.Total of free beta human chorionic gonadotrophin (hCG) are hormones produced by the placenta. Levels in mother’s blood rise early in pregnancy and then fall later on.Unconjugated oestriol (uE3) is a hormone produced by the baby as well as by the placenta. Levels gradually increase through the first and second trimester of pregnancy.Inhibin-A is a hormone produced by the placenta. Levels rise during the first trimester of pregnancy and are generally constant in the second trimester.The tests may be known by different names depending on how many tests are performed. For example, the triple test combines the results of three tests (AFP, hCG and uE3) while the quadruple test combines the results of four tests (AFP, hCG, uE3 and Inhibin-A).


Related Tests:
Full blood count (FBC), Haemoglobin, Haematocrit (PCV), Blood Film, Iron Tests, Reticulocyte Count, Vitamin B12 and Folate, Bone Marrow Aspiration and Biopsy, G6PD, Erythropoietin

Why:
evaluate any change in the number of red blood cells in your blood

When:
part of a full blood count (FBC), which may be requested for a variety of reasons.

Test General info:
This test counts the number of red blood cells (RBC) in a litre of blood. Red blood cells, which are made in the bone marrow, carry oxygen from the lungs to the cells and transport carbon dioxide from the cells to the lungs. Women tend to have lower RBC counts than men, and levels tend to decrease with age. When the value decreases by more than 10% of the expected normal value, the patient is said to be anaemic.


Related Tests:
Influenza tests; Pertussis; Strep throat

Why:
determine whether an infant, an elderly patient, or an immunocompromised patient has respiratory syncytial virus (RSV) and to help determine whether or not RSV season has started in your community

When:
en it is RSV season (late autumn until early spring) and your doctor wants to determine whether your runny nose, congestion, coughing and/or difficulty breathing are due to RSV or to other causes

Test General info:
RSV testing is used to detect respiratory syncytial virus, a common viral respiratory infection. RSV tends to be seasonal, causing community epidemics in young children, older adults, and immunocompromised patients that typically begin in November or December and disappear in early spring. In these high-risk groups, RSV can cause pneumonia and bronchiolitis. Affected patients may have symptoms such as severe coughing, difficulty breathing, and high fevers.RSV testing detects virus that is being shed in the respiratory/nasal secretions of an infected person. Since detectable amounts of virus are usually only shed for the first few days of an infection, most testing must be done during this time period. There are several methods to test for the virus, but rapid RSV antigen testing is by far the most popular. Rapid RSV antigen tests are frequently performed on-site, in the doctor’s office or the emergency room, with most results available within an hour. In some cases, the sample may be collected and sent to a laboratory for a more sensitive testing method. Results of these RSV tests are usually available the same day.Occasionally, samples will be sent to detect the virus’s genetic material. These tests have the advantage of identifying not only the RSV virus but also other respiratory viruses that may be present. The main disadvantages of these tests are that they are not available in every laboratory and that the results take longer than the rapid RSV test. This makes them less clinically useful for evaluating an individual patient, but they can be useful for documenting that RSV or another virus, such as influenza, has reached a community and for identifying outbreaks in particular populations, such as a nursing home, school, or neighbourhood.


Related Tests:
Full blood count (FBC), Vitamin B12 and Folate, Vitamin D, Iron Tests, Retinol-Binding Protein (RBP)

When:
en a person has symptoms suggesting vitamin A deficiency or excess, or is at risk for vitamin deficiency

Test General info:
This test measures the concentration of retinol in the blood; retinol is the primary form of vitamin A in animals. Vitamin A is an essential nutrient required for healthy vision, skin growth and integrity, bone formation, immune function, and embryonic development. It is required to produce photoreceptors in the eyes and to maintain the lining of the surface of the eyes and other mucous membranes. Deficiencies in vitamin A can impair night vision, cause eye damage, and in severe cases lead to blindness. Acute or chronic excesses of vitamin A can be toxic, cause a range of symptoms, and sometimes lead to birth defects.The body cannot make vitamin A and must rely on dietary sources of vitamin A. Meat sources provide vitamin A (as retinol), while vegetable and fruit sources provide carotene (a substance that can be converted into vitamin A by the liver). Vitamin A is stored in the liver and fat tissues (it is fat-soluble), and healthy adults may have as much as a year`s worth stored. The body maintains a relatively stable concentration in the blood through a feedback system that releases vitamin A from storage as needed and increases or decreases the efficiency of dietary vitamin A absorption.Deficiencies in vitamin A are rare in the United Kingdom, but they are a major health problem in many developing countries where high numbers of people have limited diets. One of the first symptoms of vitamin A deficiency is night blindness. In a 1995-2005 review of the global prevalence of vitamin A deficiency in populations at risk, the World Health Organisation estimated that night blindness affected as many as 5 million preschool age children and nearly 10 million pregnant women. In addition to this, they estimated that another 190 million preschool age children and 19 million pregnant women were at risk of vitamin A deficiency, with low retinol concentrations that reflected an inadequate supply of vitamin A.In the UK, deficiencies are primarily seen in those with malnutrition, with malabsorption disorders such as coeliac disease, cystic fibrosis, or chronic pancreatitis, in the elderly, and in those with alcoholism and liver disease.Vitamin A toxicity occurs primarily from overuse of vitamin supplements. However, it can sometimes occur when the diet includes a high proportion of foods from animal sources that are high in vitamin A, such as liver.


Related Tests:
ANA; Autoantibodies; CCP (Cyclic Citrullinated Peptide Antibody)

Why:
help diagnose rheumatoid arthritis (RA) and Sjögren’s syndrome

When:
en your doctor thinks that you have symptoms suggestive of RA or Sjögren’s syndrome

Test General info:
This test detects and measures rheumatoid factor (RF), a type of “autoantibody”, in the blood. We all have antibodies (also known as immunoglobulins) in our blood, which are protective proteins which defend the body against infection, particularly from bacteria. However, “autoantibodies” may attack the patient’s own tissues mistakenly identifying them as “foreign”. While the role of RF is not well understood, it may not directly cause joint damage, but promote the body`s inflammation reaction which in turn contributes to autoimmune joint destruction.  The RF test is sensitive but not very specific, implying it can be found in diseases other than rheumatoid arthritis (RA).  It is most closely associated with RA but may also be present in other autoimmune disorders, such as Sjögren’s syndrome, in some persistent bacterial and viral infections, and can be found in a small percentage of healthy people particularly in the elderly.


Other Names:
Salicylates, aspirin, acetylsalicylic acid, methyl salicylate

Related Tests:
INR (International Normalised Ratio, prothrombin time)

Why:
detect aspirin overdose and guide hospital treatment or to monitor aspirin therapy of inflammatory disease such as rheumatoid arthritis to guard against overdosage

When:
en you have symptoms such as nausea, rapid breathing, ringing in the ears (tinnitus), or confusion that may be from taking too much aspirin or medications with salicylate ingredients; when it is suspected that your child may have ingested a significant quantity of a salicylate; at regular intervals when monitoring an overdose; sometimes on a regular basis if you take a salicylate on prescription for rheumatoid arthritis or another autoimmune disorder

Test General info:
Salicylates are a group of drugs, including aspirin, available as both prescription and non-prescription (over-the-counter) medications. They are often used to relieve pain and inflammation, to reduce fever, and to prevent excessive blood clotting. Salicylate testing measures the concentration in the blood to detect and/or monitor an overdose (salicylate poisoning).Aspirin is the most common salicylate, but there are others, including methyl salicylate, which is found as oil of wintergreen in some muscle ache creams. Methyl salicylate creams and topical forms of aspirin are absorbed into the body through the skin. After oral forms of salicylates are ingested, they are converted to salicylic acid, absorbed in the stomach and small intestine and transferred into the blood stream.With single, normal doses, blood concentrations typically reach a maximum in about 2 hours, but this may be delayed for 12 hours or more with ``enteric-coated`` or ``sustained-release`` preparations. If too much salicylate is ingested at one time (acute toxicity) or too much is taken over a period of time (chronic toxicity), and/or if the body`s ability to remove the salicylates is reduced, then signs and symptoms associated with toxicity will begin to emerge. The ability to remove salicylates efficiently is affected by the body`s blood and urine pH (acidity/alkalinity) and by kidney function.Over-the counter salicylates are used as needed or regularly to reduce pain, fever, and inflammation. Low doses of aspirin may be taken on a regular basis to reduce the chance of inappropriate blood clotting (thrombosis), heart attack, or stroke in people who are at risk. Aspirin may also be used to reduce the risk of complications in someone who is having a heart attack, or who has recently experienced one. Aspirin is also used in patients with myeloproliferative neoplasms (e.g. polycythaemia vera, essential thrombocythaemia). Aspirin is now rarely used to relieve symptoms of rheumatoid arthritis (RA) and osteoarthritis as well as symptoms of autoimmune disorders such as systemic lupus erythematosus.When used with care and following dosing directions, therapeutic doses of salicylates are safe and effective for most adults. Excessive amounts of salicylates, however, can be toxic, affecting breathing and disrupting the body`s acid-base balance. In severe cases, toxicity can cause convulsions, coma, and even death.Adults can experience problems with salicylate toxicity when they unknowingly combine multiple products that contain them. Many over-the-counter medications include a salicylate as one of the ingredients. An individual who is unaware of the ingredients can mistakenly take more than one of these drugs together, resulting in a cumulative effect and a high amount of ingested salicylate. Widespread and easy availability of salicylate-containing medications can also mislead some to think that it is very safe and that ``more is better.`` An overdose can occur when someone has pain that is not relieved with an initial dose and, unaware of the danger, takes more than the recommended dose and/or takes additional doses too frequently. In the elderly, these scenarios can especially be a problem because underlying conditions and general health status can decrease the ability to eliminate salicylates.Aspirin is not recommended for use in children and adolescents (under 16) because of the risk of developing Reye’s syndrome, a disease characterized by acute brain damage and liver dysfunction that can be fatal. Though young people are not routinely given aspirin, they may become poisoned through accidental or intentional ingestion. Topical creams that contain methyl salicylate or other salicylates are of special concern as they contain very high doses.


Test Name:
Salicylates, aspirin, acetylsalicylic acid, methyl salicylate


Other Names:
Sperm analysis; sperm count; seminal fluid analysis

Related Tests:
Antisperm antibody test; FSH; LH; Testosterone; Prolactin

Why:
investigate to see if there is a problem with your fertility. This is often performed if your partner is having trouble becoming pregnant.It is also necessary after a vasectomy operation to ensure that the sterilisation operation was successful and that y

When:
men analysis - When you think you might have a fertility problem.Post-vasectomy semen analysis – 16 weeks after the vasectomy with at least 24 ejaculations since the operation.

Sample Type:
semen sample collected in a sterile container provided by the laboratory or doctor. It is important that the specimen container has been tested to ensure it is not toxic to sperm.

Test General info:
A semen analysis measures the quantity and quality of the fluid released from the penis during ejaculation. It evaluates both the liquid portion, called semen, and the microscopic moving cells, called spermatozoa (sperm).Semen is the turbid, whitish liquid that contains sperm and the products from several glands. It is normally fairly thick after ejaculation and then becomes thinner within ten to thirty minutes. Sperm are the reproductive cells in semen that have a head and a tail. Each sperm contains one copy of each chromosome (all of the male’s genes). Sperm are motile (can move independently) and this allows them to travel to and fuse with the female’s egg, resulting in fertilisation. In each semen sample, there are millions of sperm and varying amounts of other substances that support fertilisation.A typical semen analysis could measures:Volume of semenConsistency (thickness) of the semenSperm concentrationTotal number of spermSperm motility (the percentage that are able to move, as well as how vigorously and progressively the sperm move)Number of normal and not normal (defective) spermCoagulation and liquefactionFructose (a sugar in semen)pH (acidity)Number of immature spermNumber of white blood cells (cells that indicate infection)Additional tests may be performed if semen is abnormal, such as a test for antisperm antibodies. If assisted reproductive technology is contemplated, example.g. in vitro fertilisation (IVF), sperm function tests may also be performed.


Test Name:
Serum Cortisol, Urine Cortisol, Urinary Free Cortisol, Salivary Cortisol


Test Name:
Serum Protein Electrophoresis , Urine Protein Electrophoresis , IFE


Test Name:
Serum protein electrophoresis and urine protein electrophoresis


Other Names:
sTfR; Transferrin Receptor; TfR; Serum Transferrin Receptors

Related Tests:
Iron Tests, Iron, Ferritin, TIBC & UIBC, Transferrin, Zinc Protoporphyrin, FBC, Haemoglobin, Haematocrit

Why:
detect iron deficiency anaemia and distinguish it from anaemia caused by chronic illness or inflammation

Sample Type:
blood sample drawn from a vein in your arm

Test General info:
Soluble transferrin receptors (sTfR) are proteins found in blood that can become elevated in the presence of iron-deficiency. This test measures the amount of soluble transferrin receptors within the blood, to help detect and evaluate iron deficiency and aid in the diagnosis of iron deficiency anaemia.Iron is an essential nutrient absorbed from the diet. Transferrin is the main protein in the blood that binds to iron and carries it to tissues and cells throughout the body. About 80% of iron is transported to the bone marrow, where it is incorporated into the haemoglobin in red blood cells (RBCs), and the rest is stored in other cells and tissues as ferritin and haemosiderin.When transferrin binds to iron, they form a complex. These complexes bind to transferrin receptors found on the surface of cells and the iron is then transported into the cells. Transferrin receptors are cleaved from the surface of cells, enter the bloodstream, and become soluble transferrin receptors (sTfR).The number of transferrin receptors found on the surface of cells correlates with the concentration of iron within cells. When the iron level drops, the cells produce more transferrin receptors. As more receptors are produced, more are cleaved from cell surfaces and enter the blood, increasing the concentration of soluble transferrin receptors. Thus, measuring the amount of sTfR’s within the bloodstream is one way of evaluating the amount of iron available in the body.Red blood cells have a lifespan of about 120 days. Because of this, the bone marrow must continually produce new RBCs. If there is insufficient iron taken in through the diet and/or increased iron loss (e.g., bleeding), iron reserve stored in the body is decreased. Over time, this can lead to iron deficiency, as the amount of iron stored within the body becomes exhausted and the demand for iron exceeds the supply. As a result, fewer RBCs are produced and those newly formed RBCs are also smaller (microcytic) and contain less haemoglobin (hypochromic). This is a condition called iron deficiency anaemia.Usually, a ferritin blood test is used to evaluate the amount of iron reserve in the body and to help diagnose iron-deficiency anaemia. However, the concentration of ferritin within the blood can be elevated when an individual has inflammation or a chronic disease, such as autoimmune disorders or some cancers. In these conditions, the ferritin test is not useful and a test for soluble transferrin receptors may be requested by your doctor.


Related Tests:
Testosterone; Free Testosterone; Bioavailable Testosterone

Why:
evaluate whether the concentration of SHBG is affecting the amount of testosterone available to the body’s tissues.

When:
en your total testosterone results do not fit well with clinical signs and suggest deficient or excessive testosterone production.

Test General info:
The Sex Hormone Binding Globulin (SHBG) test measures the level of SHBG in the blood. SHBG is a protein that is produced by the liver. SHBG binds tightly to the hormones testosterone, dihydrotestosterone (DHT), and oestradiol (an oestrogen) and transports them in the blood in an inactive form. The amount of SHBG in the circulation is affected by age and sex, by decreased or increased testosterone or oestrogen production.  It is also affected by certain diseases and conditions such as liver disease, hyperthyroidism or hypothyroidism, by obesity, and by anticonvulsant drugs like phenytoin and phenobarbitone. 

Changes in SHBG levels can affect the amount of testosterone that is available to be used by the body. Normally, about 45% of testosterone in men and about 70% in women, is tightly bound to SHBG, and most of the rest is weakly and reversibly bound to another protein, albumin. Only about 1-3% is not bound and immediately available to the tissues as free testosterone. 

A total testosterone test does not distinguish between bound and free testosterone; it measures the overall quantity of testosterone. In many cases, this measurement is sufficient to discover excessive or deficient testosterone production; but, if a patient’s SHBG level is not normal, then the total testosterone may be misleading.


Why:
monitor progression or recurrence of a rare cancer called mesothelioma; this cancer affects the membranes that surround the lungs, heart, and abdominal cavity. Most cases of mesothelioma are associated with asbestos exposure.

When:
ter you have been diagnosed with mesothelioma, this test may be requested to follow response to treatment at anytime during or after treatment.

Test General info:
This test measures the quantity in the blood of a small molecule called mesothelin-related peptides (SMRP). These peptides are breakdown products from proteins found in the membranes lining the cavities that surround the lungs, heart, and abdomen. Large amounts of SMRP are often seen in the blood of patients suffering from mesothelioma, and the amount of SMRP in the blood is thought to be related to the extent of the disease. Malignant mesothelioma is a rare cancer of the membranes that cover the outside of internal organs and line body cavities, including the chest (pleural mesothelioma), abdominal cavity (peritoneal mesothelioma), and the heart (pericardial mesothelioma). Pleural mesothelioma is the most common type, accounting for 90% of all cases. Most cases of pleural mesothelioma-about 70% to 80%-arise in patients with a history of working with asbestos, especially in the shipbuilding, construction, automotive, and fireproofing industries. The disease has a long latency period, meaning that patients usually develop mesothelioma 20 to 50 years after asbestos exposure.


Other Names:
Sometimes referred to by brand name (e.g. Vancocin)

Related Tests:
Therapeutic Drug Monitoring; Urea; Creatinine; C.diff (Clostridium difficile toxin); MRSA Screening

Why:
measure and monitor the concentration of vancomycin in the blood

Test General info:
This test measures the concentration of vancomycin in the blood. Vancomycin is an antimicrobial that is used to treat serious infections caused by gram-positive bacteria. Developed in the 1950s, vancomycin was originally prescribed primarily when organisms proved resistant to penicillin or when a person was allergic to penicillin. Its use declined with the introduction of other antimicrobials such as meticillin, but has risen again with the emergence of meticillin-resistant strains of staphylococcus, such as staphylococcus aureus (Meticillin Resistant Staphylococcus Aureus, MRSA).Intravenous vancomycin may be given to treat infections such as septicaemia (infection of the blood), endocarditis (infection of the membrane surrounding the heart), osteomyelitis (infection of the bone), some pneumonias, and meningitis (infection of the spinal cord).  It is often the drug of choice for meticillin-resistant staphylococcus epidermidis and staphylococcus aureus infections, especially when they are associated with implanted devices such as heart valves, artificial hips, and indwelling catheters.  Vancomycin may also be given to prevent an infection (prophylactically) to some people before specific surgeries and dental procedures.  Intravenous vancomycin administration is necessary to get drug into the circulation because oral vancomycin is poorly absorbed through the intestine.   Oral vancomycin is prescribed to treat some resistant clostridium difficile infections, which occur in the gastrointestinal tract where absorption into the circulation is not needed.  The effectiveness of vancomycin depends on maintaining blood levels at a minimum concentration for the duration of therapy.  Excessive concentrations of vancomycin must be avoided because high levels can result in damage to some organs, specifically ototoxicity (damage to hearing) and nephrotoxicity (kidney damage).  The amount of vancomycin given in each dose depends on a variety of factors, including how well the kidney is functioning, the presence of other drugs which might have casue kidney damage and the patient’s age and weight.  A patient with decreased kidney function may not be able to remove all of the drug from their system which will cause an increased concentration in the blood.  If a patient is given too little drug and is unable to maintain a sufficient minimum dose in the blood, then it is unlikely that treatment will be effective.  The vancomycin test can be used to monitor the amount of drug in the blood to ensure that it is adequate but not excessive.


Why:
determine whether you have pathogenic bacteria in your gastrointestinal tract.

When:
en you have diarrhoea that lasts more than a few days and/or have blood or mucous in your loose stools.

Test General info:
The stool culture is a test that allows the detection and identification of pathogenic bacteria in the stool. In the laboratory, a small amount of a fresh faecal sample is applied to a variety of nutrient media (thin layers of gelatin like material in sterile covered plastic dishes). These media are selective, each encourages the growth of some bacteria and discourages the growth of others. Once inoculated, the media are incubated and checked daily for bacterial growth. Bacteria that are present in the stool grow as colonies that look like dots on the surface of the gel. The physical characteristics of the colonies - their shape, colour, and some of their chemical properties are unique to each type of bacteria and allow them to be differentiated.  The bacteria in the stool are representative of the bacteria that are present in the gastrointestinal tract and it is a far from sterile environment. Bacteria and fungi called “normal flora” inhabit the gastrointestinal tract. They play an important role in the digestion of food and they form a protective barrier against the growth of other pathogenic bacteria. Normal flora are usually in balance but sometimes one, such as Clostridium difficile, will become pathogenic by overgrowing. This upsets the balance of the normal flora and may lead to the production of toxins that can irritate and damage the intestinal tract. Bacterial overgrowth is usually a side effect of the administration of broad-spectrum antibiotics (which depresses the growth of the other normal flora) but it may also be seen in patients who are immunocompromised.Other pathogenic bacteria are usually brought into the body when someone eats food or drinks water that has been contaminated. This may include raw or undercooked eggs, poultry or beef, unpasteurized milk, and contaminated water from lakes, streams, and (occasionally) from community water supplies. Those that travel outside the U.S., especially to developing nations, may face a greater risk of being exposed to a pathogenic bacteria. Some of these bacteria may be “true pathogens” while others are strains of gastrointestinal bacteria that are normal flora for the locals, but cause gastrointestinal distress to the tourist. Visitors may become infected by eating or drinking anything that has been contaminated with the bacteria (things as simple as tap water, ice cubes in a drink, a fresh salad, or food from a vendor’s stall).The most common symptoms of a pathogenic bacterial infection are prolonged diarrhoea, bloody diarrhoea, mucous in stool, abdominal pain, and nausea. If diarrhoea lasts more than a few days, it may lead to dehydration and electrolyte imbalance - dangerous conditions in children and the elderly. Dehydration can cause symptoms such as: thirst, dry skin, fatigue, light-headedness, and fever. Severely affected patients may require hospitalization to replace lost fluids and replace lost electrolytes. A serious complication that may occasionally arise is haemolytic uraemic syndrome. It is most frequently seen in children infected with Eschericia coli 0157:H7 and may lead to the destruction of red blood cells and to kidney failure.The most common pathogenic bacteria and their most frequently encountered sources include: Salmonella, often found in raw eggs (even intact disinfected eggs), raw poultry and in reptiles. Pets, such as lizards and turtles, may carry salmonella in their intestines without being ill themselves. Some humans may become carriers of salmonella. Shigella, from faecally contaminated food and water, and from infected-person to person when careful sanitation is not observed. For instance, it can be a challenge to prevent the spread of shigella within a family, and in a day care or nursing home setting. Campylobacter, from raw or undercooked poultry. It is the most common cause of bacterial diarrhoea in the U.S. It may become especially serious if it spreads to the bloodstream and occasionally causes long-term complications such as arthritis, and Guillain-Barré syndrome (an autoimmune condition affecting the nervous system). Escherichia coli 0157:H7 (other strains of E. coli are normal flora). Found in raw or undercooked hamburger / beef or unpasteurized cider. Causes bloody diarrhoea and may lead to haemolytic uraemic syndrome. Others include: Staphylococcus aureus, Clostridium difficile and strains of Yersinia and Vibrio.


Other Names:
T-cell Gene Clonality; TCGR; TCR Gene Rearrangement

Related Tests:
Full Blood Count, White Blood Cell Differential, Blood Film, Immunophenotyping, Chromosome Analysis, Bone Marrow Aspiration and Biopsy, B-cell Immunoglobulin Gene Rearrangement

Why:
help diagnose a T-cell lymphoma; sometimes to detect and evaluate residual cancer cells

When:
en a doctor thinks that you may have a T-cell lymphoma; when a doctor would like to assess whether treatment has been effective and/or whether lymphoma has recurred

Sample Type:
bone marrow, tissue such as a lymph node (biopsy), or body fluid sample collected by your doctor; sometimes a blood sample drawn from a vein in your arm

Test General info:
This test detects characteristic changes (rearrangements) in specific genes in T-cells. This information can be helpful in diagnosing a T-cell lymphoma.T-cells are a type of lymphocyte (a kind of white blood cell, WBC) that helps to protect the body from infection. Rearrangements in certain parts of their DNA called receptor genes are a normal part of their development. These rearrangements are associated with the development of a large repertoire of diverse T-cells, allowing them to protect against many different kinds of infections. The final order in which the genes are rearranged is called a gene rearrangement profile. Within any normal population (sample) of T-cells, the cells and their gene rearrangement profiles are very diverse.In lymphoma, the T-cells in affected tissue (such as blood, lymph node, or skin) are identical and their gene rearrangement profiles are likewise identical. Lymphomas arise when an abnormal T-cell begins to produce numerous identical copies of itself (clones). The cloned cells grow and divide uncontrollably, crowding out normal cells.A T-cell receptor gene rearrangement test evaluates the T-cells in a person`s sample to determine whether the majority of T-cell rearrangement profiles are diverse or identical. This information, along with clinical signs and symptoms and results of other laboratory tests, can help clarify a person`s diagnosis, or evaluate for persistent or recurrent lymphoma.B-cell lymphomas are far more common than T-cell lymphomas. There are many different types of T-cell lymphomas, but each is rare.For additional details about T-cells and this testing, read more.


Related Tests:
Free (FT) and bioavailable testosterone; Follicle stimulating hormone (FSH); luteinising hormone (LH); sex-homone-binding globulin (SHBG); oestradiol (E2), androstenedione; dehydroepiandrosterone sulphate (DHEAS)

Why:
find out if testosterone levels are abnormal in a male or female patient. Measurement may help to explain why a man has difficulty in getting an erect penis (erectile dysfunction), the inability of your partner to get pregnant (infertility), premature or

When:
you are man and your doctor thinks that you may be infertile or if you are unable to get or maintain an erectionIf you are a boy with either early or delayed sexual maturityIf you are a female but have male traits, such as a low voice or excessive body hair (hirsutism), or are infertile or have no periods or if they are irregular

Test General info:
Testosterone is a steroid hormone (androgen) made by the testes in males. The production of testosterone is stimulated and controlled by luteinising hormone (LH), which is manufactured in the pituitary gland.In men, testosterone stimulates the enlargement of the penis, growth of body hair, muscle development, and a deepening voice. It is present in large amounts in boys during puberty and in men to regulate the sex drive and maintain muscle mass.In women testosterone levels are about one tenth of those in men.  Testosterone is produced both in small amounts from the ovary and by conversion from other weak androgens in the body.Testosterone is also produced by the adrenal glands in both men and women.


Related Tests:
TSH, total T4, total T3, free T4, free T3, Thyroid Antibodies, Calcitonin, Thyroglobulin

Why:
help evaluate thyroid gland function, to help diagnose thyroid disorders and to monitor the response to treatment.

When:
part of a health checkup or when symptoms suggest hypo- or hyperthyroidism due to a condition affecting the thyroid; following commencement of treatment for disorders of the thyroid gland.

Test General info:
Thyroid function tests (TFTs) are a group of tests that are requested together to help evaluate thyroid gland function, to help diagnose thyroid gland disorders and to monitor the response to treatment of thyroid disorders. TFTs include a measure of the amount of thyroid hormones, Thyroxine (T4) or Tri-iodothyronine (T3) in your blood. These hormones are chemical substances that travel through the bloodstream and control or regulate your body’s metabolism—how it functions and uses energy. Thyroid hormones are present in the blood in either protein bound forms (the majority) or the free and active form of the hormone. Currently, the majority of UK laboratories measure the free form of the hormones – Free T4 (FT4) or Free T3 (FT3).Thyroid Stimulating Hormone (TSH) is produced by the pituitary gland and is part of the body’s feedback system to maintain stable amounts of thyroid hormones in the blood. When thyroid hormone concentrations decrease in the blood, the pituitary gland is stimulated to release TSH, which in turn stimulates the production and release of T4 and T3 by the thyroid gland. When the system is functioning normally, TSH production turns on and off to maintain constant blood thyroid hormone concentrations.Thyroid Function Tests usually include some combination of:TSH (thyroid stimulating hormone or thyrotropin)– to test for hypothyroidism, hyperthyroidism and to monitor thyroid replacement therapyT4 or FT4– to test for hypothyroidism and hyperthyroidismT3 or FT3– to test for hyperthyroidism


Related Tests:
Cholesterol; Non-HDL; HDL; LDL; Lipid profile; Cardiac risk assessment

Why:
part of a full lipid profile to assess the risk of developing cardiovascular disease, or to look for an underlying cause for a condition called pancreatitis

When:
part of a lipid profile during a medical examination, after a diagnosis of pancreatitis, or if you are being treated for high triglycerides

Test General info:
This test measures the amount of triglycerides in your blood. Triglycerides are the body`s storage form of fat. Most triglycerides are found in fat (adipose) tissue, but some circulate in the blood to provide fuel for muscles to work. Extra triglycerides are found in the blood after eating a meal — when fat is being sent from the gut to fat tissue for storage.


Why:
e detection of patients who are at risk of developing severe side effects if treated with the thiopurine drugs, azathioprine, mercaptopurine and thioguanine

Sample Type:
single blood sample taken from a vein in your arm

Test General info:
Thiopurine drugs suppress the immune system and are used to treat patients after organ transplants and in the treatment of a wide range of diseases such as leukaemia, inflammatory bowel disease and skin disorders such as eczema. The most commonly used thiopurine drug is called azathioprine.
1 person in every 300 lacks thiopurine s-methyltransferase (TPMT) which is an enzyme which helps remove thiopurine drugs such as azathioprine from the body. Individuals with no TPMT enzyme can become severely ill if treated with normal doses of thiopurine drugs. These patients develop bone marrow suppression with a reduction in blood cells, which causes anaemia, infection and abnormal bleeding. Such side effects can be avoided if TPMT is measured before starting treatment.


Related Tests:
Thyroglobulin antibody; Tumour markers; TSH; Thyroxine (T4)

Why:
monitor treatment of some types of thyroid cancer and to look for return of the cancer

When:
ce treatment for thyroid cancer has been completed, before and after radioactive iodine therapy for thyroid cancer, and at varying intervals to monitor for recurrence.

Test General info:
The thyroid gland is a small butterfly shaped organ that helps to regulate the rate at which the body uses energy. The thyroid lies flat against the windpipe in the throat and is composed primarily of very small, ball-shaped structures called follicles. This test measures the amount of thyroglobulin in the blood. Thyroglobulin is a protein produced by follicle cells and stored in the thyroid gland. Thyroglobulin is broken down when needed into the thyroid hormones T4 (thyroxine) and T3 (triidothyronine). The production of these hormones and their release into the blood stream is stimulated by the hormone TSH (thyroid stimulating hormone). No other part of the body makes thyroglobulin, but it is produced by many thyroid cancers – both those confined to the thyroid gland and those that have spread to other parts of the body.


Test Name:
Thyroid stimulating hormone receptor antibody


Why:
screen for and diagnose thyroid disorders; to monitor treatment of hypothyroidism and hyperthyroidism

When:
r screening: All newborns are screened for congenital hypothyroidism. There is currently no recommendation in the UK for routine screening of adults
For monitoring treatment: as directed by your doctor
Otherwise: when a patient has symptoms of hypo- or hyperthyroidism and/or an enlarged thyroid

Sample Type:
blood sample taken from a vein in the arm. For neonatal screening blood is collected by pricking the heel

Test General info:
The test measures the amount of thyroid-stimulating hormone (TSH) in your blood, which is an indicator of thyroid disease. TSH is made by the pituitary gland, a tiny organ located below the brain and behind the sinus cavities. It is part of the body’s feedback system to maintain stable amounts of the thyroid hormones thyroxine (T4) and triiodothyronine (T3) in the blood.

Thyroid hormones help control the rate at which the body uses energy. When concentrations decrease in the blood, the hypothalamus (an organ in the brain) releases thyrotropin releasing hormone (TRH). This stimulates the release of TSH by the pituitary gland. The TSH in turn stimulates the production and release of T4 and T3 by the thyroid gland, a small butterfly-shaped gland that lies in the neck flat against the windpipe. When all three organs are functioning normally, thyroid hormone concentrations in the blood remain constant.


Other Names:
total iron-binding capacity; total iron saturation; transferrin saturation; unsaturated iron-binding capacity

Related Tests:
Iron Tests, Serum Iron, Ferritin, Zinc Protoporphyrin, Full Blood Count, Haemoglobin, Haematocrit, Reticulocyte Count, Soluble Transferrin Receptor

When:
en your doctor suspects you may have too much or too little iron in your body because of a variety of conditions

Test General info:
Total Iron Binding Capacity, or TIBC, measures the total capacity of your blood to bind and transport iron, and therefore reflects your body`s iron stores. TIBC correlates with the amount of the protein transferrin in your blood, available to bind iron. Transferrin is a protein that attaches iron molecules and transports iron in the blood plasma. Transferrin is largely made in the liver and regulates your body’s iron absorption into the blood. While the two tests (TIBC and transferrin) are different, they measure essentially the same thing and most laboratories only measure one or the other. A few laboratories are now measuring the number of sites on transferrin that are not already carrying iron; this is referred to as unsaturated iron binding capacity (UIBC). This number can be added to the serum iron to calculate the TIBC.


Why:
screen for several infectious diseases that can cause birth defects in newborns and illness in adults

When:
you become ill while pregnant or if a baby is born with congenital abnormalities that may be caused by an infection with one of these diseases

Sample Type:
blood sample is taken from a vein in the arm by needle or by heel prick for infants

Test General info:
TORCH is an acronym for a group of four infectious diseases that may cause illness in pregnant women and may cause birth defects in their newborns. The test is a screen for the presence of any of the antibodies to these infections. Confirmation of an active infection may require more specific tests. 

The following tests make up the TORCH panel:Toxoplasmosis is a parasitic infection that can be passed from mother to baby through the placenta during pregnancy. An infection with Toxoplasma gondii can cause eye and central nervous system infections as well as brain and muscle cysts. If acquired during the pregnancy, it may result in a miscarriage or cause birth defects, though this depends on the time during the pregnancy in which the infection was acquired by the mother. Toxoplasmosis is acquired by ingesting the parasite when handling the excrement of infected cats, drinking unpasteurized goat’s milk, and, most commonly, by eating contaminated meat. Rubella is the virus that causes German measles. If contracted early in the pregnancy, the infant may develop heart disease, retarded growth, hearing loss, blood disorders, vision problems, or pneumonia. Problems that may develop during childhood include autism, brain problems, immune disorders, or thyroid disease. Cytomegalovirus (CMV) is another viral infection that the mother may have acquired. More than half of all American adults have been infected with CMV at some point in their life and, in most cases, it does not cause severe illness. It may pass to the foetus during pregnancy but can also infect newborns through breast milk. Most infected babies do not show any signs of infection at birth. Infected infants may have severe problems, such as hearing loss, mental retardation, pneumonia, hepatitis, or blood disorders. Herpes simplex virus (HSV) is a common viral infection. The two most common infections with HSV are “cold sores” affecting the lips and genital herpes. Both of these infections can recur. HSV is most commonly acquired through oral or genital contact. Newborns who contract the virus usually do so during travel through the birth canal of a woman who has a genital infection with HSV. The virus may spread throughout the newborn’s body, attacking vital organs. Treatment with specific antiviral medication should begin as soon as possible in the infected newborn. Even if treated, surviving babies may have permanent damage to the central nervous system. Mothers with recent or active genital herpes symptoms at the time of birth should inform the delivery staff.


Test Name:
Total bilirubin, conjugated or direct bilirubin, unconjugated or indirect bilirubin


Why:
diagnose an infection with Trichomonas vaginalis

When:
you have symptoms of infection, including vaginal discharge or pain during urination

Test General info:
The test is looking for infection by Trichomonas vaginalis, a sexually transmitted, microscopic parasite that causes vaginal infections in women and urethritis in some men.


Related Tests:
Synovial Fluid Analysis, Kidney Stone Analysis

Why:
detect high levels of uric acid, which could be a sign of the condition gout, or to monitor uric acid levels when undergoing chemotherapy or radiotherapy; to detect high levels of uric acid in the urine in order to diagnose the cause of kidney stones and

When:
en you have joint pain or other symptoms that your doctor suspects may be due to gout; when monitoring certain chemotherapy or radiation therapies for cancer; when you have recurrent kidney stones; when you have gout or are otherwise at risk for kidney stone formation

Sample Type:
blood sample taken from a vein in the arm or a 24-hour urine sample

Test General info:
Uric acid is produced by the breakdown of purines, which are nitrogen-containing compounds found in the body in substances such as nucleic acids (DNA, RNA).  They enter the circulation from digestion of certain foods, drinks (alcoholic beverages like beer and wine) or from normal breakdown and turnover of cells in the body.  Most uric acid is removed by the kidneys and disposed of in the urine; the remainder is excreted in the stools.If too much uric acid is produced or not enough is excreted, it can accumulate in the body and cause increased levels in the blood (hyperuricemia).  The presence of excess uric acid can cause the condition called gout – an inflammation that occurs in joints when crystals derived from uric acid form in the joint fluid.  Excess uric acid can also lead to kidney disease, as a result of deposition in the kidneys or kidney stone formation, as a result of increased urinary excretion.The accumulation of too much uric acid is due to either increased production, decreased elimination or a combination of both. Increased production can be caused by, for example, increased cell death, as may be seen with some cancer treatments, or, rarely, may be due to an inherited tendency to overproduce uric acid. Decreased elimination of uric acid is often a result of impaired kidney function due to kidney disease. In many cases, the exact cause of excess uric acid is unknown. Doctors seldom need to test for low levels of uric acid.Uric acid levels are also increased in pre-eclampsia and may be measured as part of the assessment of this condition.


Related Tests:
Urine culture; Urine protein; Urea; Creatinine; Creatinine clearance; Microalbumin; eGFR

Why:
look for metabolic and kidney disorders and for urinary tract infections

When:
admission to a hospital; preparation for surgery; as part of a medical examination; or when evaluating a new pregnancy. It may be done if you have tummy or back pain, frequent or painful urination, or blood in the urine

Test General info:
This test identifies and measures some of the by-products of normal and abnormal metabolism, cells, cell fragments, and bacteria in urine. Urine is produced by the kidneys, which filter wastes out of the blood, help regulate the amount of water in the body, and conserve proteins, electrolytes, and other compounds that the body can reuse. Anything that is not needed is excreted in the urine.

Several diseases can be diagnosed in their early stages by detecting abnormalities in the urine. Abnormally high levels of glucose, protein, bilirubin, red blood cells, white blood cells, crystals, and bacteria can indicate disease. They may be present because: 1) There are elevated concentrations in the blood which spill over into urine, 2) Kidney disease has made the kidneys less effective at filtering or, 3) An infection has put bacteria and white blood cells into the urine .A complete urinalysis consists of three distinct testing phases:Visual examination, which evaluates the urine`s colour, clarity, and concentration; Chemical examination, which tests chemically for a number of substances that provide valuable information about health and disease; and Microscopic examination, which identifies and counts the type of cells, casts, crystals, and other components (bacteria, mucous ) that can be present in urine. Today, a routine urinalysis consists of the visual and the chemical examinations. Your urine may be examined under a microscope if there is an abnormal finding in one of the first two phases listed above or if your doctor specifically requests it.


Test Name:
Urine Albumin to Creatinine Ratio or ACR


Test Name:
Urine Protein and Urine Protein to Creatinine Ratio


Related Tests:
Catecholamines; Plasma Free Metadrenalines; Urine Metadrenalines; Homovanillic Acid; Urine Creatinine

Why:
help diagnose or rule out a neuroblastoma, phaeochromocytoma, or other neuroendocrine tumour; to monitor the effectiveness of treatment

When:
en your child has an abdominal mass, bruising around the eyes, trouble walking, or bone pain; when you have symptoms of increased catecholamine release, such as persistent or episodic high blood pressure, severe headaches, rapid heart rate, and sweating; when you have been treated for a neuroendocrine tumour, such as neuroblastoma or phaeochromocytoma

Sample Type:
24-hour urine sample is preferred; sometimes a random urine sample is acceptable.

Test General info:
Vanillylmandelic acid (VMA) is one of the metabolites of the catecholamines adrenaline (epinephrine) and noradrenaline (norepinephrine). This test measures the amount of VMA that is excreted into the urine, typically over a 24-hour period, to detect excess catecholamine production.Catecholamines are a group of similar hormones produced in the central portion of the adrenal glands, the adrenal medulla. Adrenal glands are small triangular organs located on top of each kidney. The primary catecholamines that they release are dopamine, adrenaline, and noradrenaline. These hormones are released into the bloodstream in response to physical or emotional stress. They help transmit nerve impulses in the brain, increase glucose and fatty acid release for energy, dilate bronchioles, and dilate the pupils. Noradrenaline also constricts blood vessels, increasing blood pressure, and adrenaline increases heart rate and metabolism. After completing their actions, the catecholamines are metabolised to inactive compounds. Dopamine becomes 3-methoxytyramine (3-MT) and homovanillic acid (HVA), noradrenaline breaks down into normetadrenaline and VMA, and adrenaline becomes metadrenaline and VMA. Both the hormones and their metabolites are excreted in the urine.VMA is usually present in the urine in small fluctuating amounts that only increase appreciably during and shortly after the body is exposed to stress. Neuroblastomas, phaeochromocytomas, and other neuroendocrine tumours, however, can produce large amounts of catecholamines, resulting in greatly increased concentrations of the hormones and their metabolites. The hormone releases can cause persistent hypertension, severe headaches, palpitations, sweating, nausea, anxiety, and tingling in the extremities.Neuroblastomas are the most common extra cranial solid tumour in childhood and most frequently diagnosed during infancy. The incidence of neuroblastoma is 10.2 cases per million children under 15 years of age. Up to 90 per cent of cases occur in children under the age of five. Rarely, a baby may be born with a neuroblastoma. Arising from primitive nerve cells, the cancers can be found in the abdomen (~65 per cent of primary tumours), adrenal glands, neck, chest, or pelvis. About two-thirds of the time, the tumours will have metastasised and moved to other parts of the body by the time they are diagnosed. Once detected, many neuroblastomas can be successfully treated. In some cases, neuroblastomas may disappear on their own or their cells may spontaneously mature into normal nerves cells, turning the neuroblastoma into a benign ganglioneuroma or into a partially benign ganglioneuroblastoma.Phaeochromocytomas are rare tumours that arise primarily in the adrenal glands. According to the National Cancer Institute, they affect 2 to 5 people per million per year, primarily those in their thirties to fifties. Most phaeochromocytomas are benign and do not spread from their original location (~85 per cent), but some may metastasise and move to other organs within the body. Left untreated, they continue to grow and produce catecholamines, and hormone-related symptoms continue to worsen. Over time, the hypertension that the phaeochromocytoma causes may damage body organs, such as the kidneys and heart, and raise the risk of an affected person having a stroke or heart attack. Phaeochromocytomas are important to diagnose because they represent a potentially curable form of hypertension. In most cases, they can be removed and/or treated to reduce or eliminate the associated symptoms and complications.The VMA test, along with other tests for catecholamines and their metabolites, can be used to help detect the presence of neuroblastomas and phaeochromocytomas.


When:
en other tests are being done to assess vascular risk

Test General info:
Very low density lipoprotein is one of the three major lipoprotein particles. The other two are high density lipoprotein (HDL) and low density lipoprotein (LDL). Each particle contains a mixture of cholesterol, triglyceride and protein, but in varying amounts unique to each type of particle. VLDL contains the highest amount of triglyceride and is called a triglyceride rich lipoprotein. VLDL particles are released into the blood by the liver and circulate in the bloodstream, ultimately being converted into LDL as they lose triglyceride having carried it to other parts of the body.At present there is no simple direct way of measuring cholesterol in VLDL and so it is estimated from triglyceride which is mainly present in VLDL. The calculation used is not valid when the triglyceride level is greater than 4.5 mmol/L.

The VLDL cholesterol concentration can be measured directly using a technique called ultracentrifugation. However, this technique is not straightforward and not usually done in clinical laboratories. This test is generally carried out in specialist laboratories, most often for research purposes.


Why:
determine the cause of viral meningitis or encephalitis that occurs during the summer season; to detect the presence of West Nile Virus (WNV)

When:
en a patient has symptoms suggesting WNV such as headache, fever, stiff neck, and muscular weakness and a diagnosis of encephalitis and/or meningitis; also used as a screen for WNV in donated units of blood

Test General info:
West Nile virus (WNV) is an infection that is transmitted to humans primarily by mosquitoes. It is not usually transmitted person-to-person, but there have been cases of WNV being passed on to others through blood donations, organ transplants, and rarely from a mother to child through breast milk. About 80% of the people infected with WNV experience no symptoms. In the other 20%, it causes flu-like symptoms such as headache, fever, nausea, muscular weakness, and/or a skin rash on the back or chest. These symptoms usually resolve without treatment within a few days to a few weeks. Only about 1 in 150 people infected with WNV becomes seriously ill with an infection that affects the central nervous system. These patients frequently experience severe symptoms such as confusion, convulsions, high fever, neck stiffness, headaches, or a coma. They may have encephalitis and/or meningitis and/or may experience muscular paralysis. This serious form of WNV is much more common in the elderly and in the immunocompromised. While most symptoms resolve within several weeks, some nerve damage and paralysis may linger or be permanent.


# test_infor21

Other Names:
Anti-beta-2 glycoprotein 1; β2-glycoprotein 1 antibodies; Beta 2GP1 Ab

Formal Name:
Beta-2 glycoprotein 1 antibodies (IgG, IgM, and very rarely IgA)

Related Tests:
Cardiolipin antibodies, lupus anticoagulant, antiphospholipid antibodies, anti-phosphatidylserine antibodies, anti-prothrombin antibodies

Why:
To help investigate inappropriate blood clot formation; to help determine the cause of recurrent miscarriage; as part of an evaluation for antiphospholipid syndrome (APS)

When:
When you have had one or more unexplained blood clots in a vein or artery; when you have had recurrent miscarriages, especially in the second and third trimesters

Sample Type:
A blood sample taken from a vein in your arm

Test Prep:
No test preparation is necessary.
The Test

Test General info:
This test detects and measures one or more classes (IgG, IgM, or very rarely IgA) of beta-2 glycoprotein 1 antibodies. Beta-2 glycoprotein 1 antibody is one of three primary antiphospholipid antibodies, which are autoantibodies (produced by the body and a

Related Diseases:
Conditions: Antiphospholipid Syndrome, Autoimmune Disorders, Excessive Clotting Disorders


Other Names:
Ergocalciferol (vitamin D2); Cholecalciferol (vitamin D3); Calcidiol (25-hydroxyvitamin D [25(OH)D]); Calcifidiol (25-hydroxy-vitamin D); Calcitriol (1,25 dihydroxyvitamin D [1,25(OH)(2)D])

Formal Name:
25-hydroxy-vitamin D (Calcidiol); 1,25 dihydroxy-vitamin D (Calcitriol)

Related Tests:
Calcium; Phosphate; Parathyroid Hormone (PTH); Magnesium; Bone Markers; Trace Elements

Why:
To investigate a problem related to bone metabolism or parathyroid function, possible vitamin D deficiency, malabsorption and to monitor some patients taking vitamin D.

When:
Your doctor may request a vitamin D measurement in the following situations:
If you are found to have an abnormal calcium, phosphate, and/or parathyroid hormone (PTH) concentration in the blood. 
As part of the investigation of some forms of bone disease or muscle weakness/pain. 
If you have disease of the gastrointestinal tract that could result in malabsorption. 
If you are receiving certain anticonvulsant drugs.

Test General info:
The main role of vitamin D is to help regulate the absorption of calcium, phosphate, and (to a lesser extent) magnesium from the gut. Vitamin D is vital for the growth and health of bone; without it, bones will be soft, malformed, and unable to repair the

Related Diseases:
Conditions: Kidney disease, lymphoma, autoimmune conditions, cystic fibrosis, coeliac disease


Why:
To help diagnose a serotonin-secreting carcinoid tumour

When:
When you have symptoms suggestive of a carcinoid tumour such as flushing, diarrhoea and/or wheezing

Test General info:
This test measures the amount of serotonin in the blood. Serotonin is a chemical derived from the amino acid tryptophan. It is produced as needed by the nervous system, mainly the brain, but also by special cells in the bronchial tubes (lungs) and gastroi

Related Diseases:
Apart from the Related Tests noted above, there are no other related pages on this site.


Other Names:
5-hydroxyindoleacetic acid; HIAA; Serotonin metabolite

Why:
To help diagnose and monitor treatment for a serotonin-secreting carcinoid tumour

When:
When you have symptoms suggestive of a carcinoid tumours such as flushing, diarrhoea, and/or wheezing and at intervals following treatment

Sample Type:
A 24-hour urine sample; rarely a random urine sample
The Test Sample

Test General info:
This test measures the amount of 5-hydroxyindoleacetic acid (5-HIAA) in the urine. 5-HIAA is a muscle stimulant and the primary metabolite of serotonin, a chemical derived from the amino acid tryptophan. Serotonin is produced as needed by the nervous syst


Other Names:
17-OHP; 17-OH progesterone; Progesterone - 17-OH

Why:
To screen for, detect, and monitor treatment for congenital adrenal hyperplasia (CAH); sometimes to help rule out other conditions

When:
1. as part of a routine newborn screen, when an infant has ambiguous genitalia i.e it unclear if the child is male or female
2. when a young female has hirsutism (excess hair) or other symptoms of virilization
3. when a male child has premature sexual development
4. periodically to monitor CAH treatment

Sample Type:
A blood sample taken from a vein in your arm or blood from a heelprick for an infant

Test Prep:
There is no preparation such as fasting for this test, but the doctor may request an early morning collection. The doctor may also request that blood be collected in the first half of a woman`s menstrual cycle.
The Test

Test General info:
This test measures the amount of 17-hydroxyprogesterone (17-OHP) in the blood. 17-OHP is a steroid which is metabolised to make cortisol; it is a substance used by the body to make cortisol. Cortisol is a hormone produced by the adrenal glands that helps

Related Diseases:
Conditions: PCOS, Adrenal Insufficiency,  Infertility
Screening: Newborns


Other Names:
24 Hour Urine Protein; Urine Total Protein; Urine Protein to Creatinine Ratio

Related Tests:
Urinalysis; Albumin; Microalbumin; Protein Electrophoresis; Total Protein

Why:
To detect excessive protein escaping into the urine, to help evaluate and monitor kidney function, and to detect kidney damage

When:
As part of a routine check-up, as a follow-up to a previous positive urine protein test, or if you have a disorder or disease that frequently affects the kidney

Sample Type:
A random or 24-hour urine sample; occasionally a split 24-hour sample, with the night collection separated from the day collection
The Test Sample

Test General info:
The urine protein test measures the amount of protein being excreted in the urine. There are several different kinds of urine protein tests. A semi-quantitative protein “dipstick” is frequently performed as part of a urinalysis, generally on a random urin


Related Tests:
Protein electrophoresis, Total protein, Blood gases, Liver function tests

Why:
To help diagnose the cause of early onset emphysema and/or liver disease. To establish the risk of developing alpha-1 antitrypsin-related emphysema and/or liver disease and the likelihood that children might inherit the risk

When:
When you show signs of liver disease as an infant or young child, when you develop emphysema (a disease that damages the lungs) before age 40, or when you have a close relative with alpha-1 antitrypsin deficiency

Sample Type:
A blood sample taken from a vein in your arm
The Test Sample

Test General info:
Alpha-1 antitrypsin (A1AT) is a protein that is produced in the liver and released into the bloodstream. A1AT works by inactivating several enzymes but the main one is the enzyme elastase present in the lungs. Elastase is an enzyme produced by neutrophils

Related Diseases:
Conditions:  Liver disease, Lung diseases


Other Names:
Alloantibody Identification; Antibody ID, RBC; Ab ID

Related Tests:
Direct Antiglobulin; Indirect Antiglobulin; Blood Typing; Type and screen; Crossmatch

Why:
To identify the specific antibody present when a direct antiglobulin test (DAT) or indirect antiglobulin test (IAT) is positive; to help identify the cause of a transfusion reaction or the cause of haemolytic disease of the newborn (HDN)

When:
When an IAT screening test is positive when performed as part of a prenatal workup or prior to a blood transfusion; when a person has a positive DAT following a suspected transfusion reaction or is suspected to have an autoimmune haemolytic anaemia; when a newborn has HDN

Test General info:
Antibodies to red blood cells (RBCs) can be produced by the body`s immune system in response to being exposed to ``foreign`` RBC antigens, structures found on the surface of RBCs. This test identifies the specificity of red blood cell antibodies in the bl

Related Diseases:
Conditions: Anaemia, Pregnancy, Bleeding Disorders
Feature Articles: Blood Banking


Why:
To detect the presence of anticentromere antibodies; to help diagnose limited cutaneous scleroderma

When:
When you have one or more symptoms that suggest CREST syndrome

Test General info:
The anticentromere antibody (ACA) is an antibody (a protein produced by the immune system) that targets the body`s own tissues. ACA targets the centromere, part of the chromosomes found in the nucleus of the body`s cells. The ACA is one of several autoant


Other Names:
SACE (Serum Angiotensin Converting Enzyme)

Related Tests:
AFB culture; Liver function tests; Full blood count; Calcium

Why:
To help diagnose and monitor sarcoidosis and to help distinguish it from other diseases which show similar symptoms

When:
When you have granulomas (masses of inflammatory cells) that create small bumps under the skin, a lingering cough, red watery eyes and/or other symptoms suggestive of sarcoidosis. When you have active sarcoidosis in order to follow its progress

Test General info:
Angiotensin converting enzyme (ACE) is an enzyme which helps regulate blood pressure. It converts angiotensin I (an inactive protein) to angiotensin II which causes arteries to contract, making them temporarily narrower and increasing the pressure of the

Related Diseases:
Conditions: Lung Diseases, Non-tuberculous Mycobacteria, Sarcoidosis


Related Tests:
INR (International Normalised Ratio, prothrombin time)

Why:
In order to assess risk of liver damage after overdosage and to decide on the need for protective, antidotal therapy

When:
At least 4 hours after a single overdose, or as soon as possible if more then one overdose has been taken within the last 1 or 2 days

Sample Type:
A blood sample taken from a vein usually in an arm
The Test Sample

Test General info:
The plasma paracetamol concentration is being measured.


When:
When you have symptoms associated with ketoacidosis or being monitored on a ketogenic diet.

Sample Type:
A blood sample taken from a vein in your arm or a drop of blood from your finger.

Test General info:
This test measures the amount of ketones in the blood. Ketones are produced during the bodies processing (metabolism) of fats. They are made when glucose is not available to the body’s cells as an energy source. When fatty acids are metabolised, ketones b


Other Names:
Serum ketone; Plasma ketone; Beta-hydroxybutyrate; Ketone bodies; Ketoacids; Beta-hydroxybutyric acid; Acetoacetate; Acetoacetic acid; Acetone

Related Tests:
Urine ketones; Urinalysis; Blood gases; Glucose

Why:
To determine whether excessive ketones are present in the blood, to detect diabetic ketoacidosis (DKA), to detect alcoholic ketoacidosis and to monitor ketogenic diet therapy used in the treatment of epilepsy.


Formal Name:
Acid-fast bacillus smear; culture; and sensitivity

Why:
To help identify a mycobacterial infection; to diagnose tuberculosis (TB) or to monitor the effectiveness of treatment

When:
If you have symptoms, such as a long lasting cough, weight loss, fever, chills, and weakness, that your doctor thinks may be due to TB or another mycobacterial infection. If your doctor suspects that you have active TB or wants to monitor the effectiveness of TB treatment.

Sample Type:
Usually, three specially collected spit (sputum) samples are collected early in the morning on different days. If you are unable to produce a sputum sample, a bronchoscope may be used to collect fluid during a procedure called a bronchoscopy. In children,

Test General info:
The test looks for the presence of bacteria called acid-fast bacilli (AFB) which are rod shaped bacteria that can be seen and counted under the microscope in a specially stained sample on a glass slide, called an AFB smear. The most common AFB are of a ty


Related Tests:
Albumin, Creatinine, Glucose, Haemoglobin A1c

Why:
To be screened for the early detection of kidney disease occurring as a complication of diabetes or hypertension (high blood pressure)

When:
Annually after a diagnosis of diabetes or hypertension

Test General info:
Albumin is a protein that is present in large amounts in the blood. When the kidneys are working properly, only tiny amounts of albumin pass from the bloodstream into the urine. In kidney failure (the last stage of a slow process of decline in kidney func


Related Tests:
Partial Thromboplastin Time (PTT), Prothrombin Time (PT), Anti-Xa assay

Why:
To monitor heparin and other anticoagulation when undergoing cardiopulmonary bypass, coronary angioplasty, and dialysis

When:
When you are receiving high dose heparin to prevent clotting during surgical procedures such as a cardiopulmonary bypass; when heparin levels are too high to allow monitoring with a PTT test and/or when a rapid result is necessary to monitor treatment

Test General info:
ACT is a blood clotting test that is used primarily to monitor high doses of heparin anticoagulant therapy. Heparin is a blood clot inhibitor that is usually given either intravenously (IV) or by subcutaneous (under the skin) injection. In moderate doses

Related Diseases:
Conditions: Bleeding Disorders, Hypercoagulable Disorders


Related Tests:
Cortisol; Synacthen stimulation test; dexamethasone suppression test

Why:
To diagnose adrenal and pituitary diseases such as Cushing`s syndrome, Cushing’s disease, Addison’s disease, adrenal tumours, and pituitary tumours; usually done as a diagnostic test once an abnormal cortisol level is detected

When:
If your doctor has discovered that you have abnormal cortisol levels.  ACTH will help to sort out the possible cause of the abnormal cortisol result.

Test Prep:
The sample is unstable so needs to be collected in a hospital that has laboratory facilities to process it immediately. It cannot usually be collected at a GP surgery. Typically it is taken in the morning, about 9 am.
The Test

Test General info:
Adrenocorticotropic hormone (ACTH) is a hormone produced in the pituitary gland (located below the brain within the skull) to stimulate secretion of the hormone cortisol by the adrenal glands (small organs located at the top of each kidney). Stress can st


When:
When the doctor suspects that the adrenal gland is not producing enough cortisol

Sample Type:
A blood sample is collected and then a small amount of synacthen is injected into a vein.  A further blood sample is taken after 30 minutes and sometimes after 60 minutes.
The Test Sample

Test General info:
Synacthen is a manufactured drug that acts like Adrenocorticotrophic Hormone (ACTH) by stimulating the adrenal gland to produce more cortisol. By measuring the rise in cortisol in the blood the doctor can see if the adrenal glands are secreting normal amo


Other Names:
Partial Thromboplastin Time; PTT; Kaolin Cephalin Clotting Time (KCCT)

Formal Name:
Activated Partial Thromboplastin Time (aPTT)

Related Tests:
Prothrombin Time (PT); Fibrinogen; Thrombin Time; Lupus Inhibitor; Activated Clotting Time (ACT); von Willebrand screen;Coagulation Factors; Platelet Count

Why:
As part of an investigation of a bleeding or thrombotic episode. To help evaluate your risk of excessive bleeding prior to a surgical procedure although numerous studies have shown that it cannot accurately estimate risk of bleeding in all patients. To mo

When:
When you have unexplained bleeding or thrombosis (a blood clot). When you are on unfractionated or intravenous (IV) heparin anticoagulant therapy. Sometimes as part of a pre-surgical screen

Sample Type:
A blood sample is taken by needle from a vein in the arm

Test Prep:
No test preparation is needed; however, eating a high fat meal prior to the blood test may cause interference with the test and should be avoided. It is important that the blood is collected from a medium to large calibre vein without the application of a

Test General info:
What is being tested? The activated partial thromboplastin time (aPTT or PTT) is a measure of the functionality of the intrinsic and common pathways of the coagulation cascade. The body uses the coagulation cascade to produce blood clots to seal off injur


Related Tests:
PTT, Coagulation factors, D-dimer, Fibrinogen, Homocysteine, Lupus Anticoagulant, Proteins C & S, PT, PT 20210, Factor V Leiden

Why:
To help investigate the cause of recurrent or inappropriate blood clotting; to help diagnose an antithrombin deficiency

When:
Preferably a couple of months after a thrombotic episode and not whilst taking, or for at least 6 weeks after taking anticoagulants. Occasionally testing may be requested if you are not responding as your doctor expected to heparin anticoagulation therapy

Test General info:
Antithrombin testing measures the function and quantity of antithrombin.  Antithrombin is a protein produced by the liver to help control blood clotting. Normally, when a blood vessel is injured, the body activates a series of coagulation factors, in a pr

Related Diseases:
Conditions: Hypercoagulable Disorders, Bleeding Disorders, Liver Disease


Other Names:
Hepatitis testing; Viral hepatitis testing; Hepatitis screening tests

Related Tests:
Hepatitis A; Hepatitis B; Hepatitis C; Liver function tests; AST; ALT; ALP; Bilirubin

Why:
To detect and diagnose an infection with a hepatitis virus

When:
When you have symptoms of hepatitis and a viral infection is suspected to be the cause; when you have been exposed to one or more of the three most common hepatitis viruses: Hepatitis A, B, or C

Test General info:
An acute viral hepatitis panel is a group of tests often performed together to detect a viral hepatitis infection. Hepatitis is a condition characterised by inflammation and enlargement of the liver. It has many different causes including, for example, dr

Related Diseases:
Conditions: Hepatitis, Liver Disease, Travellers` Diseases


Formal Name:
Butyrylcholinesterase; BChE; acylcholine acylhydrolase; EC 3.1.1.8

Why:
To find out if you are likely to have temporary paralysis after being given a muscle relaxant called suxamethonium during surgery. This temporary paralysis is called suxamethonium apnoea. To investigate the cause of temporary paralysis following treatment

When:
If you or a close relative have experienced suxamethonium apnoea after a surgical operation.

To indicate possible insecticide poisoning with recent or frequent use of organic phosphorus insecticides. Occupational exposure can occur in workers involved with agriculture or the organic chemical industry.

Test General info:
There are two similar cholinesterase enzymes in the body; butrylcholinesterase (pseudocholinesterase) found in the blood plasma, intestine and white matter of the brain, and acetylcholinesterase found in red blood cells, grey matter of the brain and nerve


Why:
To screen for a rare mutation in the PSEN1 gene known to be associated with Early Onset Familial Alzheimer’s Disease (EOFAD)

When:
If you are an adult who has symptoms of dementia and a strong family history of early onset Alzheimer’s Disease (AD that begins before age 60-65) or if you are an adult with no symptoms but with an identified PSEN1 genetic mutation (and EOFAD) in your family

Test General info:
This test looks for mutations in the PSEN1 gene, which have been associated with Early Onset Familial Alzheimer’s Disease (EOFAD). Although most AD starts after the age of 65 (late onset), about 5-10% of cases of the disease begin in people under 65 years


Related Tests:
TB tests, AFB Smear and Culture, Body Fluid Analysis, Pleural Fluid Analysis

Why:
To help detect or rule out a Mycobacterium tuberculosis infection in pleural fluid in order to assist in the diagnosis of tuberculosis; rarely to detect the infection in other body fluids such as peritoneal fluid or cerebrospinal fluid (CSF)

When:
When a doctor suspects that someone with chest pain, coughing, and/or difficulty breathing has tuberculosis that has spread from their lungs to the pleurae (lining around the lungs)

Sample Type:
A volume of pleural fluid is collected by a doctor using a procedure called thoracentesis; other body fluids are collected using other procedures

Test General info:
Adenosine deaminase (ADA) is a protein that is produced by cells throughout the body and is associated with the activation of lymphocytes, a type of white blood cell that plays a role in the immune response to infections. Conditions that trigger the immun

Related Diseases:
Conditions: Tuberculosis, Nontuberculous Mycobacteria, Lung Diseases


Other Names:
Antidiuretic Hormone; Vasopressin; Arginine Vasopressin; AVP

Related Tests:
Osmolality, Creatinine, Sodium, Urea, Urinalysis

Why:
To help detect, diagnose, and determine the cause of antidiuretic hormone (ADH) deficiency or excess. However, this test is not widely used; diagnoses of conditions of ADH excess/ deficiency are usually based on clinical history and other laboratory tests

When:
ADH may be requested if results of initial investigations of ADH deficiency/ excess are equivocal. However, ADH analysis is rarely required.

Test Prep:
Alcohol and some medications (including diuretics) can interfere with ADH secretion or its action. Talk to your doctor to identify any medications that should be discontinued before the test.
An ADH test may be requested as part of a water deprivation te

Test General info:
The ADH test measures the amount of antidiuretic hormone (ADH) in the blood. ADH, also called arginine vasopressin (AVP), is a hormone produced by the hypothalamus and stored in the posterior pituitary gland. Antidiuretic hormone helps regulate water bala

Related Diseases:
Conditions: Pituitary Disorders, Kidney Disease


Other Names:
Dopamine; adrenaline (epinephrine); noradrenaline (norepinephrine); free urine catecholamines

Related Tests:
Plasma free metadrenalines; urine metadrenalines; fractionated urine metadrenalines

Why:
To help diagnose or rule out a phaeochromocytoma or other neuroendocrine tumour

When:
If you have symptoms of persistent or episodic high blood pressure such as severe headaches, rapid heart rate and sweating

Sample Type:
A 24-hour urine sample (collected into a bottle containing a small amount of acid) or possibly a blood sample taken from a vein in the arm
Note: These tests are affected by certain drugs, foods, and stresses. Inform your doctor of any medicines you are t

Test Prep:
You may be asked to lie down and rest quietly for 15-30 minutes prior to sample collection, and your blood may be collected while you are lying down. In other circumstances, you may just be seated upright with little or no rest time before the sample coll

Test General info:
Catecholamines are a group of similar hormones produced in the medulla (central portion) of the adrenal glands. The adrenal glands are small, triangular organs which sit on top of each kidney. The main catecholamines are dopamine, adrenaline (epinephrine)


Other Names:
Search
Help? Tests List of all tests and acronyms Test not listed? 5-HIAA 17-Hydroxyprogesterone ACE ACR ACT ACTH Adenosine Deaminase ADH AFB Smear and Culture AFP Tumour Marker Albumin Aldosterone Allergy Test ALP Alpha-1 Antitrypsin ALT AMA Ammonia Amn

Related Tests:
Gram stain; Susceptibility testing; Blood culture; Urine culture; AFB smear and culture; Fungal culture; MRSA screening

Why:
To detect a bacterial wound infection, to determine which specific bacteria are present, and to isolate and grow the bacteria for subsequent susceptibility testing

When:
When the doctor suspects that your wound is infected by a pathogenic microorganism

Sample Type:
Usually a sterile swab used to collect cells or pus from the site of the suspected infection. Occasionally aspirations of fluid from deeper wounds into a syringe and/or a tissue biopsy may be required.

Test General info:
A bacterial wound culture is a test that is used to detect and identify pathogenic bacteria in a potentially infected wound. Wounds may be superficial breaks in the skin such as scrapes, cuts and scratches or may involve deeper tissues such as incisions,

Related Diseases:
Conditions: Wound and Skin Infections, Staph Wound Infections and Methicillin Resistant Staphylococcus aureus


Why:
To screen for and monitor therapy for certain cancers of the liver and testes

When:
If your doctor suspects that you have certain cancers of the liver or testes, if you are under treatment for them, or have previously been treated for one of these cancers. It may also be used if chronic hepatitis or cirrhosis of the liver is suspected.

Sample Type:
A blood sample taken from a vein in the arm
The Test Sample

Test General info:
AFP is a protein that is normally produced by the developing fetus. However, it can also be produced by certain tumours and disease of the liver. Raised levels of AFP are found in the majority of patients with a type of liver cancer called hepatocellular

Related Diseases:
Conditions: Liver cancer, Testicular cancer


Formal Name:
Human immunodeficiency virus (HIV) antibody test

Related Tests:
p24 antigen test; HIV resistance testing; HIV viral load; CD4 and CD8 lymphocyte counts

Why:
To determine if you are infected with human immunodeficiency virus (HIV)

When:
Three or four weeks after you think you may have been exposed to the virus; once a year if you are at risk of being exposed to the virus; when you doctor thinks your symptoms may be due to HIV; before becoming pregnant or during pregnancy

Sample Type:
A blood sample collected from a vein in your arm; the test can also be performed on urine or saliva (spit)

Test General info:
Human immunodeficiency virus (HIV) causes AIDS (acquired immunodeficiency syndrome) by slowly destroying the over a period of years, leaving the body vulnerable to debilitating infections. This test detects HIV antibodies produced by the body that can be

Related Diseases:
Conditions: Human Immunodeficiency Virus (HIV), Sexually Transmitted Diseases
Features: Blood Banking: Donating Blood
Screening: Pregnancy Screening: Pre-Conception and First Trimester


Formal Name:
[Primary tests]; Delta-aminolaevulinic acid (ALA); porphobilinogen (PBG); porphyrins

Why:
To help diagnose and sometimes to monitor porphyrias (a group of inherited disorders involving disturbance in the metabolism of haem, a component of haemoglobin)

When:
If a patient has symptoms that suggest an acute porphyria (such as abdominal pain, tingling in hands or feet, and/or confusion or hallucinations) or a cutaneous porphyria (such as reddening, blistering, or scarring on sun-exposed skin)

Sample Type:
A blood sample taken from a vein in your arm, a random urine sample, preferably collected whilst symptoms are occurring, and a small stool sample

Test Prep:
None required, but preferably collect samples when symptoms are occuring
The Test

Test General info:
Porphyrin tests are assays that are used to help diagnose, and monitor a group of disorders called porphyrias. Most porphyrin tests detect and measure by-products of the synthesis of haem, a part of haemoglobin (the protein inside red blood cells that all


Related Tests:
AST, ALP, GGT, bilirubin, liver function tests

When:
If your doctor thinks that you have symptoms of a liver disorder

Test Prep:
No test preparation is needed, although you should inform your doctor about any drugs you are taking.
The Test

Test General info:
ALT is an enzyme found mostly in the liver; smaller amounts are also found in the kidneys, heart, and muscles. When the liver is damaged, ALT is released into the bloodstream, hence increasing the concentration that can be detected in a blood test. This o

Related Diseases:
Conditions: Liver disease, Hepatitis, Alcoholism, Wilson Disease, Haemochromatosis


When:
If your doctor thinks you have symptoms of liver or kidney disease or prior to a planned surgery

Test General info:
Albumin is the most abundant protein in the blood plasma. It keeps fluid from leaking out of blood vessels; nourishes tissues; and carries hormones, vitamins, drugs, and ions like calcium throughout the body. Albumin is made in the liver and its concentra

Related Diseases:
Conditions: Liver disease, Kidney disease


Related Tests:
Drugs of Abuse Screen; Full Blood Count (FBC); Glucose; Electrolytes

Why:
To find out if a person has drunk alcohol and to measure the amount of alcohol present.

When:
When a patient has symptoms that suggest alcohol toxicity or when a person is suspected of breaking drinking-related laws or as part of a drug testing panel for pre-employment or other purposes.

Sample Type:
Ethanol (Ethyl alcohol) can be measured in blood sample, urine, saliva or in breath. Blood, urine, and saliva samples must be sent to a laboratory for analysis. A breath sample is analysed immediately on site using a Breathalyzer.
The Test Sample

Test General info:
This test measures the amount of ethanol in the blood, urine, breath, or saliva. Ethanol (also called ethyl alcohol or alcohol) has been consumed by civilizations throughout the world for thousands of years. Small amounts of ethyl alcohol can cause excite


Why:
To see if your aldosterone or renin levels are abnormal; to detect hyperaldosteronism (overproduction of aldosterone) or hypoaldosteronism (underproduction of aldosterone)

When:
If your doctor finds an electrolyte imbalance or you develop symptoms of hyperaldosteronism, such as high blood pressure or muscle weakness

Sample Type:
A blood sample taken from a vein in your arm or a 24-hour urine sample

Test Prep:
You may be asked to adhere to an unrestricted salt diet prior to the test or to temporarily discontinue one or more medications. Please follow any instructions you are given, as this is important to ensure the validity of test results.
The Test

Test General info:
Aldosterone is a hormone which regulates the retention of sodium (salt) and water by the kidney and also regulates the removal of potassium. It plays an important role in the control of blood pressure.
Aldosterone is produced by the adrenal glands which

Related Diseases:
Condition: Addison`s Disease, Conn`s Syndrome, Cushing`s Syndrome


Related Tests:
AST; ALT; GGT; Bilirubin; Liver function tests; Bone markers

Why:
To screen for or monitor treatment for a liver or bone disorder

When:
As part of liver function tests or when a person has symptoms of a liver or bone disorder

Sample Type:
A blood sample taken from a vein in the arm

Test Prep:
Fasting is preferred but not required for this test. Eating a meal can increase the ALP level slightly for a few hours in some people. It is usually better to do the test after fasting overnight. In this case, only water is permitted.
The Test

Test General info:
Alkaline phosphatase is an enzyme found in high levels in bone and liver. Smaller amounts of ALP are found in the placenta of women who are pregnant, and in the intestines. Each of these body parts makes different forms of ALP. The different forms are cal


Related Tests:
Total IgE, Full blood count (FBC), White blood cell differential count , Eosinophil count, Basophil count

When:
When you have symptoms such as hives, dermatitis, rhinitis (nasal blockage, sneezing), red itchy eyes, asthma, or severe reactions such as anaphylaxis that your doctor suspects may be caused by an allergy

Test General info:
Immunoglobulin E (IgE) is a protein involved with allergic reactions; it is normally found in very small amounts in the blood. IgE is an antibody that functions as part of the body`s immune system and helps to defend against ``intruders``. When someone wi


Formal Name:
Antimitochondrial Antibody and Antimitochondrial M2 Antibody

Related Tests:
Antineutrophil cytoplasmic antibody (ANCA), Liver/Kidney microsomal antibody, Alkaline phosphatase (ALP), Alanine aminotransferase (ALT), Liver panel, Smooth muscle antibody (SMA), Antinuclear antibody (ANA)

Why:
To help diagnose primary biliary cirrhosis (PBC)

When:
When a doctor suspects that a person may have primary biliary cirrhosis

Test General info:
This test measures whether antimitochondrial antibodies (AMA) are present in the blood. Moderate or high levels of AMA are strongly associated with primary biliary cirrhosis (PBC). PBC is an autoimmune disorder that causes inflammation and scarring of the


Other Names:
AMH; Mullerian-inhibiting hormone; MIH; Mullerian inhibiting factor; MIF; Mullerian-inhibiting substance; MIS

Related Tests:
FSH, LH, Oestrogen, Testosterone, Progesterone, 17-Hydroxyprogesterone (17-OHP), Antral follicle count

Why:
In the UK, measurement of anti-Müllerian hormone (AMH) has three generally accepted uses (based on published evidence):
To help guide treatment of women undergoing assisted conception procedures. 
As part of an investigation of abnormal sexual developme

When:
Some women are tested when they are referred for assisted conception procedures e.g. in vitro fertilisation (IVF). The result can help the doctor to provide appropriate treatment which is individualised to the patients needs. 
As part of an extended newborn screen, when an infant has ambiguous genitalia (i.e. it is not clear whether the baby is a boy or a girl). 
AMH may be tested to monitor the response to treatment and tumour recurrence in women with an AMH-secreting ovarian tumour.

Sample Type:
A blood sample taken from the vein in your arm or from a heal prick in an infant

Test General info:
The test measures a hormone called anti – Müllerian hormone (AMH). This hormone is very important during the development of the male foetus as it is essential for the formation of male reproductive organs. 
In males, AMH is generated within cells in the

Related Diseases:
Conditions: Infertility
In the News: Study finds hormone is useful for predicting success of in vitro fertilisation


Test Name:
Aminophylline, Nuelin, Phyllocontin, Slo-Phyllin, Uniphyllin

Other Names:
Aminophylline, Nuelin, Phyllocontin, Slo-Phyllin, Uniphyllin

Related Tests:
Therapeutic Drug Monitoring; Emergency and Overdose Drug Testing

Why:
To measure the amount of theophylline or caffeine in the blood, to establish an appropriate dose and to maintain an appropriate level

When:
At the start of drug therapy and at regular intervals to monitor the drug’s levels; when indicated, to detect low or possible toxic concentrations

Sample Type:
A blood sample taken from a vein in your arm or from pricking an infant’s heel

Test Prep:
No specific test preparation is needed.
The Test

Test General info:
Theophylline and caffeine are methylxanthines – drugs that ease and stimulate breathing. These tests measure the amount of theophylline or caffeine in the blood to help establish an appropriate dose and maintain the right level. Theophylline is one of sev


When:
If a patient experiences mental changes or lapses into a coma of unknown origin; if an infant or child experiences frequent vomiting and increased lethargy as a newborn or about a week after a viral illness

Sample Type:
A blood sample taken from a vein or artery in your arm

Test Prep:
Avoid smoking cigarettes prior to collection of the specimen and follow any other instructions that you are given.
The Test

Test General info:
This test measures the concentration of ammonia in the blood. Ammonia is a chemical produced by bacteria in the intestine and by cells in the body during the processing of proteins.  Ammonia is a poisonous waste product which is normally transported to th


Other Names:
Amniocentesis; Foetal Lung Maturity Tests

Related Tests:
Triple/Quad Screen; Maternal AFP (alpha-fetoprotein); Blood Typing; Bilirubin; First Trimester Down Syndrome Screen; Chorionic Villus Sampling; fFN (Foetal fibronectin); Chromosome Analysis

Why:
To detect and diagnose some birth defects, genetic diseases, and chromosome abnormalities in a foetus, especially if pregnancy screening tests are abnormal; to help diagnose and monitor haemolytic disease in a foetus

When:
Between 15 and 20 weeks of gestation to test for genetic diseases, chromosome abnormalities, and open neural tube defects; when it is suspected that a foetus has haemolytic disease, about every 14 days

Sample Type:
A sample of amniotic fluid is obtained using a procedure called amniocentesis

Test Prep:
Depending upon the gestational age of the foetus, either a full or empty bladder may be required at the time the amniocentesis is performed. Be sure to follow any instructions that you are given.
The Test

Test General info:
Amniotic fluid surrounds, protects, and nourishes a growing foetus during pregnancy. It allows the baby to move relatively freely, keeps the umbilical cord from being compressed, and helps maintain a stable temperature. Contained within the amniotic sac,

Related Diseases:
Conditions: Pregnancy & Prenatal Testing, Neural Tube Defects, Down Syndrome, Thalassemia, Cystic Fibrosis, Sickle Cell Anaemia
Articles: Universe of Genetic Testing


When:
If you have symptoms of a pancreatic disorder, such as severe abdominal pain, fever, loss of appetite or nausea

Test General info:
Amylase is an enzyme made mainly by the pancreas. It is released from the pancreas into the digestive tract to help digest starch in our food. It is usually present in the blood in small quantities. When cells in the pancreas are injured or if the pancrea

Related Diseases:
Conditions: Cystic Fibrosis, Pancreatic Cancer, Pancreatic Disease, Pancreatitis


Why:
To diagnose pancreatitis or other pancreatic diseases


Other Names:
Fluorescent antinuclear antibody (FANA), ANA ELISA

Related Tests:
Anti-dsDNA antibodies, anti-Sm antibodies, Sjögren`s syndrome antigen (SSA, SSB); Scl-70 antibodies; anti-centromere antibodies; anti-histone antibodies; anti-RNP antibodies, PM-Scl, Anti-Jo-1 antibodies, Anti-PL-7, PL12, Anti SRP

Why:
To help diagnose systemic lupus erythematosus (SLE), drug induces SLE-like syndrome, Sjogren`s syndrome, scleroderma and  certain other autoimmune connective tissue diseases.

When:
If your doctor thinks that you have symptoms of SLE, drug-induced lupus, Sjogren`s syndrome, scleroderma or another autoimmune connective tissue disease

Test Prep:
No test preparation is needed; however, some drugs interfere with the test, so tell your doctor about any medications you are taking.
The Test

Test General info:
The ANA test identifies the presence of antinuclear antibodies (ANA) in blood. These antibodies are produced by the body`s immune system – the body`s defence system against invasion by foreign substances such as viruses and bacteria. Sometimes the immune

Related Diseases:
Conditions: Systemic Lupus Erythematosus (SLE)


Other Names:
Citrulline antibody; Anti-citrulline antibody; anti-cyclic citrullinated peptide antibody; anti-CCP

Why:
To help in the diagnosis of rheumatoid arthritis (RA) and differentiate it from other types of arthritis; sometimes to help evaluate the prognosis of a patient with RA

When:
If a patient has joint inflammation and/or undiagnosed or undifferentiated inflammatory polyarthritis (symptoms may suggest but do not yet meet the criteria of RA) and the doctor suspects RA

Test General info:
The cyclic citrullinated peptide antibody (CCP) test is a relatively new assay that detects the presence of anti-citrulline antibodies in the blood. Citrulline is an unusual amino acid (protein building block), which is created when the amino acid arginin

Related Diseases:
Conditions: Rheumatoid Arthritis, Autoimmune Disorders


Other Names:
Antibody to ds-DNA; Native double-stranded DNA antibody; anti-DNA; Double stranded DNA antibody

Related Tests:
ANA, ENA Panel, Anti-Sm, Anti-RNP, Anti-Ro (SSA), Anti-La (SSB), Autoantibodies

Why:
To help diagnose and monitor systemic lupus erythematosus (SLE)

When:
When you have symptoms associated with SLE and a positive ANA test; periodically when you have been diagnosed with SLE

Test General info:
This test measures the amount of antibody to double-stranded deoxyribonucleic acid (anti-dsDNA) that may be present in the blood. Anti-dsDNA is an autoantibody, produced when a person`s immune system fails to distinguish between ``self`` and ``non-self``

Related Diseases:
Conditions: Systemic Lupus Erythematosus, Autoimmune Disorders, Sjogren Syndrome, Scleroderma


Related Tests:
Hepatitis B antibodies; hepatitis C antibodies, liver function tests

Why:
To diagnose an infection with hepatitis A virus, or to find out the need for or the response to hepatitis A vaccination

When:
If you have symptoms of an infection with or have been exposed to the hepatitis A virus; to detect previous infection or vaccination

Test General info:
Hepatitis A antibodies are produced in response to an infection with the hepatitis A virus. The test detects the presence of this antibody.


Other Names:
HBV; Hep B; Hepatitis B; anti-HBs; Hepatitis B surface antibody; HBsAg; Hepatitis B surface antigen; HBeAg; Hepatitis B e-antigen; Anti-Hbe; Hepatitis e antibody; anti-HBc; Hepatitis B total core antibody; anti-HBc IgM; Hepatitis B core IgM; HBV DNA

Related Tests:
Hepatitis A; hepatitis C; acute/chronic hepatitis panel; bilirubin; AST; ALT; GGT

Why:
To detect, diagnose and follow the course of an infection with hepatitis B virus (HBV) or to determine if the vaccine against hepatitis B has produced the desired level of immunity

When:
If you have symptoms of a hepatitis B infection or are likely to have been exposed to the virus; if you have chronic liver disease (possibly due to some other cause), if you have received the vaccine, if you were born to a mother who was HBV positive or if you are being treated for HBV

Test General info:
Hepatitis B is a liver infection caused by the hepatitis B virus (HBV). It is one of several various causes of hepatitis, a condition characteriszed by inflammation and enlargement of the liver. Other causes of hepatitis include, for example, certain drug

Related Diseases:
Conditions: Viral hepatitis, Liver Disease


Other Names:
Thyroid autoantibodies; Anti-thyroid antibodies; Anti-microsomal antibody; Thyroid microsomal antibody; Thyroid peroxidase antibody; TPOAb; Anti-TPO; TBII; Antithyroglobulin antibody; TgAb; TSH receptor antibody; TRAb; Thyroid stimulating immunoglobulin;

Formal Name:
Thyroid peroxidase antibody (TPOAb); Thyroglobulin antibody (TgAb); Thyroid stimulating hormone receptor antibody (TRAb)

Why:
To help diagnose and monitor autoimmune thyroid diseases and to distinguish these from other forms of thyroiditis, and thyroid disease; to help guide treatment decisions

When:
If you have an enlarged thyroid gland (goitre) and/or if your other thyroid tests (such as Free T3, Free T4, and TSH) indicate thyroid dysfunction; if there are clinical features to suggest thyroid disease; in some patients with related autoimmune diseases

Test General info:
These tests detect the presence and measure the quantity of specific thyroid autoantibodies. These develop when a person’s immune system mistakenly recognizes components of the thyroid as foreign (not-self) and can lead to chronic thyroiditis (inflammatio

Related Diseases:
Conditions: Thyroid diseases, Graves’ disease, Hashimoto’s thyroiditis, Autoimmune disorders


Related Tests:
Antinuclear antibody (ANA); Aspartate aminotransferase (AST); Bilirubin; Antimitochondrial antibody (AMA); F-Actin Antibody; Anti-cytoskeleton antibodies (ACTA)

Why:
To help diagnose autoimmune hepatitis and distinguish it from other causes of liver injury

When:
When a patient has hepatitis that the doctor suspects may be due to an autoimmune-related process

Test General info:
This test looks for the presence (and if present the level) of smooth muscle antibodies (SMA) in the blood. Antibodies usually protect the body against infecting organisms such as  bacteria and viruses. However, antibodies which are produced against parts

Related Diseases:
Autoimmune disorders, Liver disease, Hepatitis


Other Names:
Anti-Xa; Xa inhibition; Antifactor Xa heparin; Heparin level

Why:
To monitor low molecular weight heparin (LWMH) therapy and sometimes to monitor unfractionated heparin (UFH) therapy

When:
When you are being treated with LMWH or UFH and your doctor wants to monitor the amount of heparin in your blood

Test General info:
This test measures the effect of low molecular weight heparin (LMWH) or unfractionated heparin (UFH) in the blood by measuring anti-Xa activity. Heparin is an anticoagulant, a drug that inhibits blood clotting. Heparin molecules vary in size and activity.


Formal Name:
Cardiolipin Antibodies, IgG, IgM, and IgA

Related Tests:
Antiphospholipid Antibodies;  Anti-beta2 glycoprotein I;  Anti-phosphatidylserine;  Lupus Anticoagulant Panel

Why:
To help investigate unexplained blood clot formation, to help determine the cause of recurrent miscarriage, or as part of an evaluation for antiphospholipid syndrome

When:
When you have had one or more unexplained venous or arterial thrombotic episodes; when you have had recurrent miscarriages, especially in the 2nd and 3rd trimesters

Test General info:
These tests detect the presence of three classes (IgG, IgM, and/or IgA) of cardiolipin antibodies. Produced by the immune system in response to a perceived threat, these proteins are the most common antiphospholipid antibodies. They are acquired  autoanti


Test Name:
Antimitochondrial Antibody and Antimitochondrial M2 Antibody


Related Tests:
HDL, LDL, Lipid Profile, Cholesterol, Apo B

Why:
To determine whether or not you have adequate levels of Apo A-I, and to help determine your risk of developing coronary heart disease (CHD)

When:
When you have hyperlipidaemia and/or a family history of CHD or peripheral vascular disease; when your doctor is trying to assess your risk of developing heart disease; when you are monitoring the effectiveness of lipid treatment and/or lifestyle changes

Sample Type:
Usually, a blood sample taken from a vein in your arm
The Test Sample

Test General info:
Apolipoproteins are the protein component of lipoproteins - complexes that transport lipids throughout the bloodstream. Apolipoproteins provide structural integrity to lipoproteins and shield the hydrophobic (water repellent) lipids at their centre.

Mo

Related Diseases:
Tests: Cholesterol, HDL, LDL, Triglycerides, Lipid Profile, Apo B, hs-CRP, Homocysteine
Conditions: Heart attack, Stroke, Congestive heart failure, Angina


Related Tests:
LDL, Lipid profile, Cholesterol, Apo A, HDL, Lp(a), hs-CRP, Homocysteine, Cardiac Risk Assessment, Apo B/Apo A-1 ratio

Why:
To help evaluate your risk of developing cardiovascular disease (CVD)

When:
When you have a personal or family history of heart disease and/or high concentrations of lipids in the blood (hyperlipidaemia) and your doctor is trying to determine your risk of developing CVD; sometimes measured to help monitor treatment for hyperlipidaemia or to help diagnose a rare apo B deficiency

Test Prep:
No special preparation is needed for an apolipoprotein B test. However, this test is often requested at the same time as other tests that do require fasting (water only), such as LDL-C, HDL-C and triglycerides. Therefore, you may be instructed to fast for

Test General info:
This test measures the amount of apolipoprotein B (apo B) in the blood. Apolipoproteins are the protein component of lipoproteins, complexes that transport lipids throughout the bloodstream. Apolipoproteins provide structural support to lipoproteins and s

Related Diseases:
Conditions: Heart attack, Stroke, Congestive heart failure, Angina, CVD


Related Tests:
Cardiac Risk Assessment, HDL Cholesterol, LDL Cholesterol, Lipid Profile, Triglycerides, Tau Protein

Why:
To help confirm a diagnosis of Type III hyperlipoproteinaemia (also known as dysbetalipoproteinaemia), to evaluate a possible genetic cause of atherosclerosis, or to help confirm a diagnosis of late onset Alzheimer’s Disease (AD) in a symptomatic adult

When:
If your doctor suspects that your high cholesterol and triglyceride concentrations may be due to a genetically inherited disorder, or if you have xanthomas (yellowish raised patches) on your skin; also sometimes used if you have progressive symptoms of dementia and your doctor wants to investigate a possible cause of Alzheimer`s Disease

Test General info:
The test looks at a patient`s DNA to determine what combination of Apo E gene alleles (copies) he or she has. The ApoE gene exists in three different forms – e2, e3, and e4 – with e3 being the most common form and considered to be `neutral`. Everyone has


Why:
To determine if you have an imbalance in the amount of oxygen gas (O2) or carbon dioxide gas (CO2) in your blood or an acid-base imbalance (i.e. if your blood is too acidic/ alkaline), which may indicate a respiratory (lung/breathing), metabolic, or kidne

When:
If your doctor suspects that you have symptoms of an oxygen/carbon dioxide imbalance or an acid-base imbalance. These include difficulty breathing, shortness of breath, or rapid breathing (hyperventilation). You may also be tested to monitor the effectiveness of oxygen therapy (used when you have a condition that causes an oxygen shortage) and during operations to monitor your blood`s oxygen and carbon dioxide levels. If you have chronic obstructive pulmonary disease (COPD) this test may be used to assess if you need long term oxygen therapy.

Sample Type:
A blood sample collected from an artery, usually the radial artery in the wrist (located on the inside of the wrist, below the thumb, where you can feel your pulse). A capillary blood from a heel-prick may be used for babies

Test Prep:
Typically, no test preparation is needed. However, if you are on oxygen therapy, the oxygen may either be turned off for 20 to 30 minutes before the collection for a ``Room Air`` test or, if this cannot be tolerated or if the doctor wants to check your ox

Test General info:
Blood gas tests tell your doctor if you have enough oxygen in your blood and whether or not your blood pH is balanced - not too acidic (acidosis) or too alkaline/basic (alkalosis). Blood gas tests directly measure: 
pH – a measure of the level of hydroge

Related Diseases:
Conditions: Kidney disease, Acidosis and Alkalosis, Lung diseases, Asthma, Pneumonia


Other Names:
Aspartate aminotransferase; serum glutamic-oxaloacetic transaminase (SGOT)

Related Tests:
ALT; ALP; GGT; bilirubin; liver function tests

Test General info:
AST is an enzyme found mostly in the heart and liver and to a lesser extent in skeletal muscle. When heart, liver or muscle cells are injured, they release AST into the bloodstream.

Related Diseases:
Conditions: Liver disease, Hepatitis, Alcoholism


Formal Name:
B1 (thiamine or thiamin); B2 (riboflavin); B3 (niacin); B5 (pantothenic acid); B6 (pyridoxal phosphate, pyridoxine); B7 (biotin)

Why:
To screen for and detect moderate to severe vitamin B deficiencies

When:
When someone has symptoms that may be due to a B vitamin deficiency, is at risk for a deficiency, or has a condition associated with malabsorption

Sample Type:
A blood sample taken from a vein in your arm.

Test Prep:
The blood sample is usually collected in the morning after an overnight fast, preferably before taking any medication.
The Test

Test General info:
The B vitamins are nutrients that the body requires in small amounts (micronutrients) for metabolism, energy production, and for cell, skin, bone, muscle, organ, and nervous system health. B vitamin tests measure these specific compounds in the blood to h

Related Diseases:
Conditions: Alcoholism, Coeliac Disease, Malnutrition, Vitamin B12 Deficiency, Malabsorption


Test Name:
B-cell Gene Clonality Molecular Genetic Tests

Other Names:
Immunoglobulin Gene Rearrangement; B-cell Gene Clonality Molecular Genetic Tests; BCGR

Related Tests:
Full Blood Count (FBC), White Blood Cell Differential, Blood Film, Immunophenotyping, Chromosome Analysis, Bone Marrow Aspiration and Biopsy, Quantitative Immunoglobulins, T-cell Receptor Gene Rearragement

Why:
To help diagnose a B-cell lymphoma; to detect and evaluate residual cancer cells

When:
When a doctor thinks that you may have a B-cell lymphoma; sometimes to evaluate the effectiveness of treatment or to evaluate for recurrent disease

Sample Type:
A bone marrow, tissue (biopsy), or body fluid sample collected by your doctor; sometimes a blood sample drawn from a vein in your arm

Test General info:
This test detects characteristic changes (rearrangements) in specific genes in B-cells. This information can be helpful in diagnosing a B-cell lymphoma.
B-cells are a type of lymphocyte (a kind of white blood cell, WBC) that produces antibodies in respon

Related Diseases:
Conditions: Lymphoma, Leukaemia, Bone Marrow Disorders


Other Names:
Brain natriuretic peptide, NT-proBNP, N terminal pro B type natriuretic peptide, natriuretic peptides

Why:
To diagnose the presence and severity of heart failure

When:
If you have symptoms of heart failure, such as breathlessness and fatigue, or if you are being treated for heart failure

Test General info:
This test measures the concentration of BNP or NTproBNP in the blood. NTproBNP is an inactive fragment produced at the same time as BNP. BNP is a hormone that helps to regulate blood volume. Both BNP and NT-proBNP are mainly produced by the heart`s left v


Why:
To find out whether you have human leucocyte antigen B27 (HLA-B27) on the surface of your cells; to help assess whether you might have an autoimmune disorder associated with the presence of HLA-B27

When:
When you have symptoms of chronic inflammation, pain, and stiffness in certain areas of your body, such as your back, neck, and chest, or the interior portion of your eyes uveitis, especially if you are male and the symptoms began between late teens and your early 30s

Test General info:
HLA-B27 is a particular antigen found in certain people and the gene that codes for its production. It is one of many human leucocyte antigens (HLA). Human leucocyte antigens are a group of proteins that help the body`s immune system identify its own cell

Related Diseases:
Conditions: Autoimmune Disorders, JRA, Ankylosing Spondylitis, Reactive Arthritis


Related Tests:
Cholesterol; HDL; Triglycerides; Lipid profile

Why:
To determine your chances of developing cardiovascular disease

When:
Aged 40 as part of a routine cardiovascular health check, or if you are already thought to be at risk of cardiovascular disease for another reason, or to monitor your response to treatments which lower LDL-C.

Sample Type:
A blood sample taken from a vein in the arm, or occasionally from a fingerprick

Test Prep:
A test for LDL-C typically requires a 12-hour fast, with only water permitted during this time. Your doctor might recommend a slightly shorter or longer fast. Strictly speaking, if LDL-C is being measured directly, rather than calculated using an equation

Test General info:
Cholesterol is carried in the blood by proteins called “lipoproteins”. There are a number of different types of lipoproteins, which are named after how dense they are. LDL stands for ‘low-density lipoprotein’, and any cholesterol carried by LDL is known a


Other Names:
BCR/ABL1; bcr-abl oncogene; BCR-ABL Kinase Domain Mutation Analysis

Related Tests:
Philadelphia chromosome; Fluorescent In Situ Hybridisation (FISH); FBC; Bone Marrow Aspiration and Biopsy; Blood Film; Differential

Why:
To help diagnose and monitor the treatment of chronic myeloid leukaemia (CML) and a type of acute lymphoblastic leukaemia (ALL)

When:
When you have results of a FBC and/or signs and symptoms that suggest that you may have leukaemia; periodically when you are being treated for CML or BCR-ABL-positive ALL

Sample Type:
A blood sample taken from a vein in your arm or a bone marrow sample collected using a bone marrow aspiration and/or biopsy procedure

Test General info:
BCR-ABL refers to a gene sequence found in an abnormal chromosome 22 of some people with certain forms of leukaemia. Humans normally have 23 pairs of chromosomes, including 22 pairs of non-sex-determining chromosomes (also known as autosomes) and 1 pair o

Related Diseases:
Conditions: Leukaemia
Features: The Universe of Genetic Testing


Other Names:
Beta 2 transferrin; desialated transferrin

Why:
To help identify cerebrospinal fluid (CSF) fluid leaking from the skull.

When:
If there is a watery discharge from your nose or ear (rhinorrhoea or otorrhoea) after you have suffered a skull fracture or after brain surgery.

Sample Type:
A sample of the suspicious watery discharge is collected into a plastic tube and at the same time a blood sample is also collected.
The Test Sample

Test General info:
Cerebrospinal fluid (CSF) is normally found only within the brain and the spinal canal. If you suffer an injury which causes a tear in the membranes covering the brain and spine, CSF may leak out. This may sometimes cause watery fluid to drip from either


Other Names:
Pregnancy test; qualitative hCG; quantitative hCG; beta hCG

Why:
To confirm and monitor pregnancy or to diagnose trophoblastic disease or germ cell tumours

When:
As early as 10 days after a missed menstrual period (some methods can detect hCG even earlier, at one week after conception) or if a doctor thinks that your symptoms suggest ectopic pregnancy, a failing pregnancy, trophoblastic disease or germ cell tumours
Human chorionic gonadotrophin (hCG) is also tested as part of the prenatal screening program for Down’s syndrome.

Sample Type:
A urine sample collected first thing in the morning or a blood sample taken from a vein in the arm

Test Prep:
None needed; however, do not drink large amounts of fluid before collecting a urine sample for a pregnancy test because overly dilute urine may result in a false negative test result.
The Test

Test General info:
Human chorionic gonadotrophin (hCG) is a hormone produced in the placenta of a pregnant woman. A pregnancy test is a specific blood or urine test that can detect hCG and confirm or exclude pregnancy. The hormone can be detected 10 days after a missed mens


When:
May be part of a routine blood test that includes electrolyte measurements or may be requested by your doctor if you have a medical condition or are experiencing symptoms that could indicate problems with the acid-base balance of your body

Test General info:
When you breathe, you bring oxygen (O2) into your lungs and release carbon dioxide (CO2). Carbon dioxide in your blood is present in three forms: carbonic acid (H2CO3), CO2 dissolved in blood, and bicarbonate (HCO3-), the predominant form. Bicarbonate is

Related Diseases:
Tests: Electrolytes, Blood gases, anion gap
Conditions: Acidosis and Alkalosis, Lung Diseases, Addison`s Disease, Cushing Syndrome, Conn Syndrome, Kidney Disease, Hypertension


Other Names:
Total bilirubin, conjugated or direct bilirubin, unconjugated or indirect bilirubin

Related Tests:
AST, ALT, ALP, GGT, liver function tests

Why:
To screen for and monitor liver disorders, such as cirrhosis. To help detect certain rare genetic disorders in sick babies and to avoid brain damage in babies who are markedly jaundiced.

When:
If your doctor thinks you have symptoms or signs of liver damage, liver disease, bile duct blockage, haemolytic anaemia or a liver-related metabolic problem.

Sample Type:
In adults, a blood sample from a vein in the arm; in newborns, a blood sample from a heel-prick

Test Prep:
No test preparation is necessary. The blood sample should ideally be protected from bright light before analysis.
The Test

Test General info:
Bilirubin is an orange-yellow pigment found in bile. The normal life-span of red blood cells in the circulation is 120 days. When they are broken down the pigment giving them their characteristic red colour, haemoglobin, (whose role is to carry oxygen to


Related Tests:
HDL; LDL; Triglycerides; Lipid profile; Cardiac risk assesment

Why:
To screen for risk of developing heart disease

When:
If you already know you have heart disease (angina, heart attack) 
If there is a family history of high cholesterol, or of heart disease at an early age 
If you have risk factors which put you at an increased chance of developing heart disease, such as diabetes, high blood pressure, or you are a smoker 
If you are taking drugs to lower your cholesterol level

Sample Type:
A blood sample taken from a vein in the arm or a finger
The Test Sample

Test General info:
Cholesterol is a substance that is essential for life. It helps form the membranes for cells in all organs and tissues in your body. It is used to make hormones that are essential for development, growth and reproduction. It forms bile acids that are need


Other Names:
Factor assays; blood clotting factors; clotting factors; or by the individual factor number (Factor I, Factor II, etc.) or name (Fibrinogen, Prothrombin, etc.)

Related Tests:
Prothrombin Time (PT), Activated Partial Thromboplastin Time (aPTT), Fibrinogen

Why:
To determine whether one or more of your coagulation factors are increased, decreased or absent

When:
When you have unexplained or prolonged bleeding, an abnormal Prothrombin Time (PT) or Activated Partial Thromboplastin Time (aPTT) test, or have a relative with a hereditary coagulation factor deficiency; you may be tested when your doctor wants to monitor the severity of a factor deficiency and/or the effectiveness of treatment

Test General info:
Coagulation factors are a group of proteins essential for blood clot formation. When a patient has an unexplained bleeding episode, one possible cause is a reduction in the level of a coagulation factor in their blood. Measuring the level of these factors

Related Diseases:
Conditions: Hypercoagulable disorders, Bleeding disorders, Liver disease


Related Tests:
Bacterial wound culture, CSF analysis, Full blood count, Fungal infections, Susceptibility testing, Influenza tests, Urine culture

Why:
To check for the presence of a systemic infection

When:
When you have signs or symptoms of sepsis like fever, chills, feeling sick, confusion and tiredness which may develop during another illness, such as a urinary tract infection (UTI), pneumonia or a skin infection

Sample Type:
Two or more blood samples taken from separate sites (commonly from veins in your arms)

Test General info:
Blood cultures are done to detect and identify bacteria and yeasts (a type of fungus) in the blood. Some bacteria prefer oxygen (aerobes), while others thrive in a reduced oxygen environment (anaerobes). Blood cultures are usually collected into two types

Related Diseases:
Conditions:Fungal infections, Lung diseases, Meningitis, Septic arthritis, Urinary tract infection, Wound and skin infections, Sepsis


Other Names:
Peripheral blood smear, manual differential, red blood cell morphology

Related Tests:
FBC, differential, RBC, WBC, platelet count, reticulocyte count, haemoglobin, haemoglobin variants

Why:
To find out if red blood cells, white blood cells, and platelets are normal in appearance and number; to distinguish between different types of white blood cells and to determine their relative percentages in the blood; to help diagnose a range of deficie

When:
When FBC results are abnormal, a blood film with manual WBC differential is done to look for abnormal or immature cells; when a doctor suspects a deficiency, disease, or disorder that can affect blood cell production; when you are being treated for a disease with medications that may have an affect on blood cell production.

Sample Type:
A blood sample taken from a vein in your arm or by pricking a finger, ear or, in the case of an infant, a heel.

Test General info:
A blood film allows the evaluation of white blood cells (WBCs, leucocytes), red blood cells (RBCs, erythrocytes), and platelets (thrombocytes). These cell are produced and mature in the bone marrow and are released into the bloodstream when needed. WBCs’

Related Diseases:
Conditions: Anaemia, sickle cell anaemia, thalassaemia, leukaemia


Other Names:
Blood sugar; Fasting blood sugar; blood glucose; Oral Glucose Tolerance Test (OGTT or GTT); urine glucose

Related Tests:
Insulin, C-Peptide, Urine glucose, HbA1c, Microalbumin, Home Testing

Why:
To determine whether or not your blood glucose level is within normal ranges; to screen for, diagnose, and monitor diabetes, and hypoglycaemia (low blood glucose)

When:
If you have symptoms suggesting hyperglycaemia (high blood glucose) or hypoglycemia, or if you are pregnant; if you are diabetic, up to several times a day to monitor glucose levels

Sample Type:
A blood sample taken from a vein in your arm, or for a self check, a drop of blood from your finger. A few diabetic patients may use a continuous glucose monitor which is a small sensor wire inserted beneath the skin of the abdomen that measures blood glu

Test General info:
Glucose is a simple sugar that serves as the main source of energy for the body. The carbohydrates we eat are broken down into glucose (and a few other simple sugars), absorbed by the small intestine and circulated throughout the body. Most of the body`s


Why:
To screen for elevated concentrations of lead in your blood

When:
If you may have been exposed to lead where you live or work; children especially should be tested as they may have inhaled dust or ingested substances that could contain lead (e.g., from paint chips or water from lead pipes found in older housing). It is also important that pregnant women who think they may have been exposed also get tested due to the risk of maternal to fetal transfer of lead through the placenta.

Test General info:
The test measures the concentration of lead within the blood. Lead is a metal that is known to be poisonous. In the past, lead was used in paints, petrol, and other household products, which can still be found, for example, in older housing. Some work act


Formal Name:
Bone Marrow Aspiration; Bone Marrow Aspirate; Bone Marrow Biopsy; Bone Marrow Trephine Biopsy

Related Tests:
FBC, Differential, Reticulocyte count, Blood film, Haemoglobin, Haematocrit, Platelet count, WBC, RBC

Why:
To evaluate the type, quantity, and maturity levels of the cells present in the marrow; to evaluate the structure of the marrow; and sometimes to collect a sample of marrow for more specific testing

When:
When a patient is anaemic without an obvious cause and/or has a condition or cancer that may be affecting blood cell production; as a means of helping find out how advanced a cancer is; sometimes when a doctor is investigating a fever of unknown origin, especially when the patient is immuno-compromised

Sample Type:
A bone marrow sample collected primarily from the hip bone (pelvis); sometimes collected from the sternum (breast bone) in adults or the tibia (shin bone) in infants
The Test Sample

Test General info:
Bone marrow aspiration and biopsy are procedures used to collect and test bone marrow. Bone marrow is a soft fatty tissue found inside the body’s larger bones. It has a honeycomb or sponge-like structure, consisting of a network of fibers that is filled w

Related Diseases:
Conditions: Anaemia, Leukaemia, Bone Marrow Disorders, Myeloproliferative disorders, Lymphoma, Multiple Myeloma


Test Name:
Bordetella pertussis Antibodies, IgA, IgG, IgM

Formal Name:
Bordetella pertussis Culture; Bordetella pertussis by PCR; Bordetella pertussis by DFA; Bordetella pertussis Antibodies, IgA, IgG, IgM

Why:
To detect and diagnose a Bordetella pertussis infection

When:
When you have persistent, sharp spasms or fits of coughing (paroxysms) that the doctor suspects is due to pertussis (whooping cough); when you have symptoms of a cold and have been exposed to someone with pertussis

Sample Type:
A nasopharyngeal (NP) swab or a nasal aspirate; occasionally, a blood sample taken from a vein in your arm

Test General info:
This is a group of tests that are performed to detect and diagnose a Bordetella pertussis infection. B. pertussis is a bacterium that targets the lungs, typically causing a three-stage respiratory infection that is known as pertussis or whooping cough. It


Other Names:
Lyme disease antibodies by ELISA; Lyme disease antibodies by Western blot; Lyme disease bacterial DNA by PCR

Formal Name:
Borrelia burgdorferi IgM and IgG antibodies; Borrelia burgdorferi DNA by PCR

Why:
To see if you have been exposed to the bacterium that causes Lyme disease

When:
If you show symptoms of Lyme disease, especially if they appear some weeks after a painless bite from a small tick or you have recently been in woodland or long grass

Test General info:
Your blood is being tested for antibodies to the Lyme disease bacterium. Their presence means you have been infected with the Lyme disease spiral bacterium (spirochaete) known as Borrelia burgdorferi by a bite from an infected tick.
People bitten by an i


Test Name:
Borrelia burgdorferi IgM and IgG antibodies


Test Name:
Brain natriuretic peptide, NT-proBNP, N terminal pro B type natriuretic peptide, natriuretic peptides


Other Names:
BRCA; Breast Cancer Susceptibility Genes 1 and 2

Formal Name:
Breast Cancer Gene 1 and Breast Cancer Gene 2

Related Tests:
CA-125; CA 15-3; Her2/neu; Hormone Receptor Status; Tumour Markers

Why:
To assess the risk of developing breast and/or ovarian cancer

When:
If a BRCA1/2 mutation is present in a family member; if you have a very strong family history of breast and/or ovarian cancer; if you have had a breast cancer under the age of 35 that is hormone receptor negative

Test General info:
The genetic code of two genes; the BRCA-1 and BRCA-2 genes will be analysed in detail to look for alterations (mutations) that are linked with an inherited tendency to breast and ovarian cancers. Most cancers will not be explained by such an alteration, b

Related Diseases:
Conditions: Breast cancer, Ovarian cancer


Test Name:
Breast Cancer Gene 1 and Breast Cancer Gene 2


Test Name:
Breast Cancer Susceptibility Genes 1 and 2


Why:
To evaluate kidney function and monitor the effectiveness of dialysis

When:
If you have non-specific symptoms that may suggest a kidney problem or if you are suddenly ill or have a long term illness that may cause or be made worse by kidney disease

Test Prep:
No test preparation is required.
The Test

Test General info:
Urea is produced when protein is broken down by the body. Nitrogen in the form of ammonia is produced in the liver when protein is broken down. The nitrogen combines with other chemicals in the liver to form the waste product urea. The urea is released in


Formal Name:
Human epidermal growth factor receptor-2

Why:
To determine whether a cancer, usually a breast cancer, is positive for HER-2 gene amplification or protein expression, which helps to guide treatment and determine outcome. HER-2 evaluation is also used in the assessment of some other cancer types includ

When:
If you have been diagnosed with a cancer which may be responsive to treatment with HER-2 targetted therapy and your doctor wants to determine whether the HER-2 gene is amplified in the tumour.

Sample Type:
A sample of cancer tissue obtained during a biopsy. Generally this test is done on the biopsy taken for initial diagnosis and a second biopsy is not necessary. While HER-2 levels can be assessed in a blood sample, this is not usually done as treatment dec

Test General info:
HER-2 is an oncogene present in the nucleus of all cells. It encodes for a cell surface receptor of a chemical growth factor; when the growth factor binds to the receptor it becomes activated and this causes the cell to grow. Normal epithelial cells conta


When:
If you have type 1 or type 2 diabetes and your doctor wants to see if you are producing enough of your own insulin, if you are insulin resistant (when your body does not respond properly to insulin), or if it is time to add insulin injections to your current treatment. Your doctor also may request a C-peptide test if you have an episode of hypoglycaemia.

Sample Type:
A blood sample taken from a vein in your arm and sometimes a 24-hour urine sample is taken
The Test Sample

Test General info:
This test measures the level of C-peptide in a blood or urine sample. C-peptide and the hormone insulin are created from a larger molecule called proinsulin, and stored in the beta cells of the pancreas.  When insulin is released into the bloodstream to h

Related Diseases:
Tests: Insulin, glucose
Conditions: Diabetes, Kidney Disease, Liver Disease


Related Tests:
High-sensitivity C-reactive protein (hs-CRP); erythrocyte sedimentation rate (ESR)
Were you looking for the high-sensitivity CRP (hs-CRP) test, used to assess your risk of cardiovascular disease?

Why:
To identify the presence of inflammation, to determine its severity, and to monitor response to treatment.

When:
When your doctor suspects that you might be suffering from an inflammatory disorder (as with certain types of arthritis and autoimmune disorders or inflammatory bowel disease) or to check for the possibility of infection (especially after surgery)

Test General info:
C-reactive protein (CRP) is an acute phase reactant, a protein made by the liver that is released into the blood within a few hours after tissue injury, the start of an infection or other inflammation. Increased concentrations in the blood can be found af

Related Diseases:
Conditions: Arthritis, Autoimmune Disorders, Inflammatory Bowel Disease, Pelvic Inflammatory Disease, Systemic Lupus Erythematosus, Sepsis, Vasculitis, Meningitis and Encephalitis


Why:
To detect the presence of Clostridium difficile toxin

When:
When a patient has acute diarrhoea that persists for several days, abdominal pain, fever, and/or nausea following antibiotic therapy.

Sample Type:
A fresh stool sample that has not been contaminated with urine or water
The Test Sample

Test General info:
This test detects the presence of Clostridium difficile toxin A and/or B in a fresh or frozen stool sample. C. difficile is a bacterium that is present in the intestines of up to 70% of healthy infants and 5% of healthy adults. C. difficile is one of the

Related Diseases:
Tests: Stool Culture 
Conditions: Diarrhoea


Other Names:
C1; C1q; C2; C3; C4; Total Complement; CH50; CH100; Total Haemolytic Complement Activity; C1 esterase inhibitor

Formal Name:
Complement Activity; Complement Component C3; Complement Component C4

Why:
To determine whether complement system proteins are contributing to increased infections or autoimmune disease. To monitor the activity of certain autoimmune diseases. To help diagnose hereditary angioedema.

When:
When you have recurrent (usually bacterial) infections, unexplained episodes of swelling, or symptoms related to certain autoimmune disorders. Periodically to help monitor a known long term disease such as systemic lupus, that affects the complement system.

Test Prep:
No test preparation is needed for complement C3 and C4 measurements. For testing complement activity, the sample must be processed and frozen within 2 hours of the blood being taken from the patient.
The Test

Test General info:
Complement tests measure the quantity or activity of complement proteins in the blood. The complement system is composed of a set of circulating blood proteins that work together to promote protective immunity. Their principal role is to destroy bacteria

Related Diseases:
Conditions: Autoimmune Disorders, Systemic Lupus Erythematosus, Malnutrition, Vasculitis


When:
Before starting therapy for ovarian cancer or if at high risk for developing ovarian cancer, and at intervals during and after treatment. CA 125 may also be request by your GP if you have persistent or frequent symptoms that may be caused by ovarian cancer.

Test General info:
CA 125 is a protein often found on the surface of ovarian cancer cells and in some normal tissues. It is used as a marker for ovarian cancer. However, CA 125 levels may also be high in other types of non-cancerous conditions, including menstruation, pregn

Related Diseases:
Conditions: Ovarian cancer
News item: Ovarian cancer diagnosed following NICE recommendation for CA125 testing


When:
When you have been or are being treated for breast cancer

Test General info:
Cancer antigen 15-3 (CA 15-3) is a normal product of breast cells. Concentrations of CA 15-3 in the blood are often increased in breast cancer. CA 15-3 does not cause cancer; rather, it is a protein that is shed by the tumour cells, making it useful as a

Related Diseases:
Tests: Tumour Markers
Conditions: Breast cancer


Why:
To monitor the response to treatment of breast cancer and to watch for recurrence of the disease


Related Tests:
Bilirubin, CEA, Liver Function Tests, Tumour Markers

Why:
To help tell the difference between cancer of the pancreas and bile ducts and other conditions; to monitor response to pancreatic cancer treatment and to watch for recurrence.

When:
When your doctor suspects that you have pancreatic cancer and during or following pancreatic cancer treatment.

Test General info:
Cancer antigen 19-9 (CA 19-9) is a protein that exists on the surface of certain cells. CA 19-9 does not cause cancer; rather, it is a protein that is produced by the tumour cells, making it useful as a tumour marker to follow the course of the cancer.

Related Diseases:
Tests: Tumour Markers
Conditions: Pancreatic Cancer, Pancreatitis


Why:
To measure the amount of caeruloplasmin in the blood; to help diagnose Wilson’s disease; sometimes to help identify conditions associated with copper deficiencies

When:
When you have jaundice, tiredness, tummy pain, behavioural changes, tremors, or other symptoms that your doctor thinks may be due to Wilson’s disease or, rarely, to copper deficiency. At intervals when monitoring a copper related disease or its treatment.


Related Tests:
Creatinine; creatinine clearance; microalbumin; cystatin c; urine protein

Why:
In the UK, the National Institute for Health and Care Excellence (NICE) guidance (CG73) states: “Whenever a request for serum creatinine measurement is made, clinical laboratories should report an estimate of GFR (eGFR)”

When:
As a practical test to look for evidence of kidney damage. For a more definitive assessment of kidney function or to monitor changes in kidney function if you already have kidney disease, measurement of creatinine clearance is preferred.

Sample Type:
eGFR is an estimate of actual glomerular filtration rate, calculated using your age, weight, gender, and serum creatinine (requires a blood sample from a vein in your arm); in some formulas, race is also used in the calculation. Measured Creatinine Cleara

Test General info:
Glomerular filtration rate (GFR) is a measure of the function of your kidneys. Glomeruli are tiny filters in your kidney that allow waste products to be removed from the blood, while preventing loss of important proteins and blood cells. The rate refers t

Related Diseases:
Conditions: Kidney disease, Diabetes, Hypertension


When:
If your doctor suspects that you have MTC, if you are being treated for MTC, or if a family member has MTC or MEN 2

Test Prep:
It is important that the person taking the sample follows the instructions of the local laboratory as different laboratories may require different specimen types. Please contact the local laboratory for details.
The Test

Test General info:
This test measures the amount of calcitonin in the blood. The function of calcitonin in the human body is unknown; what is known is that it is a hormone produced by C-cells in the thyroid. The thyroid is a small butterfly-shaped gland that lies over and f


When:
In persons with kidney, bone, or nerve disease, or when symptoms of abnormal calcium are present.

Sample Type:
A blood sample taken from a vein in your arm; a timed urine collection may be used when blood calcium is abnormal; urine calcium measurements may also be requested if you have kidney stones

Test Prep:
Current practices do not require fasting or any other test preparation.
The Test

Test General info:
Calcium is one of the most important minerals in the body. About 99% of it is found in the bones, and most of the rest circulates in the blood. Roughly half of the calcium is referred to as `free` (or `ionized`), and is active within the body; the remaini

Related Diseases:
Conditions: Kidney disease; thyroid disease; breast cancer; multiple myeloma; alcoholism


Related Tests:
Phosphate, Vitamin D, Parathyroid Hormone (PTH), albumin

Why:
To determine if the concentration of calcium in your blood is at normal levels.


Other Names:
Urinary Stone Analysis; Calculus Analysis; Renal Stone Analysis

Related Tests:
Urinalysis; Uric Acid; Calcium; Phosphate; Creatinine; Oxalate; Citrate; Cystine

Why:
To evaluate the composition of a kidney stone, to help determine the cause of its formation and to guide treatment

When:
A stone can be analysed either after a surgeon has removed it from your urinary tract or if you catch a stone that has come out of your urinary tract when passing urine

Sample Type:
A stone filtered from your urine or surgically removed from your urinary tract by a doctor

Test General info:
Kidney stone analysis uses one or more test methods to examine and determine the composition of a stone from the urinary tract. This is done in order to help identify the cause of the stone and, where possible, to prevent the formation of more stones.
Th

Related Diseases:
Conditions: Kidney Disease, Urinary Tract Infection, Gout


Related Tests:
Phenytoin, Therapeutic Drug Monitoring, Valproic acid

Why:
To determine the concentration of carbamazepine in the blood to establish an appropriate dose and to maintain a therapeutic level

When:
At the beginning of treatment to monitor the concentration of the drug in the blood. When indicated to detect low or high (potentially toxic) concentrations

Test General info:
This test measures the amount of carbamazepine in the blood. Carbamazepine is a drug that is primarily used to treat certain seizure disorders (also called epilepsy), but is also prescribed to stabilize the moods of patients with bipolar disease and to he


Related Tests:
Tumour Markers, CA 19-9, AFP Tumour Marker

Why:
In the presence of certain cancers, CEA may be used to monitor the effect of treatment and recurrence of disease

When:
Before starting cancer treatment as well as at intervals during and after therapy

Test General info:
CEA is a protein that is normally not detected in the blood of a healthy person. When certain types of cancer are present, CEA may be produced by the cancer cells. CEA may then be detected in blood, but it will not indicate which kind of cancer is present

Related Diseases:
Conditions: Bowel Cancer, Pancreatic Cancer, Ovarian Cancer, Breast Cancer


Formal Name:
Cardiac-specific Troponins I and T (cTnI and cTnT); High-sensitivity cardiac-specific Troponins I and T (hs-cTnI and hs-cTnT)

Why:
To see if you have had a heart attack or damage to your heart muscle

When:
If you are having chest pain that may be due to a heart attack.

Test General info:
Troponins are proteins in muscle fibres that help to regulate muscle contraction. There are three different troponins: skeletal muscle troponin C (TnC) and two heart muscle troponins, cardiac troponin T (cTnT) and cardiac troponin I (cTnI). When there is

Related Diseases:
Tests: Cardiac Risk Assessment
Conditions: Heart attack, Cardiovascular Disease


Test Name:
Cardiolipin Antibodies, IgG, IgM, and IgA


Other Names:
T4 count; T-helper cells; T-suppressor cells; cytotoxic T-cells

Formal Name:
CD4 lymphocyte count; CD8 lymphocyte count; T-cell subsets; CD4/CD8 ratio; CD4 percent

Related Tests:
HIV antibody, p24 antigen test, HIV viral load, HIV genotypic resistance testing, HIV phenotypic resistance testing

Why:
Most often, this test is done to measure the strength of your immune system if you’ve been diagnosed with HIV infection.  Occasionally it may be used with other conditions.

When:
If you’ve been diagnosed with HIV, soon after you are first diagnosed to get a baseline assessment of your immune system; 2-8 weeks after starting anti-HIV therapy and then every three to four months if you continue therapy

Test General info:
CD4 and CD8 cells are lymphocytes that have markers on the surfaces of the cells called CD4 and CD8. They are types of white blood cells that fight infection, and they play an important role in your immune system function.  CD4 and CD8 cells are made in t


Related Tests:
Glucose; Total Protein; FBC (Full Blood Count); Lactate; Protein Electrophoresis;  AFB Smear and Culture; Blood Culture; Herpes; Lyme Disease; Rubella; Syphilis; West Nile Virus

Why:
To diagnose a disease or condition affecting the central nervous system (CNS) such as bleeding within the brain or skull, cancer, autoimmune disorder or infection

When:
When your doctor suspects that your symptoms are due to a condition or disease involving your central nervous system

Sample Type:
A sample of cerebrospinal fluid (CSF) is collected by a doctor from the lower back using a procedure called a lumbar puncture or spinal tap

Test Prep:
The patient should empty their bladder and bowels prior to the sample collection. It will be necessary to lie still in a curled-up fetal position during the test and to lie quietly for a time period after the collection.
The Test

Test General info:
Cerebrospinal fluid (CSF) is a clear watery liquid filtrate that is formed by the choroid plexus, special tissue that has many blood vessels and lines the small spaces or chambers (ventricles) in the brain. CSF flows around the brain and spinal cord, surr

Related Diseases:
Conditions: Meningitis and Encephalitis, Guillain-Barre syndrome, Herpes, HIV, Lyme disease, Multiple sclerosis, Syphilis, Traveller’s diseases, Tuberculosis, West Nile Virus


Other Names:
Cervical screening test; Liquid based cytology test (LBC)

Formal Name:
Smear Test; PAP Test; Papanicolaou smear; cervical/vaginal cytology

Related Tests:
Human Papillomavirus (HPV), Trichomonas wet prep

Why:
To screen for early abnormalities (pre-cancer) which, if left untreated, could lead to cervical cancer.

When:
In England, all woman between the ages of 25 and 64 are eligible for a free cervical screening test every three to five years, depending on age.
In Wales those between 20 and 64 are eligible for screening at 3 yearly intervals.
In Scotland those between 20 and 60 are eligible for screening 3 at yearly intervals.
In Northern Ireland those between 20 and 64 are eligible for screening at 5 yearly intervals.
In the Republic of Ireland those between 25 and 44 are eligible for screening at 3 yearly intervals and those between 45 and 60 at 5 yearly intervals.

Sample Type:
Cells from the cervix (neck of the womb)

Test Prep:
You may be asked to refrain from sexual intercourse for 24-48 hours before the test, avoid using vaginal creams or foams in the 48 hours before the test and book the test appointment 10-14 days after the beginning of your last menstrual period.
The Test

Test General info:
A cervical cytology test is a test used to detect abnormal or potentially abnormal cells from the uterine cervix (neck of the womb).


Other Names:
Cystic fibrosis (CF) genotyping; CF DNA analysis; CF gene mutation panel; molecular genetic testing

Related Tests:
Sweat chloride, Immunoreactive trypsin (IRT)

Why:
To detect cystic fibrosis (CF) genetic mutations to establish CF carrier status or to establish the diagnosis of CF in an individual

When:
When a newborn baby has no stools in the first 24 to 48 hours of life (meconium ileus) or when a person has symptoms of CF; if a person has a positive sweat chloride or an immunoreactive trypsin test or a close relative who has been diagnosed with CF; or when a patient is undergoing genetic counselling and wants to find out if they are a CF carrier. In addition, high risk carrier couples may have the test prior to in vitro fertilization so that the test can be carried out before implantation.

Sample Type:
A blood sample taken from an infant`s heel; a spot of blood that is put onto filter paper; or a blood sample taken from a vein in the arm
The Test Sample

Test General info:
The CF gene mutation test identifies mutations in the CFTR gene. Each cell in the human body (except sperm and eggs) has 46 chromosomes (23 inherited from the mother and 23 from the father). Genes on these chromosomes form the body`s blueprint for produci

Related Diseases:
Conditions: Cystic fibrosis, Lung diseases


Related Tests:
Serotonin, 5-HIAA, Catecholamines, Tumour Markers

Why:
To help diagnose and monitor carcinoid tumours and other neuroendocrine tumours

When:
When you have symptoms suggestive of a carcinoid tumour such as flushing, diarrhoea, and/or wheezing. When your doctor thinks you may have a carcinoid or other neuroendocrine tumour

Test Prep:
You may be required to fast overnight prior to the specimen being taken and to temporarily discontinue certain medication beforehand. Please check the local laboratory instructions with your doctor prior to blood being taken.
The Test

Test General info:
This test measures the amount of Chromogranin A (CgA) in the blood. CgA is a protein found in and released from neuroendocrine cells. Neuroendocrine cells, and the endocrine system glands that they are found in, can give rise to a variety of tumours, both

Related Diseases:
Tests: Serotonin, 5-HIAA, Catecholamines, Tumour Markers


Other Names:
Varicella Zoster Virus (VZV); Herpes Zoster

Formal Name:
Varicella Zoster Virus Culture; Varicella Zoster Virus by PCR; Varicella Zoster Virus by DFA; Varicella Zoster Virus Antibodies; IgG and IgM

Why:
If your doctor suspects that you have, or have recently had, chickenpox or shingles and a diagnosis is necessary; to show immunity to the varicella zoster virus (VZV) or the potential for re-activating a VZV infection before receiving immunosuppressive dr

When:
To check immune status and/or to find an active infection; sometimes when a person has unusual (atypical) and/or severe symptoms and the doctor wants to distinguish between a VZV infection and another cause; prior to an organ transplant or when pregnant woman, or an immune-compromised person has been exposed to someone with chickenpox

Sample Type:
A blood sample is taken from a vein in your arm for VZV antibody testing; to detect the virus itself, a sample of fluid from a blister (vesicle), blood, cerebrospinal fluid, or other body fluid or tissue

Test General info:
Tests for chicken pox and shingles are done to find and diagnose either a current or past infection with the virus (varicella zoster virus (VZV)) that causes these conditions. Most often, testing is not necessary because a diagnosis of active infection ca


Why:
To screen for or diagnose chlamydia infection

When:
If you are sexually active and have one or more risk factors for developing chlamydia, or have symptoms of infection e.g. discharge from the vagina or penis.

Sample Type:
A urine sample or a swab of cells or secretion from the infected area is required
The Test Sample

Test General info:
The test is looking for evidence of infection by the bacterium Chlamydia trachomatis, the most common bacterial sexually transmitted disease (STD) in the United Kingdom.


When:
If your doctor thinks that you have an electrolyte imbalance

Sample Type:
A blood sample taken from a vein in the arm or a urine sample

Test General info:
Chloride is an electrolyte. When combined with sodium it is mostly found in nature as “salt.” Chloride is important in maintaining the normal acid-base balance of the body and, along with sodium, in keeping normal levels of water in the body. Chloride gen

Related Diseases:
Conditions: Acidosis and Alkalosis, Addison`s Disease, Cushing Syndrome, Hypertension, Congestive Heart Failure, Lung Diseases, Kidney Disease, Diarrhoea


Why:
To determine if there is a problem with your body’s acid-alkali (pH) balance and to monitor treatment


Related Tests:
Therapeutic drug monitoring, urea, Creatinine, Lipid profile, Liver function tests

Why:
To determine the concentration of ciclosporin in your blood in order to establish a dose regime, maintain therapeutic levels, and detect toxic levels

When:
As soon as ciclosporin therapy begins, usually daily or 2-3 times a week, and periodically after that as dose is adjusted or maintained

Test General info:
This test measures the amount of ciclosporin in the blood. Ciclosporin is an immunosuppressive drug used to dampen the body’s natural defences. When patients have an organ transplant, their immune system recognizes the new organ as a foreign substance and

Related Diseases:
Conditions: Autoimmune disorders, Inflammatory bowel disease, Rheumatoid arthritis


Why:
To detect and monitor muscle damage and to help diagnose conditions associated with muscle damage

When:
If you have muscle pain, tenderness, weakness and swelling after muscle damage, particularly if your urine becomes dark reddish-brown in colour

Test General info:
This test measures the amount of creatine kinase (CK) in the blood. CK is an enzyme found in the heart, brain, skeletal muscle and other tissues. Increased amounts are released into the bloodstream when there is muscle damage. CK occurs in three major for


Why:
To find out if you have had a heart attack

When:
If you have chest pain and troponin test is not available

Test General info:
Creatine kinase (CK) is an enzyme that occurs in three major forms, called isoenzymes:
CK-MB (found mostly in heart muscle) 
CK-BB (found mostly in brain) 
CK-MM (found in muscles) 
CK–MB rises when there is any damage to heart muscle cells.


Related Tests:
Epstein Barr Virus (EBV); Herpes Simplex Virus; Varicella Zoster Virus (VZV); TORCH

Why:
If your doctor suspects you presently have, or recently had, a cytomegalovirus (CMV) infection or if it is important to know if you have ever had a CMV infection – such as prior to receiving an organ transplant

When:
When a young adult, a pregnant female, or an immune-compromised patient has typical symptoms that suggest a CMV infection (tiredness, fever, jaundice); when a newborn has multiple congenital anomalies, unexplained jaundice or anaemia, and/or when an infant has seizures or developmental problems that may be due to CMV

Sample Type:
A blood sample taken from a vein in your arm for CMV antibody testing; to detect the virus itself, sample may be blood, urine, or sputum, amniotic fluid, cerebrospinal fluid (CSF), duodenal fluid, or other body tissue

Test General info:
Cytomegalovirus (CMV) testing is requested to determine whether someone is currently, or has recently been, infected with CMV. It may also sometimes be used to determine whether someone has ever been exposed to CMV. Testing for CMV involves either a measu


Related Tests:
FBC, ESR, CRP, Calcium, Total Protein, Albumin, Vitamin D, Vitamin B12, Vitamin E, Iron, Folate, Anti-Endomysial Antibodies (EMA), Anti-tissue Transglutaminase Antibody (TTG)

Why:
To help in making a diagnosis of coeliac disease, and also to assess the effectiveness and degree of adherence to a gluten-free diet

When:
Patients who have symptoms suggestive of coeliac disease should be tested. These symptoms may include, for example:
chronic diarrhoea 
abdominal pain 
weight loss 
anaemia 
poor growth or chronic irritability in an infant or child 
Patients with known coeliac disease may be tested by their doctor to help assess the effectiveness and observance of a gluten-free diet.

Test Prep:
Follow your doctor`s instructions. For diagnosis, ingestion of gluten-containing foods for a time period, such as several weeks, is necessary. For monitoring, no preparation is necessary.
The Test

Test General info:
Coeliac antibody tests help in the diagnosis of coeliac disease, and also can help to rule out this diagnosis. These tests detect autoantibodies that the body creates as part of an immune response to dietary proteins (such as gluten) found in wheat, rye,

Related Diseases:
Conditions: Coeliac disease, Autoimmune disorders, Malnutrition


Why:
To help detect and to monitor prostate cancer

When:
If you have symptoms of prostate disease, such as difficulty in passing urine, or passing urine more frequently than usual

Test General info:
Blood is being tested for the level of PSA it contains. PSA is a protein produced mainly by cells in the prostate gland and can be a useful indicator of prostate cancer. This protein can be found in all males; however, men whose levels are increased may h

Related Diseases:
For more information visit the Macmillan cancer support website.
^ Back to top2.  Are the recommendations for PSA testing different for different ethnic groups, such as those of Afro-Caribbean descent? 
The incidence for disease is greater among Afro-Ca


When:
When you have jaundice, fatigue, abdominal pain, behavioural changes, tremor, or other symptoms that your doctor thinks may be due to Wilson’s disease or, rarely, to copper deficiency or excess; at intervals when you are being treated for a copper-related condition

Sample Type:
A blood sample taken from a vein in your arm and/or a 24-hour urine sample; sometimes a liver biopsy sample

Test General info:
This test measures the amount of copper in the blood, urine, or liver (hepatic). Copper is an essential mineral that the body incorporates into enzymes. These enzymes play a role in the regulation of iron metabolism, formation of connective tissue, energy


Other Names:
Retic Count; Reticulocyte Index; Corrected Reticulocyte

Related Tests:
Red blood cell count; Haemoglobin; Haematocrit; FBC; Blood film; Erythropoietin

Why:
To help evaluate the bone marrow`s ability to produce red blood cells (RBCs) and to help distinguish between anaemia related to blood loss or destruction and anaemia related to decreased RBC production; to help monitor bone marrow response and the return

When:
When you have a decreased (or increased) RBC count, haemoglobin, and haematocrit and your doctor wants to evaluate bone marrow function

Sample Type:
A blood sample obtained by inserting a needle into a vein in the arm or sometimes from pricking a finger or the heel of an infant

Test General info:
Reticulocytes are immature red blood cells (RBCs). They are produced in the bone marrow when stem cells differentiate and progress toward RBC development, eventually forming reticulocytes and finally mature RBCs. Most RBCs are fully mature before they are

Related Diseases:
Conditions: Anaemia, Bone marrow disorders


Other Names:
Serum Cortisol, Urine Cortisol, Urinary Free Cortisol, Salivary Cortisol

Related Tests:
ACTH, Aldosterone, Synacthen stimulation test, Dexamethasone Suppression Test

Why:
To help diagnose Cushing’s syndrome or Addison’s disease (primary adrenal insufficiency) or secondary adrenal insufficiency.

When:
If your doctor suspects damage to the adrenal gland, or any condition that could result in the body producing too much cortisol

Sample Type:
A blood sample taken from a vein in the arm or a 24 hour urine sample. Occasionally a saliva sample may be tested.

Test Prep:
Some test preparation may be needed. Follow any doctor’s instructions that are given as far as timing of sample collection, resting, and/or any other specific pre-test preparation.
A saliva test requires special care in obtaining the sample. You may be i

Test General info:
Cortisol is a steroid hormone, produced by the adrenal gland, which is essential for survival. Production and secretion of cortisol is stimulated by ACTH (adrenocorticotropic hormone), a hormone produced by the pituitary gland – a tiny organ located insid

Related Diseases:
Conditions: Cushing`s syndrome, Addison`s Disease


When:
As part of a routine blood test if you have non-specific health complaints or if your doctor thinks that you may have kidney disease; at intervals to monitor treatment for kidney disease or kidney function while on certain medicines

Sample Type:
A blood sample taken from a vein in the arm and/or a 24-hour urine sample

Test General info:
This test measures the amount of creatinine in your blood and/or urine. Creatinine is a waste product produced in your muscles from the breakdown of a compound called creatine. Creatine is part of the cycle that produces energy needed to contract your mus

Related Diseases:
Conditions: Congestive heart failure, diabetes, kidney disease


Related Tests:
Creatinine; glomerular filtration rate (GFR); Urinalysis

Why:
To help detect and evaluate kidney dysfunction or decreased blood flow to the kidneys

When:
If your doctor thinks that you may have a problem affecting the function of your kidneys, such as an obstruction within the kidney, acute or chronic kidney failure, dehydration, shock, or another disease, such as congestive heart failure. Creatinine clearance may also be measured before you are prescribed certain drugs which rely on good kidney function in order to allow the drugs to be removed from the body effectively after they have carried out their purpose. Other straightforward methods of estimating the function of your kidneys now in routine use across the UK include the calculation of estimated glomerular function rate (eGFR) from a single blood sample taken from a vein in your arm.

Sample Type:
Both a urine sample (24-hour collection) and a blood sample taken from a vein in your arm.

Test General info:
This test measures the concentration of creatinine in both a sample of blood and a sample of urine from a 24-hour urine collection. The results are used to calculate the amount of creatinine that has been cleared from the blood and passed into the urine.

Related Diseases:
Conditions: Congestive heart failure, kidney disease


Other Names:
Fragment D-dimer; Cross-linked fibrin degradation product (XDP)

Related Tests:
Fibrin Degradation Product (FDP); Prothrombin Time (PT); Partial Thromboplastin Time (aPTT, or PTT); Fibrinogen; Platelet Count

Why:
To help diagnose or exclude thrombotic (blood clot producing) or bleeding diseases and conditions.

When:
When you have symptoms of a disease or condition that causes acute and/or chronic inappropriate blood clot formation such as: DVT (Deep Vein Thrombosis), PE (Pulmonary Embolism), or DIC (Disseminated Intravascular Coagulation), and to monitor the progress and treatment of DIC and other thrombotic conditions.

Test General info:
When a vein or artery is injured and begins to leak blood, a sequence of clotting steps and factors (called the coagulation cascade) is activated by the body to limit bleeding and create a blood clot to plug the hole.  During this process, threads of a pr


Related Tests:
Lipid profile; Cardiac risk assessment; CRP
Were you looking for the CRP test, used to evaluate general inflammation?

Why:
May be used to predict your risk of developing heart disease

When:
When risk factors for heart and blood vessel disease are present as part of cardiac risk assessment; currently most testing is done in research settings only

Test General info:
C-reactive protein (CRP) is a protein in the blood that increases when inflammation is present. CRP has been used for many years as an indicator of infection and inflammation associated with disease. Doctors now believe that atherosclerosis (fatty build-u


Related Tests:
Protein Electrophoresis; Hepatitis C, Complement C4 levels, rheumatoid factor

Why:
To determine if symptoms like sensitivity of extremities to cold is due to the presence of abnormal proteins called cryoglobulins in the blood

When:
When a person has symptoms such as a rash, bruising, pain, weakness, joint pain, and/or paleness and coolness of the extremities that occur at cold temperatures

Test General info:
This test detects and measures the relative quantity of cryoglobulins in the blood. Cryoglobulins are circulating proteins, specifically, immunoglobulins, (i.e., IgG, IgM, IgA) that clump together (precipitate) when they are exposed to cold and dissolve w

Related Diseases:
Conditions: Systemic Lupus Erythematosus, Autoimmune Disorders, Hepatitis, Multiple Myeloma, Lymphoma, Leukaemia, RA


Other Names:
Cu, 24-hour urine copper; Total copper; Non-caeruloplasmin-bound copper; Free copper; Hepatic copper

Formal Name:
Copper (24-hour urine, total and free blood, and hepatic)

Why:
To measure the amount of copper in the blood, urine, or liver; to help diagnose and monitor Wilson’s disease; sometimes to identify copper deficiencies and excesses


Why:
To diagnose a urinary tract infection (UTI)

When:
If you experience symptoms of a UTI, such as pain during urination

Sample Type:
A mid-stream ``clean`` urine sample
The Test Sample

Test General info:
Urine is one of the body’s waste products. It is produced in the kidneys and collected in the bladder until a person urinates. Normally, the urine does not contain significant numbers of any microorganism. However, if bacteria or yeast are introduced into


Related Tests:
Gram Stain, Susceptibility Testing, AFB Smear and Culture, Blood Culture, Fungal Tests, FBC

Why:
To detect and identify the cause of bacterial pneumonia and other lower respiratory tract infections; to monitor the effectiveness of treatment

When:
When you have symptoms associated with a lower respiratory tract infection; when you have been treated for bacterial pneumonia

Sample Type:
A fresh sputum sample (deep respiratory secretions, not saliva), usually collected first thing in the morning

Test Prep:
Rinse mouth out with water prior to collection to remove loose cells in the oral cavity.
The Test

Test General info:
Sputum cultures detect the presence of disease-causing bacteria in those who have bacterial pneumonia and other lower respiratory tract infections. Bacteria in the sample are identified and their susceptibility to various antibiotics is assessed to help c

Related Diseases:
Conditions:Pneumonia, Lung Diseases, Tuberculosis, Nontuberculous Mycobacteria, Fungal Infections, Cystic Fibrosis


Related Tests:
Creatinine, Creatinine Clearance, Calculated Creatinine Clearance, urea, Estimated Glomerular Filtration Rate (eGFR)

Why:
Currently not routinely available but in the future, may serve as an alternative to creatinine to monitor kidney function in those with known or suspected kidney diseases

When:
It may prove useful if you have symptoms of kidney disease and/or have a disease or condition that is known to affect kidney function

Test General info:
Cystatin C is a small protein that is produced by nucleated cells. It is produced and destroyed at a constant rate and is found in a variety of body fluids such as blood, spinal fluid, and breast milk. 

Cystatin C is filtered out of the blood by the gl


Related Tests:
Stool Culture; Giardia; Cryptosporidium; Entamoeba Histolytica antigen tests

Why:
To determine whether you have a parasite infecting your gastrointestinal tract.

When:
When you have diarrhoea that lasts more than a few days and/or have blood or mucous in your loose stools, especially if you have drunk stream or lake water while camping or have travelled outside of the United Kingdom.

Sample Type:
A fresh or preserved stool sample, sometimes multiple samples collected on different days.
The Test Sample

Test General info:
An ova, cysts and parasite (OCP) exam is a microscopic evaluation of a stool sample. It is used to look for parasites that have infected the gastrointestinal tract. These parasites and their ova (eggs, cyst form) are shed - passed out of the body through


Why:
To help evaluate your ability to absorb carbohydrates

When:
When you have symptoms of malabsorption, such as persistent diarrhoea and fatty stools

Sample Type:
Timed blood samples drawn from a vein in your arm and a timed urine collection

Test Prep:
Fast for 8 hours and avoid foods high in pentose, such as jams, fruits, and pastries, for 24 hours prior to the test. Ask your doctor if there are any necessary medication changes.
The Test

Test General info:
D-Xylose is a simple sugar (carbohydrate) that is usually easily absorbed by the intestines. This test determines how well someone absorbs D-xylose, in order to evaluate the person`s ability to absorb carbohydrates in general. This is done by measuring th

Related Diseases:
Conditions: Malabsorption, Diarrhoea, Cystic Fibrosis, Coeliac Disease, Pancreatic Insufficiency, Malnutrition


Related Tests:
Testosterone; ACTH; FSH; LH; Prolactin; Oestrogen; Sex hormone binding globulin (SHBG); 17-Hydroxyprogesterone

Why:
DHEAS is measured to evaluate adrenal function and certain adrenal tumours, and to investigate the cause of virilisation in girls or early puberty in boys.

When:
The measurement of DHEAS is used very infrequently in the UK as it has been found that other tests are more helpful.  A doctor may measure DHEAS in a woman who has excess facial and body hair (hirsutism), acne, amenorrhea, or infertility; and more rarely in a male child who is undergoing very early (precocious) puberty or a female child who is showing signs of virilisation. 

It is sometimes used in the investigation of Cushing’s syndrome to help differentiate an adrenal tumour from adrenal carcinoma.

Test General info:
Dehydroepiandrosterone Sulphate (DHEAS) is a weak androgen, a male sex hormone, that is present in the blood of both men and women. It has a role to play in developing male secondary sexual characteristics at puberty, and it can be changed by the body int


Other Names:
Differential leucocyte count; White blood cell morphology; WBC differential; Diff

Why:
To diagnose an illness affecting your immune system, such as an infection, inflammatory illness, immune deficiency, or tumour such as leukaemia or lymphoma

When:
As part of a full blood count (FBC), which may be requested for a variety of reasons

Sample Type:
A blood sample taken from a vein in your arm or by a finger-prick (children and adults) or heel-prick (infants)

Test General info:
There are five types of white blood cells, each with different functions: neutrophils, lymphocytes, monocytes, eosinophils and basophils. The differential reveals if these cells are present in normal proportion to one another, if one cell type is increase


Related Tests:
Therapeutic drug monitoring; Urea; Creatinine; Creatinine clearance; Potassium

Why:
To determine if the amount of digoxin in your blood is at an appropriate level or to detect potentially toxic levels

When:
Soon after the start of digoxin therapy and at regular intervals to ensure that drug levels are within the desired range and are not low or at toxic concentrations

Sample Type:
A blood sample collected from a vein in your arm

Test Prep:
No special preparation is needed, but timing of the sample for testing is important. When you have your blood taken, tell the blood collector when you took your last dose of digoxin. You may want to write down the exact time at which you took your dose an

Test General info:
Digoxin is a drug used to treat heart failure and abnormal heart rhythms. This test measures the amount of digoxin in the blood. Heart failure, including congestive heart failure (CHF) causes the heart to become less effective at circulating blood. As a r

Related Diseases:
Conditions: Heart attack, Heart disease, CHF, Hypertension, Kidney disease


Related Tests:
LDL; Lipid Profile; Cholesterol; HDL; Triglycerides; ApoB

Why:
To help determine your risk of developing heart disease and to monitor lipid-lowering lifestyle changes and drug therapies; to accurately determine your low-density lipoprotein cholesterol (LDL-C) concentration when you have raised triglyceride concentrat

When:
As a follow-up to a lipid profile if your triglycerides are significantly elevated; at regular intervals to monitor efforts to lower LDL concentrations

Test Prep:
No test preparation is needed. Your doctor might recommend that you fast (water only) for 14 hours prior to the test, so that other related substances can be measured in the same sample.
The Test

Test General info:
The direct low-density lipoprotein cholesterol test (direct LDL-C) measures the amount of LDL cholesterol, sometimes called “bad” cholesterol, in the blood. Elevated concentrations are associated with increased risk of atherosclerosis and heart disease. U


Other Names:
Hydrogen Breath Test; Lactose Breath Test; Disaccharide Absorption Test; Oral Lactose Tolerance

Formal Name:
Hydrogen Breath Test; Lactose Tolerance Test

Related Tests:
Stool Acidity Test, Glucose, Xylose Absorption Test, Coeliac Disease Tests

Why:
To help diagnose lactose intolerance in individuals who have difficulties digesting dairy products, or sometimes as part of an investigation of malabsorption conditions

When:
When you have symptoms such as abdominal pain, bloating, gas, and diarrhoea after consuming milk and other dairy products

Sample Type:
A series of breath samples exhaled into a collector, or a series of blood samples drawn from a vein in your arm

Test Prep:
Fasting is required before and during testing. The person being tested should not exercise or smoke for several hours before testing. In some cases, additional instructions may be provided by the doctor and/or laboratory. For example, you may be asked to

Test General info:
Lactose tolerance tests measure hydrogen in the breath or changes in the level of glucose in the blood after a person is given a drink containing a standard amount of lactose, thus determining whether the individual is capable of proper digestion of lacto

Related Diseases:
Conditions: Lactose Intolerance, Malabsorption, Coeliac Disease, Diarrhoea, Pancreatic Insufficiency


Other Names:
Drug testing; Drug screen; Poison testing; Toxicology assays

Related Tests:
Drugs of abuse; Osmolality; Therapeutic drug monitoring; Electrolytes; Glucose; Urea; Creatinine; Liver Function; Blood gases; Paracetamol; Ethanol; Salicylate

Why:
To detect, measure, and occasionally monitor drugs that are causing acute overdose symptoms; results from emergency and overdose testing are used mainly for to help treatment. If results are needed for legal proceedings, then special legal (forensic) proc

When:
When a person has symptoms such confusion, difficulty breathing, feeling sick, agitation, fits, changes in heart rhythm, or increased temperature that the Accident and Emergency (A&E) doctor thinks may be drug-related; at intervals to monitor a drug overdose

Sample Type:
A blood sample taken from a vein in your arm, a urine sample, or sometimes a breath sample; rarely, saliva or another body fluid

Test General info:
Emergency and overdose drug testing is requested for single drugs or groups of drugs by an A&E or Intensive Care doctor to detect, assess, and monitor someone who has a drug overdose. A drug overdose may be caused by a variety of prescription and over-the


Why:
To detect or exclude the presence of abused and/or illegal drugs. This may be carried out for a number of reasons including a pre-employment screen or to comply with a drug rehabilitation programme.

When:
If you apply for a job where drug screens are carried out as a routine. People with drug and alcohol problems have worse record for accidents and absenteeism; for this reason some employers screen  job applicants prior to appointment. 
If you have admitted having a drug problem and are enrolled in a detoxification or drug rehabilitation scheme. 
If you believe you may have taken a drug accidentally or been given a drug without consent (e.g. drink spiking). 
If you are admitted to hospital in an emergency and doctors think that your treatment could be improved if drug abuse could be proved or excluded. 
If you take part in a sport at a professional level. 
If you apply for an insurance policy – some companies perform limited drug screening on applicants. 
For legal reasons (e.g. child custody cases).

Sample Type:
A random urine sample is usually collected for detection of drugs of abuse although they can be detected in blood, sweat, saliva, mother`s milk and hair samples.
The Test Sample

Test General info:
The presence of various classes of abused drugs can be tested for. This usually starts with a screen where the drug group (e.g. opiates) is detected; positive results are then followed up by a more specific test which identifies the individual drug taken


Other Names:
E. coli; E. coli O157; E. coli non-O157; STEC

Formal Name:
E. coli O157 culture; Shiga-like toxin by EIA; Stx gene detection by PCR

Why:
To determine if your gastrointestinal symptoms are due to an infection caused by Escherichia coli bacteria that produce Shiga toxin

When:
When you have acute diarrhoea that is persistent, severe and/or bloody

Sample Type:
A fresh liquid or unformed stool sample that does not contain urine or water, collected in a clean dry container; a rectal swab may be collected from infants. Stool and rectal swab may be placed in transport media for delivery to laboratory.

Test General info:
These tests detect the presence of disease-causing (pathogenic) Escherichia coli that produce Shiga toxins. E. coli bacteria commonly occur in nature and they are a necessary component of the digestive process in humans and most other mammals. Most strain


Other Names:
EBV Antibodies; EBV VCA-IgM Ab; EBV VCA-IgG Ab; EBNA-IgG Ab; EA-D IgG Ab

Formal Name:
Epstein-Barr Virus Antibody to Viral Capsid Antigen, IgM; Epstein-Barr Virus Antibody to Viral Capsid Antigen, IgG; Epstein-Barr Virus Antibody to Nuclear Antigen, IgG; Epstein-Barr Virus Antibody to Early D Antigen, IgG; Heterophile Antibodies (see Monos

Related Tests:
Monospot; Full Blood Count; White Blood Cell Count

Why:
To help diagnose glandular fever (also known as Infectious Mononucleosis); to help evaluate susceptibility to EBV infection; to distinguish between an EBV infection and another illness with similar symptoms

When:
When you have symptoms of glandular fever but a negative Monospot test; when a pregnant woman has flu-like symptoms; sometimes when an asymptomatic person has been exposed to EBV

Test General info:
Epstein-Barr virus (EBV) antibodies are a group of tests that are requested to help diagnose a current, recent, or past EBV infection. EBV is a member of the herpes virus family. Passed through the saliva, the virus causes an infection that is very common


Related Tests:
FBC, Urea, Creatinine, Liver Function Tests, Therapeutic Drug Monitoring

Why:
To detect and evaluate toxic concentrations of methotrexate

When:
At specific timed intervals after a high dose of methotrexate to monitor blood concentrations and guide treatment and whenever symptoms suggest methotrexate toxicity

Test Prep:
No test preparation is needed, but timing of the sample for testing is important and the doctor may specify collection at a certain number of hours after a methotrexate dose has been given.No test preparation is needed, but timing of the sample for testin

Test General info:
This test measures the amount of methotrexate in the blood. Methotrexate is a drug that has been in use since the 1960s. It is primarily used to treat childhood acute lymphocytic leukaemia, lymphoma, cancers of the lung, head, neck, and breast, and is als

Related Diseases:
Conditions: Leukaemia, Lymphoma, Breast Cancer, Rheumatoid Arthritis, Liver Disease, Lung Diseases, Kidney Disease


Related Tests:
Sodium; Potassium; Chloride; Bicarbonate; Urea; Creatinine; anion gap

Why:
To detect a problem with the body`s electrolyte balance.

When:
As part of routine blood testing, or when your doctor suspects that you have an imbalance of one of the electrolytes (usually sodium or potassium), or if your doctor suspects an acid-base imbalance. Electrolytes may also be checked if you are prescribed certain drugs, particularly diuretics or ACE inhibitors.

Test General info:
Electrolytes are minerals that are found in body tissues and blood in the form of dissolved salts. As electrically charged particles, electrolytes help move nutrients into and wastes out of the body`s cells, maintain a healthy water balance, and help stab

Related Diseases:
Conditions: Acidosis and Alkalosis, Kidney Diseases, Hypertension, Congestive Heart Failure


Why:
To determine phenytoin concentration in the blood, to maintain an appropriate level, and to detect phenytoin toxicity

When:
At regular intervals to monitor, as needed to detect low or toxic concentrations

Test General info:
This test measures the amount of phenytoin in the blood. Phenytoin is a drug that is used to treat some seizure disorders (also called epilepsy). Seizure disorders affect the brain’s ability to transmit electrical impulses and to regulate nerve activity.


Test Name:
Epilim, Depakote, sodium valproate, semisodium valproate

Other Names:
Epilim, Depakote, sodium valproate, semisodium valproate

Why:
To measure the amount of valproic acid in the blood and to maintain an effective level

When:
To detect low or excessive (potentially toxic) levels

Test General info:
This test measures the amount of valproic acid in the blood. Valproic acid is a drug that is used mainly to treat certain fitting disorders (also called seizures or epilepsy), but is also prescribed to treat bipolar disease (manic depression) and to preve

Related Diseases:
Tests: Therapeutic Drug Monitoring
Conditions: Epilepsy


Related Tests:
Red blood cell count, haemoglobin, haematocrit, FBC, reticulocyte count

Why:
Either to help tell the difference between polycythaemia vera and secondary polycythaemia or to help tell the difference between different types of anaemia. It also shows whether the amount of erythropoietin being produced is appropriate for the level of

When:
If a patient has an elevated red blood cell count or an anaemia that the doctor suspects may be caused by decreased red blood cell production

Test General info:
This test measures the amount of erythropoietin in the blood. Erythropoietin is a hormone produced mainly by the kidneys. It is produced and released into the bloodstream if the blood oxygen levels are low (hypoxaemia). Erythropoietin is carried to the bo

Related Diseases:
Conditions: Anaemia, kidney diseases, bone marrow disorders


Test Name:
Epstein-Barr Virus Antibody to Early D Antigen, IgG


Test Name:
Epstein-Barr Virus Antibody to Nuclear Antigen, IgG


Test Name:
Epstein-Barr Virus Antibody to Viral Capsid Antigen, IgG


Test Name:
Epstein-Barr Virus Antibody to Viral Capsid Antigen, IgM


Other Names:
Parvovirus; Fifth Disease test; Parvo B19; Erythema infectiosum

Why:
To determine if you have, or recently had, a parvovirus B19 infection and if you are at an increased risk of complications from this viral infection

When:
When a pregnant woman has been exposed to someone with parvovirus B19; when a person, especially an immune-compromised person, has persistent or severe anaemia

Sample Type:
A blood sample is taken from a vein in your arm to test for the presence of parvovirus B19 antibody. To detect the virus itself a blood or rarely a bone marrow sample is required.

Test General info:
Parvovirus B19 is a virus that causes a common childhood illness, also called ``fifth disease`` or ``erythema infectiosum.`` It is also known as “Slapped Cheek Disease” because of the typical rash that appears in some children. The virus is found in respi

Related Diseases:
Conditions: Pregnancy, Anaemia, Sickle Cell Anaemia, Thalassaemia


Related Tests:
C-reactive protein (CRP); fibrinogen; immunoglobulins

Why:
To detect and monitor the activity of inflammation as an aid in the diagnosis of the underlying cause

When:
When your doctor thinks that you might have a condition that causes inflammation and to help diagnose and follow the course of this, especially temporal arteritis or polymyalgia rheumatica

Test General info:
ESR is an indirect measure of the degree of inflammation present in the body. It actually measures the rate of fall (sedimentation) of erythrocytes (red blood cells) in a tall, thin tube of blood. Results are reported as how many millimetres of clear plas

Related Diseases:
Conditions: Autoimmune Disorders, Rheumatoid arthritis (RA), Osteoarthritis, Coeliac Disease, Lupus, CFS, JRA


Other Names:
Trace Minerals; Micronutrients; Essential Minerals

Related Tests:
Chromium; Copper; Caeruloplasmin; Fluoride; Iodine; Iron tests; Manganese; Molybdenum; Selenium; Zinc; Vitamin B12 and Folate; Vitamin D

Why:
To detect and monitor a mineral deficiency or excess; sometimes to evaluate your nutritional status

When:
When you have symptoms or signs of a specific mineral deficiency or excess; as indicated when you have a condition that affects mineral absorption, use, or storage

Sample Type:
A blood sample drawn from a vein in your arm; sometimes a random or 24-hour urine sample; rarely, a tissue sample, or another body fluid sample

Test Prep:
Please check with your doctor to find out if you are required to fast before your test is performed.
The Test

Test General info:
Trace elements are a group of tests that measure specific minerals, primarily in the blood but sometimes in the urine or another bodily tissue or fluid. These minerals are substances that the body needs in tiny amounts on a regular basis for normal functi

Related Diseases:
Conditions: Anaemia, Malnutrition, Wilson Disease, Alcoholism, Cystic Fibrosis, Haemochromatosis


When:
When you have unexplained or prolonged bleeding, an abnormal Prothrombin Time (PT) or activated Partial Thromboplastin Time (aPTT) test, or have a relative with a hereditary fibrinogen deficiency or abnormality. To evaluate whether certain abnormalities in a Full Blood Count are due to inflammation or are self-generated. When your doctor wants additional information to help evaluate your risk of developing heart disease

Sample Type:
A blood sample taken from a vein in your arm, or sometimes, via a finger prick (mainly performed in children)

Test General info:
Fibrinogen is a coagulation factor, a protein that is essential for blood clot formation. It is produced by the liver and released into the circulation as needed along with over 20 other clotting factors. Normally, when a body tissue or blood vessel wall

Related Diseases:
Conditions: Excessive Clotting Disorders, Bleeding Disorders, Liver Disease, Cardiovascular Disease, DIC


Other Names:
Factor V Leiden mutation: Activated protein C (APC) resistance; Factor V R506Q; Prothrombin 20210 mutation: PT G20210A; factor II 20210

Formal Name:
Factor V Leiden mutation; Prothrombin 20210 mutation

Related Tests:
Antithrombin; Protein C and Protein S; Homocysteine; Methylenetetrahydrofolate Reductase (MTHFR)

Why:
To determine whether you have an inherited gene mutation that increases your risk of developing a venous thromboembolism

When:
When you have had an unexplained thrombotic episode, especially when you are less than 50 years old and have no other risk factors

Test General info:
Factor V and prothrombin are coagulation factors, a group of proteins produced by the liver that is activated in a step-by-step process called the coagulation cascade when a blood vessel is injured. The result of the coagulation cascade is a blood clot th

Related Diseases:
Tests: Coagulation Factors
Conditions: Hypercoagulable Disorders


Test Name:
Factor V Leiden Mutation andPT 20210 Mutation


Test Name:
Factor V Leiden mutation: Activated protein C resistance


Why:
To screen for bleeding from the gut/intestine, which may be an indicator of bowel cancer

When:
The test is used to screen for bowel cancer especially as part of the National Bowel Cancer Screening Programme. It may also sometimes be used when a patient has a family history of cancer of the intestine and some other organs, when symptoms are suspicious of gut cancer or to help diagnose long-term unexplained anaemia if imaging tests, such as colonoscopy, are unavailable.

Test Prep:
For guaiac-based FOBT (gFOBT) special dental, dietary and drug restrictions may be recommended. These tests detect any blood that enters the digestive tract. Therefore, steps that are taken to avoid introducing blood into the digestive tract will increase

Test General info:
The faecal occult blood test (FOB) or faecal immunological test (FIT) checks for blood in your faeces. Normally, there will not be enough blood lost through the gastrointestinal tract (stomach and intestines) to turn a FOB positive or for you to notice it

Related Diseases:
Conditions: Bowel cancer
Screening: Screening Tests for Adults (50 and up)
In the News: Five-minute screen at sixty can cut bowel cancer deaths


Test Name:
Faecal Occult Blood Test and Faecal Immunochemical Test


Related Tests:
Haemoglobin, Haematocrit, Red blood cell (RBC) count, White blood cell (WBC) count, White blood cell differential count, Platelet count

Why:
To determine general health status and to screen for a variety of disorders, such as anaemia and infection, inflammation nutritional status and exposure to toxic substances

When:
As part of a routine medical examination or as determined by your doctor

Sample Type:
A blood sample taken from a vein in the arm or a finger-prick or heel-prick (newborns)

Test General info:
The full blood count (FBC) is one of the most commonly ordered tests and provides important information about the kinds and numbers of cells in the blood: red blood cells, white blood cells and platelets. Abnormalities in any of these types of cells can i

Related Diseases:
Conditions: Anaemia, Thalassaemia, Vitamin B12 and Folate Deficiency, Sickle Cell Anaemia, Bone Marrow Disorders


Why:
To find out whether the amount of iron in your blood is normal.

When:
Serum iron blood tests are not performed routinely. Most often, serum iron levels are tested if your doctor thinks that you might have too much iron in your blood. A high iron level can be due to a genetic condition, extensive blood transfusions, or rarely due to ingestion of an overdose of iron (usually in children).
Previously, serum iron was also commonly requested when iron deficiency was suspected. However, it is now recommended that the amount of stored iron (in the form of ferritin) rather than serum iron is measured to aid diagnosis of iron deficiency anaemia. Ferritin analysis gives a measure of body iron stores and is a better indicator of iron deficiency than measuring the iron in blood. However, serum iron blood tests can help to identify when anaemia is due to a long-term (chronic) illness.

Test Prep:
Samples for iron should be taken in the morning, before you have had any food to eat. You should not take any iron tablets for 24 hours before the test. Iron is absorbed rapidly from food or tablets, and can make your blood iron levels falsely high.
The

Test General info:
The iron test measures the amount of iron that is circulating in the liquid part of blood bound to transferrin (a transport protein). Iron is an essential trace element in your blood. It is necessary for forming healthy red blood cells. Approximately 70%

Related Diseases:
Tests: Iron Tests
Conditions: Anaemia, haemochromatosis, pregnancy


Related Tests:
Serum Iron, Ferritin; TIBC & UIBC, Transferrin; Zinc protoporphyrin; FBC; Haemoglobin; Haematocrit

Why:
To evaluate your body`s current store of iron

When:
When your doctor suspects that you may have too little or too much iron in your system

Test Prep:
Your doctor may request that you fast for 12 hours prior to some iron blood tests. In this case, only water is permitted.
The Test

Test General info:
Iron is an essential nutrient. It is needed in small quantities to help form normal red blood cells (RBCs). Iron is a critical part of haemoglobin, the protein in red blood cells that binds oxygen in the lungs and releases it as blood travels to other par

Related Diseases:
Conditions: Iron Deficiency Anaemia, Haemochromatosis


Other Names:
ZPP; ZP; Free Erythrocyte Protoporphyrin; FEP

Related Tests:
Serum iron; TIBC; Ferritin; Lead; FBC; Haemoglobin; Haematocrit; Porphyrin tests; Heavy metals

Why:
To screen for and monitor chronic exposure to lead; as an aid in the diagnosis of iron deficiency in children

When:
When you have been chronically exposed to lead, or when your doctor suspects lead poisoning

Test General info:
The test measures the concentration of zinc protoporphyrin (ZPP) in the blood.  ZPP is present in blood in trace amounts and is formed during the production of haem.  Concentrations of ZPP are increased in patients with lead poisoning and iron deficiency.


When:
When your doctor suspects that  you have either too little or too much iron or too much iron in your system

Test Prep:
You may be instructed to fast for 12 hours before the test; in this case, only water is permitted.
The Test

Test General info:
Within cells, iron is stored as protein complexes called ferritin and haemosiderin. Ferritin is the main storage complex and is present mostly in the liver, but also in the bone marrow, spleen, and muscles. Small amounts of ferritin also circulate in the

Related Diseases:
Tests: Iron Tests Overview
Conditions: Anaemia, haemochromatosis


Why:
To learn about the levels of iron stored in your body


Formal Name:
First Trimester Screen [Pregnancy-associated plasma protein-A (PAPP-A), free beta human chorionic gonadotropin (hCG) as either free beta subunit or total hCG, and nuchal translucency (NT) ultrasound]

Related Tests:
Triple Screen or Quad Screen; hCG; Amniotic Fluid Analysis; Chromosome Analysis

Why:
To assess the risk of a foetus having a chromosomal abnormality, such as Down’s syndrome (trisomy 21).

When:
Usually between 11 and 14 weeks of pregnancy.

Sample Type:
A blood sample taken from a vein in your arm. Measurement of nuchal translucency (NT) requires a special ultrasound examination to be performed.

Test Prep:
You may be requested to have a full bladder when having the nuchal translucency ultrasound scan performed. Having a full bladder when you attend for your scan usually makes it easier to see the baby clearly and measure the nuchal translucency.
The Test

Test General info:
The first trimester screen is a combination of two blood tests and a special ultrasound scan that are used to assess a pregnant woman`s risk of carrying a baby with Down’s syndrome (trisomy 21). Performing and evaluating them together, along with the woma


Test Name:
First Trimester Screen Down’s Syndrome Screen


Related Tests:
Ciclosporin; Therapeutic drug monitoring; Urea; Creatinine; Electrolytes; Potassium; Magnesium; Glucose

Why:
To measure the concentration of tacrolimus in the blood in order to establish the correct dose, maintain therapeutic levels and detect toxic levels

When:
As soon as tacrolimus therapy begins, frequently at first then at regular intervals to monitor concentrations over time

Test Prep:
Have the blood sample collected 12 hours after the last dose and/or immediately prior to the next dose or as directed by your doctor
The Test

Test General info:
This test measures the amount of tacrolimus in the blood. Tacrolimus is an immunosuppressive drug that is given orally or intravenously to patients who have had a kidney, liver, heart, or other organ transplant. It is a powerful drug that helps to prevent

Related Diseases:
Tests: Ciclosporin; Therapeutic drug monitoring; Urea; Creatinine; Electrolytes; Potassium; Magnesium; Glucose
Features: Pharmacogenomics


Why:
To identify the type or strain of flu virus that you have

When:
If your doctor wants to determine whether your flu-like symptoms are due to a particular type or strain of the influenza virus, or due to other causes

Sample Type:
Usually a nose or throat swab
The Test Sample

Test General info:
Influenza (the flu) is a viral infection that tends to be seasonal, beginning in late November and disappearing in early spring. It is a common respiratory (affecting the lungs) illness that causes headaches, fever, chills, muscle pains, exhaustion, a stu


Test Name:
Fluorescent antinuclear antibody , ANA ELISA


Other Names:
Vitamin B12 or Cobalamin; Folic Acid; RBC folate

Related Tests:
FBC; Methylmalonic acid (MMA); Homocysteine

Why:
To help diagnose the cause of anaemia or neuropathy (nerve damage), to evaluate nutritional status in some patients, to monitor effectiveness of treatment for B12 or folate deficiency

When:
When you have large red blood cells, when you have symptoms of anaemia and/or of neuropathy. When you are being treated for B12 or folate deficiency

Test General info:
These tests measure the concentration of folate and vitamin B12 in the serum (liquid portion of the blood). The amount of folate inside the red blood cell (RBC) may also be measured - it will normally be at a higher concentration inside the cell than in t

Related Diseases:
Tests: FBC, Coeliac disease tests, Homocysteine, Methylmalonic acid (MMA)
Conditions: Anaemia, Alcoholism, Autoimmune disorders, Coeliac disease, Cystic fibrosis, HIV, Neuropathy,Pregnancy


Why:
To evaluate the function of your pituitary gland, which regulates the hormones that control your reproductive system

When:
If you are having difficulty getting pregnant or are having irregular menstrual periods, if your doctor thinks that you have symptoms of a pituitary, ovarian or testicular or hypothalamic disorder or when your doctor suspects that a child has delayed or earlier than expected sexual maturation.

Test Prep:
No, but in a women, the sample should be taken in the first 4 days of her cycle.
The Test

Test General info:
Follicle-stimulating hormone (FSH) is made by the pituitary gland in the brain. Control of FSH production is a complex system involving hormones produced by the gonads (ovaries or testes), the pituitary gland, and the hypothalamus, such as gonadotrophin-r

Related Diseases:
Conditions: Infertility, menopause
Tests: LH, oestradiol, progesterone, testosterone


Why:
To diagnose hypothyroidism or hyperthyroidism in adults and to monitor response to treatment

When:
When you have symptoms of an underactive (hypothyroidism) or overactive (hyperthyroidism) thyroid gland

Test General info:
This test measures free thyroxine, or FT4, in your blood.  Thyroxine is one of two major hormones produced by the thyroid gland (the other is called triiodothyronine (T3)). Within the blood, most thyroid hormones are attached to a protein, but it is the h


When:
If you get an abnormal TSH , T4 or FT4 result

Test Prep:
None needed; however, certain medications can interfere with the FT3 test, so tell your doctor about any drugs that you are taking
The Test

Test General info:
The test measures the amount of free triiodothyronine, or FT3, in your blood.
T3 is one of two major hormones produced by the thyroid gland (the other hormone is called thyroxine, or T4). The thyroid gland is found in the neck, in front of the windpipe.


When:
When you are diabetic and your doctor wants to evaluate your average blood glucose level over the last 2-3 weeks

Test General info:
The fructosamine test is a measurement of glycated protein, mainly albumin. When glucose levels in the blood are elevated over a period of time, glucose molecules permanently combine with proteins in the blood in a process called glycation. Affected prote


When:
If you have symptoms of a syphilis infection, if you have another STD, or are pregnant

Sample Type:
Usually a scraping from a chancre (ulcer or sore) in the affected area, a blood sample from a vein in your arm, or a spinal tap (lumbar puncture), depending on the test being used
The Test Sample

Test General info:
The test is looking for evidence of Treponema pallidum, the bacterium that causes syphilis. Syphilis is a sexually transmitted disease. It is easily treated but can cause severe health problems if left untreated.


Formal Name:
Potassium hydroxide preparation, Fungal culture, Fungal antigen and antibody tests, and Calcofluor white stain

Related Tests:
AFB smear and culture, CSF analysis, Susceptibility testing, Gram stain, Bacterial wound culture

Why:
To detect a fungal infection, to determine which specific fungus or fungi are present, and sometimes to isolate and grow the fungi for subsequent susceptibility testing

When:
When the doctor suspects that you have a skin, lung, or systemic fungal infection; sometimes after treatment to monitor its effectiveness

Sample Type:
The sample collected depends upon the suspected location(s) of the infection. It typically includes: scrapings of the skin, nail and hair samples, fluids, blood, and/or a tissue biopsy.

Test General info:
Fungi are microorganisms that exist in nature as either yeast or moulds. There are more than 50,000 species of fungi in the environment, but less than 200 species are associated with human disease. Of these, only about 20 to 25 species are common causes o

Related Diseases:
Conditions: Wound and skin infections, Tuberculosis, Nontuberculous mycobacteria, Lung diseases, Traveler’s diseases


Related Tests:
FBC; Blood film; Reticulocyte count; Bilirubin; RBC count; Haemoglobin; Autohaemolysis test; Heinz body stain

Why:
To see whether you have an inherited deficiency of Glucose-6-Phosphate Dehydrogenase (G6PD), necessary to keep red blood cells healthy

When:
If a child has long term jaundice as a newborn and no other cause can be identified; when you have had one or more bouts of haemolysis (break-up of red blood cells, which may cause jaundice, dark urine or anaemia), particularly if the haemolysis follows ``oxidative`` stress caused by some medicines, foods, or infections

Test General info:
This test measures the amount of G6PD in the red blood cells (RBCs). G6PD is an  enzyme that protects red blood cells from the effects of oxidation. If there is insufficient G6PD, the RBCs become more vulnerable to oxidative damage. If these RBCs are expo

Related Diseases:
Conditions: Anaemia
Screening:  Screening Tests for Newborns


Related Tests:
AST; ALT; ALP; bilirubin; liver function tests (LFTs)

Why:
To screen for liver disease or alcohol abuse; and to help your doctor tell whether a raised concentration of alkaline phosphatase (ALP) in the bloodstream is due to liver or bone disease

When:
If your doctor thinks that you have symptoms of a liver disorder/disease

Test General info:
Gamma-glutamyl transferase (GGT) is an enzyme found mainly in the liver. When the liver is injured or the flow of bile is obstructed, the concentration of GGT within the bloodstream rises. It is therefore a useful marker for detecting bile duct problems.


When:
When you have peptic ulcers and/or diarrhoea and abdominal pain that your doctor suspects is caused by excess gastrin; periodically to monitor for a gastrinoma recurrence

Test Prep:
You should fast for 12 hours and avoid alcohol for 24 hours prior to the test. Your doctor may also ask you to stop taking certain stomach medicines for several days before the test.
The Test

Test General info:
This test measures the amount of gastrin in the blood. Gastrin is a hormone that regulates the production of acid in the stomach. It is produced by special cells called G-cells in the stomach during the digestive process. When food is eaten, the stomach b


Why:
To screen for infection with HPV, some types of which are associated with cervical cancer

When:
If you are sexually active, have symptoms of HPV infection (genital warts), or have an irregular cervical smear test

Sample Type:
A sampling of cells from the cervical area
The Test Sample

Test General info:
The test is looking for evidence of infection by human papilloma virus (HPV), a virus that can cause skin warts and genital warts (also called condylomata) and that has been linked to cervical, penile, and other forms of genital cancer.

Related Diseases:
Conditions: Sexually transmitted diseases, Cervical cancer


Why:
To determine if you have had a recent or past infection with the rubella virus, or to check that you are protected from the rubella virus

When:
If you plan to get pregnant or have symptoms of rubella infection

Sample Type:
A blood sample taken from a vein in the arm (this may need to be repeated after 7 days), oral fluid, a throat swab, or other more invasive samples such as amniotic fluid depending on symptoms.

Test General info:
Rubella is a viral infection that causes a fine red rash and flu-like symptoms, such as a high temperature, headache and a general feeling of being unwell. The raised red rash appears first on the face and neck and travels to the body and limbs. Teenagers


When:
When you have symptoms of mercury poisoning, to evaluate a known exposure to mercury, or to monitor occupational exposure to mercury

Sample Type:
A blood sample taken from a vein in your arm and/or a urine collection

Test Prep:
No test preparation is needed.  
The Test

Test General info:
Mercury is an element that exists in three forms:
Metallic or elemental mercury. This form can be found in dental fillings, some thermometers and batteries. 
Inorganic mercury where it has combined with other elements such as oxygen or sulphur to form a


Related Tests:
Haemoglobin Electrophoresis; Isoelectric Focusing; Haemoglobin S Solubility; Haemoglobin Fractionation by HPLC; Haemoglobinopathy Evaluation, Full Blood Count, Blood Film, Iron Tests

Why:
To screen for the presence of sickle cell trait or to confirm the presence of sickle cell disease

When:
If you are of Afro-Carribean descent to determine if you carry one or both genes for sickle cell disease and for antenatal screening. There are other ethnic minorities in whom the sickle gene is found and should be tested if index of clinical suspicion is high.

Sample Type:
A blood sample taken from a vein in the arm. In children, a blood sample from a finger-prick or heel-prick

Test Prep:
No test preparation is needed; however, testing for diagnosis should not be performed after a recent blood transfusion.
The Test

Test General info:
Blood is tested for the presence of Haemoglobin S (HbS), which is a genetic variant of the protein haemoglobin. Haemoglobin is found inside red blood cells (RBCs) and is responsible for carrying oxygen from the lungs to all of the tissues and organs of th


Other Names:
Herpes Culture; Herpes Simplex Viral Culture; HSV DNA; HSV by PCR; HSV-1 or HSV-2 IgM or IgG; HSV-1; HSV-2; HHV1; HHV2

Why:
To screen for or diagnose infection with herpes simplex virus

When:
If you have symptoms of an infection with herpes simplex virus

Sample Type:
A swab or scraping from a blister or sore in the infected area

Test General info:
The test is looking for evidence of infection by herpes simplex virus, a common sexually transmitted disease that causes small blisters (vesicles) on the mouth or genitals. The blisters seen around the oral cavity and in the mouth are commonly called “col


Related Tests:
Cholesterol; LDL; Triglycerides; Lipid profile

Why:
To find out the risk of developing heart disease

When:
As part of a health check with a cholesterol test or lipid profile particularly if you:
have a family history of cholesterol disorders 
have a family history of heart attacks, especially at a young age 
are overweight 
have diabetes 
have thick yellow patches (xanthelasmata) around your eyes or elsewhere on your skin (xanthomata) 
have high blood pressure 
have had acute inflammation of the pancreas (acute pancreatitis) 
are a smoker

Sample Type:
A blood sample taken from a vein in the arm or from a finger-prick
The Test Sample

Test General info:
HDL is one of the classes of lipoproteins that carry cholesterol in the blood. HDL is thought to be beneficial because it removes excess cholesterol from tissues and carries it to the liver for disposal. Hence HDL cholesterol is often called “good” choles


Test Name:
High-sensitivity cardiac-specific Troponins I and T


Why:
If you have been diagnosed with HIV and are receiving anti-viral therapy that is not working effectively

When:
If your HIV viral load values rise steadily even though you are receiving anti-viral therapy

Test General info:
In genotypic resistance testing, the genetic code of the particular strain of HIV a patient has is checked to see if there any genetic mutations that are known to cause drug resistance. HIV is said to be resistant to an antiviral medication if it keeps mu


Other Names:
GH; Human Growth Hormone (HGH); Somatotropin

Related Tests:
IGF-1 (Insulin-like growth factor-1; also called Somatomedin C); GHRH (Growth Hormone Releasing Hormone); Glucose Tolerance Test; Cortisol; ACTH; TSH; Glucose; Prolactin

Why:
To identify diseases and conditions caused by either a deficiency or overproduction of growth hormone (GH), to evaluate pituitary function, and to monitor the effectiveness of GH treatment

When:
As part of an evaluation of pituitary function. Slow growth in stature, delayed development (in children), decreased bone density and/or muscle strength, and increased lipids (in adults) all could be related to insufficient GH production. Symptoms suggestive of gigantism in children or acromegaly in adults may be a result of excess GH production

Sample Type:
Usually several blood samples are taken at timed intervals from veins in your arm. Sometimes a single sample of blood is required following a fast or after a period of strenuous exercise

Test Prep:
In healthy adults, GH levels remain stable, but rise sharply 3-4 hours after a meal and within 60 minutes after the onset of sleep. One sample should therefore be taken fasting.
The Test

Test General info:
Growth hormone (GH) is essential for a child’s normal growth and development and promotes proper long bone growth from birth through puberty. Children with insufficient GH production grow more slowly and are smaller in size for their age; one of the first

Related Diseases:
Tests: ACTH, IGF-1, Prolactin, T4, TSH, Cortisol, FSH, LH, Testosterone, Glucose
Conditions: Pituitary Disorders, Thyroid Diseases


Other Names:
Glycated Serum Protein (GSP); Glycated Albumin

Why:
To help monitor your diabetes over time, especially if it is not possible to monitor using the HbA1C test; to help determine the effectiveness of changes to your diabetic treatment plan


Why:
To monitor a person’s diabetes and to help treatment decisions. It can also be used to diagnose type 2 diabetes.

When:
When first diagnosed with diabetes and then at least twice a year

Test General info:
Some of the glucose in your blood binds to haemoglobin (the protein that carries oxygen in your red blood cells). This combination of glucose and haemoglobin is called haemoglobin A1c (HbA1c). The amount of HbA1c formed is directly related to the average


Why:
To screen for Neisseria gonorrhoeae, which causes the sexually transmitted disease gonorrhoea

When:
If you have symptoms of gonorrhoea or are pregnant

Sample Type:
A swab of secretion or discharge from the infected area
The Test Sample

Test General info:
The test is looking for evidence of the bacterium Neisseria gonorrhoeae, which causes the sexually transmitted disease gonorrhoea. Gonorrhoea is easily treated but can cause severe reproductive and health problems if left untreated.


Related Tests:
Susceptibility Testing, Bacterial Wound Culture, Blood Culture, CSF Analysis, Urine Culture, AFB Smear and Culture, Gonorrhoea, Stool Culture, Fungal Tests, Sputum Culture, Synovial Fluid Analysis, Pleural Fluid Analysis, Pericardial Fluid Analysis, Perit

Why:
To identify the cause of a bacterial infection so appropriate treatment can be given

When:
If your doctor suspects that you have a bacterial infection

Sample Type:
A swab of cells or fluid taken from the site of infection
The Test Sample

Test General info:
A Gram stain is used to determine if bacteria are present in an area of the body that is normally sterile, such as spinal fluid. A sample from the infected area is smeared on a glass slide and allowed to dry. A series of stains are applied and then the st

Related Diseases:
Conditions: Wound and Skin Infections, Staph Wound Infections, Meningitis and Encephalitis, Fungal Infections, PID, Septic Arthritis, Urinary Tract Infection, Pneumonia, Sepsis


