April 18, 2012
Fact Sheet 121 for information on the Complete Blood Count and Fact Sheet 123 for information on blood glucose (sugar) and cholesterol tests.
Laboratories have different "reference ranges" or normal values for the results of each test. Most lab reports show the normal range and highlight any test results outside the normal range. For more information on normal laboratory test results, see Fact Sheet 120, Normal Laboratory Values.
The mineral calcium is a major component of bones and teeth. Calcium is also needed for nerves and muscles to work properly, and in chemical reactions in the cells. The body controls the amount of calcium in the blood. However, the amount of protein in the blood can affect calcium test results (see albumin). The most common cause of low calcium test results for people with HIV is low protein levels due to malnutrition or wasting. Abnormal calcium levels can indicate digestive problems.
Phosphorus, like calcium, is a major component of bones. Low levels of phosphorus for a long period of time can cause damage to bones, nerves and muscles. High phosphate levels are most often due to kidney failure.
Glucose is sugar, which is broken down in the cells to provide energy. See Fact Sheet 123 for more information on blood glucose tests.
Blood Urea Nitrogen (BUN) is nitrogen in the blood. This is a waste product that is normally removed by the kidneys in the urine. High BUN levels can be due to a high-protein diet, dehydration, or kidney or heart failure.
Creatinine is a waste product of protein digestion and a measure of kidney function. High levels are usually due to kidney problems. Doctors use the creatinine level as the most direct sign of how well the kidneys are removing waste products from the body.
Different patterns of these enzymes -- when some are elevated and others are normal -- can help your doctor identify specific health problems. Laboratory tests include:
Albumin is the major protein in the blood. It maintains water balance in the cells, carries nutrients to the cells and removes waste products. Low albumin is generally a sign of nutrition problems.
Because albumin carries so many substances in the blood, low albumin levels can cause incorrect low results for other laboratory tests, especially calcium or testosterone.
Globulin (also called immunoglobulin) measures the protein in antibodies produced by the immune system. HIV infection causes an abnormally high level of globulin. Levels are usually reported for five types of globulin: IgG, IgA, IgD, IgE and IgM.
Sedimentation Rate (Erythrocyte Sedimentation Rate) or Sed Rate measures how quickly red blood cells settle in a tube of blood. A high sed rate indicates some type of inflammation. However, the sed rate does not indicate whether the inflammation is long-term, like arthritis, or is due to the body fighting an infection.
The C-Reactive Protein test or CRP is another general test of inflammation. It rises and falls faster than the Sed Rate. High levels of CRP may be a sign of increased risk of heart attack.
www.labtestsonline.org/ or go to MEDLINEplus at www.medlineplus.gov/ and search for a specific test.
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