A-Z Listing of Biomedical Lab Tests

The liver makes more ALP than the other organs or the bones. Some conditions cause large amounts of ALP in the blood. These conditions include rapid bone growth (during puberty), bone disease (osteomalacia or Paget's disease), or a disease that affects how much calcium is in the blood (hyperparathyroidism), vitamin D deficiency, or damaged liver cells.

Alpha-fetoprotein, AFP is a major plasma protein produced by the yolk sac and the liver during fetal development. High alpha-fetoprotein values can mean cancer of the liver, testicles, or ovaries is present, liver disease, such as cirrhosis or hepatitis, is present or alcohol abuse is present.

ALT was formerly called serum glutamic pyruvic transaminase (SGPT). ALT is measured to see if the liver is damaged or diseased. Low levels of ALT are normally found in the blood. But when the liver is damaged or diseased, it releases ALT into the bloodstream, which makes ALT levels go up. Most increases in ALT levels are caused by liver damage.

AST formerly was called serum glutamic oxaloacetic transaminase (SGOT). When body tissue or an organ such as the heart or liver is diseased or damaged, additional AST is released into the bloodstream. The amount of AST in the blood is directly related to the extent of the tissue damage. After severe damage, AST levels rise in 6 to 10 hours and remain high for about 4 days.

Blood group is identified by antigens and antibodies present in the blood.

Blood groups are defined by the ABO system.

Red blood cells sometimes have another antigen, a protein known as the RhD antigen. If this is present, your blood group is RhD positive. If it is absent, your blood group is RhD negative.

Urea is made when protein is broken down in your body. Urea is made in the liver and passed out of your body in the urine. A BUN test is done to see how well your kidneys are working. If your kidneys are not able to remove urea from the blood normally, your BUN level rises. Heart failure, dehydration, or a diet high in protein can also make your BUN level higher. Liver disease or damage can lower your BUN level. A low BUN level can occur normally in the second or third trimester of pregnancy.

CA 125 is the standard tumor marker used to follow women during or after treatment for epithelial ovarian cancer (the most common type of ovarian cancer). Normal blood levels are usually less than 35 U/mL (units/milliliter). More than 90% of women with advanced ovarian cancer have high levels of CA 125. If the CA-125 level is increased at the time of diagnosis, changes in the CA-125 level can be used during treatment to get an idea of how well it’s working. Levels are also elevated in about half of women whose cancer has not spread outside of the ovary. Because of this, CA 125 has been studied as a screening test. But the trouble with using it as a screening test is that it would still miss many early cancers, and problems other than ovarian cancer can cause an elevated CA-125 level. For example, it’s often higher in women with uterine fibroids or endometriosis. It may also be higher in men and women with lung, pancreatic, breast, liver, and colon cancer, and in people who have had cancer in the past. Because ovarian cancer is a rather rare disease, an increased CA-125 level is more likely to be caused by something other than ovarian cancer.

CA 15-3 is mainly used to watch patients with breast cancer. Elevated blood levels are found in less than 10% of patients with early disease and in about 70% of patients with advanced disease. Levels usually drop if treatment is working, but they may go up in the first few weeks after treatment is started. (This rise is caused when dying cancer cells spill their contents into the bloodstream.) Level as high as 100 U/mL can be seen in women who do not have cancer. Levels of this marker can also be higher in other cancers, like lung, colon, pancreas, and ovarian, and in some non-cancerous conditions, like benign breast conditions, ovarian disease, endometriosis, and hepatitis.

The CA 19-9 test was first developed to detect colorectal cancer, but it’s most often used in people with pancreatic cancer. In very early disease the level is often normal, so it’s not good as a screening test. Still, it’s the best tumor marker for following patients who have cancer of the pancreas. CA 19-9 can be elevated in other forms of digestive tract cancer, especially cancers of the stomach and bile ducts, and in some non-cancerous conditions such as inflammatory bowel disease, and pancreatitis (inflammation of the pancreas).

The body needs it to build and fix bones and teeth, help nerves work, make muscles squeeze together, help blood clot, and help the heart to work. Almost all of the calcium in the body is stored in bone. The rest is found in the blood. It is important to get the right amount of calcium in your food because the body loses calcium every day. Foods rich in calcium include dairy products (milk, cheese), eggs, fish, green vegetables, and fruit. Most people who have low or high levels of calcium do not have any symptoms.

CEA is not used to diagnose or screen for colorectal cancer, but it’s the preferred tumor marker to help predict outlook in patients with colorectal cancer. It is usually present only at very low levels in the blood of healthy adults. Serum levels can also be elevated in heavy smokers. CEA may be used for lung and breast cancer.

The body uses cholesterol to help build cells and produce hormones. Too much cholesterol in the blood can build up inside arteries, forming what is known as plaque. Large amounts of plaque increase your chances of having a heart attack or stroke.

Creatinine is made at a steady rate and is not affected by diet or by normal physical activities. If your kidneys are damaged and cannot work normally, the amount of creatinine in your urine goes down while its level in your blood goes up. The blood creatinine level shows how well your kidneys are working. A high creatinine level may mean your kidneys are not working properly. The amount of creatinine in the blood depends partly on the amount of muscle tissue you have; men generally have higher creatinine levels than women.

Electrolytes are minerals, such as sodium, chloride and potassium that are found in the body. They keep your body's fluids in balance and help keep your body working normally, including your heart rhythm, muscle contraction, and brain function.

The sedimentation rate (sed rate) blood test measures how quickly red blood cells (erythrocytes) settle in a test tube in one hour. When inflammation is present in the body, certain proteins cause red blood cells to stick together and fall more quickly than normal to the bottom of the tube. These proteins are produced by the liver and the immune system under many abnormal conditions, such as an infection, an autoimmune disease, or cancer. There are many possible causes of a high sedimentation rate. For this reason, a sed rate is done with other tests to confirm a diagnosis. After a diagnosis has been made, a sed rate can be done to help check on the disease or see how well treatment is working.

Gamma-glutamyltransferase is found in many tissues, the most notable one being the liver, and has significance in medicine as a diagnostic marker. An increased level of GGT is seen with alcohol use or diseases of the bile ducts.

A blood glucose test measures the amount of a type of sugar, called glucose, in your blood. Glucose comes from carbohydrate foods. It is the main source of energy used by the body. Insulin is a hormone that helps your body's cells use the glucose. Insulin is produced in the pancreas and released into the blood when the amount of glucose in the blood rises.
Normally, your blood glucose levels increase slightly after you eat. This increase causes your pancreas to release insulin so that your blood glucose levels do not get too high. Blood glucose levels that remain high over time can damage your eyes, kidneys, nerves, and blood vessels.

There are several different types of blood glucose tests.
Fasting blood sugar (FBS) measures blood glucose after you have not eaten for at least 8 hours. It is often the first test done to check for prediabetes and diabetes.
2-hour postprandial blood sugar measures blood glucose exactly 2 hours after you start eating a meal. This is not a test used to diagnose diabetes.

Random blood sugar (RBS) measures blood glucose regardless of when you last ate. Several random measurements may be taken throughout the day. Random testing is useful because glucose levels in healthy people do not vary widely throughout the day. Blood glucose levels that vary widely may mean a problem. This test is also called a casual blood glucose test. Random testing is not used to diagnose diabetes.

Oral glucose tolerance test is used to diagnose prediabetes and diabetes. An oral glucose tolerance test is a series of blood glucose measurements taken after you drink a sweet liquid that contains glucose. This test is commonly used to diagnose diabetes that occurs during pregnancy (gestational diabetes). This test is not commonly used to diagnose diabetes in a person who is not pregnant.
Glycohemoglobin A1c measures how much sugar (glucose) is stuck to red blood cells. This test can be used to diagnose diabetes. It also shows how well your diabetes has been controlled in the last 2 to 3 months and whether your diabetes medicine needs to be changed. The result of your A1c test can be used to estimate your average blood sugar level.

Helicobacter pylori tests are used to detect a Helicobacter pylori (H. pylori) infection in the stomach and upper part of the small intestine (duodenum). H. pylori can cause peptic ulcers. But most people with H. pylori in their digestive systems do not develop ulcers.

Four tests are used to detect H. pylori:
Blood antibody test. A blood test checks to see whether your body has made antibodies to H. pylori bacteria. If you have antibodies to H. pylori in your blood, it means you either are currently infected or have been infected in the past.

Urea breath test. A urea breath test checks to see if you have H. pylori bacteria in your stomach. This test can show if you have an H. pylori infection. It can also be used to see if treatment has worked to get rid of H. pylori.

Stool antigen test. A stool antigen test checks to see if substances that trigger the immune system to fight an H. pylori infection (H. pylori antigens) are present in your feces (stool). Stool antigen testing may be done to help support a diagnosis of H. pylori infection or to determine whether treatment for an H. pylori infection has been successful.

Stomach biopsy. A small sample (biopsy) is taken from the lining of your stomach and small intestine during an endoscopy. Several different tests may be done on the biopsy sample

The hemoglobin molecule fills up the red blood cells. It carries oxygen and gives the blood cell its red color. The hemoglobin test measures the amount of hemoglobin in blood and is a good measure of the blood's ability to carry oxygen throughout the body.

This test measures the amount of space (volume) red blood cells take up in the blood. The value is given as a percentage of red blood cells in a volume of blood.  Hematocrit and hemoglobin values are the two major tests that show if anemia or polycythemia is present.

A person who recovers completely from a hepatitis B infection or had a successful hepatitis B immunization will have Anti-HBs. The level of Anti-HBs will decrease with time. Those who acquire the Anti-HBS through immunization will require a booster dose if the level falls below 100 mIU/ml.

HBs Ag is a part of the capsule of the hepatitis B virus and if positive represents hepatitis B infection. If the liver enzymes are normal, the person is a carrier of hepatitis B. If the enzymes are high for more than a few months, that person is suffering from chronic hepatitis B. Both groups have a higher risk of liver cancer than the normal population.

HBs Ag is a part of the capsule of the hepatitis B virus and if positive represents hepatitis B infection. If the liver enzymes are normal, the person is a carrier of hepatitis B. If the enzymes are high for more than a few months, that person is suffering from chronic hepatitis B. Both groups have a higher risk of liver cancer than the normal population.

LDL molecules are often informally called bad cholesterol because they can transport their content of many fat molecules into artery walls, attract macrophages, and thus drive atherosclerosis. Higher levels of LDL cholesterol increase your risk of heart attacks.

In this test, a drop of blood is spread (smeared) on a slide and stained with a special dye. The slide is looked at under a microscope. The number, size, and shape of red blood cells, white blood cells, and platelets are recorded. Blood cells with different shapes or sizes can help diagnose many blood diseases, such as leukemia, malaria, or sickle cell disease.

The body needs phosphorus to build and repair bones and teeth, help nerves function, and make muscles contract. Most (about 85%) of the phosphorus contained in phosphate is found in bones. The rest of it is stored in tissues throughout the body.Extra phosphate is filtered by the kidneys and passes out of the body in the urine. A high level of phosphate in the blood is usually caused by a kidney problem.

Platelets (thrombocytes) are the smallest type of blood cell. They are important in blood clotting. When bleeding occurs, the platelets swell, clump together, and form a sticky plug that helps stop the bleeding. If there are too few platelets, uncontrolled bleeding may be a problem. If there are too many platelets, there is a chance of a blood clot forming in a blood vessel. Also, platelets may be involved in hardening of the arteries (atherosclerosis).

Prostate-specific antigen (PSA) is a substance produced by the prostate gland. Elevated PSA levels may indicate prostate cancer, a noncancerous condition such as prostatitis, or an enlarged prostate. Most men have PSA levels under four (ng/mL) and this has traditionally been used as the cutoff for concern about the risk of prostate cancer. Men with prostate cancer often have PSA levels higher than four, although cancer is a possibility at any PSA level.

Prostate-specific antigen (PSA) is a substance produced by the prostate gland. Elevated PSA levels may indicate prostate cancer, a noncancerous condition such as prostatitis, or an enlarged prostate. Most men have PSA levels under four (ng/mL) and this has traditionally been used as the cutoff for concern about the risk of prostate cancer. Men with prostate cancer often have PSA levels higher than four, although cancer is a possibility at any PSA level.

Rheumatoid arthritis (RA) is an autoimmune disease that results in a chronic, systemic inflammatory disorder that may affect many tissues and organs, but principally attacks flexible (synovial) joints. It can be a disabling and painful condition, which can lead to substantial loss of functioning and mobility if not adequately treated.

Thyroid hormones are needed for normal development of the brain, especially during the first 3 years of life. Intellectual disability may occur if a baby's thyroid gland does not produce enough thyroid hormone (congenital hypothyroidism). Older children also need thyroid hormones to grow and develop normally, and adults need the hormones to regulate the way the body uses energy (metabolism). Thyroid hormone blood tests include T4, FT4, FT3 and TSH.

Bilirubin is a brownish yellow substance found in bile. It is produced when the liver breaks down old red blood cells. Bilirubin is then removed from the body through the stool (feces) and gives stool its normal brown colour. The bilirubin test is used to check liver function and watch for signs of liver disease, find out if something is blocking the bile ducts, diagnose conditions that cause increased destruction of red blood cells and help make decisions about whether newborn babies with neonatal jaundice need treatment.

A total serum protein test measures the total amount of protein in the blood. It also measures the amounts of two major groups of proteins in the blood: albumin and globulin.

Triglycerides are a type of lipid found in blood. Any protein, carbohydrate or fat not being immediately used from food intake ends up as triglycerides. Triglycerides are stored in fat cells and later being released by the hormones for energy between meals. High calorie intake (e.g.carbohydrates, fructose, alcohol) with little exercise leads to high triglyceride level. High triglycerides level puts an individual more at risk of heart disease, and even more so when blood cholesterol level is also elevated.  

Urine test strips are used to measure certain constituents in urine which are significant of renal, urinary, hepatic and metabolic disorders.
Glucose: The glucose oxidized by glucose oxidase catalyzes the formation of glucuronic acid and peroxide hydrogen. Peroxide hydrogen releases neo-ecotype oxide [O-] which oxidizes potassium iodide, which makes the colour changes.

A microalbumin test checks urine for the presence of a protein called albumin. Albumin is normally found in the blood and filtered by the kidneys. When the kidneys are working properly, albumin is not present in the urine. But when the kidneys are damaged, small amounts of albumin leak into the urine. This condition is called microalbuminuria. Microalbuminuria is most often caused by kidney damage from diabetes. But many other conditions can lead to kidney damage, such as high blood pressure, heart failure, cirrhosis, or systemic lupus erythematosus (SLE). If early kidney damage is not treated, larger amounts of albumin and protein may leak into the urine. This condition is called macroalbuminuria or proteinuria. When the kidneys spill protein, it can mean serious kidney damage is present. This can lead to chronic kidney disease.

The VDRL test checks for an antibody that can be produced in people who have syphilis. This antibody is not produced as a reaction to the syphilis bacteria specifically, so this test is sometimes not accurate. The VDRL test may be done on a sample of blood or spinal fluid. The VDRL test is not very useful for detecting syphilis in very early or advanced stages. The TPHA test is used to confirm a syphilis infection after another method tests positive for the syphilis bacteria. This test detects antibodies to the bacteria that cause syphilis.

White blood cells are made in the bone marrow and protect the body against infection. If an infection develops, white blood cells attack and destroy the bacteria, virus, or other organism causing it. White blood cells are bigger than red blood cells and normally are fewer in number. When a person has a bacterial infection, the number of white cells can increase dramatically
There are five types of white blood cells: lymphocytes, monocytes, neutrophils, basophils, and eosinophils.