Alternative Names prostatic acid phosphatase test, serum acid phosphatase test, PAP test, tartrate-resistant acid phosphatase test, TRAP test
Definition The acid phosphatase test measures the level of acid phosphatase in the blood. Acid phosphatase is an enzyme found in the prostate gland, semen, liver, spleen, blood cells, and bone marrow. If these organs and tissues are not functioning right, they may release acid phosphatase into the bloodstream.
Who is a candidate for the test? The acid phosphatase test was used primarily to diagnose and stage cancer of the prostate and to monitor the effect of the treatment. It may also be used to detect damage to the heart, liver, and other organs. Now a days there are more specific test that are used for prostate cancer detection.
How is the test performed? In order to measure the amount of acid phosphatase in the blood, a blood sample is taken from a vein in the arm. First, the skin over the vein is cleaned with an antiseptic. A tourniquet is wrapped around the upper arm to enlarge the veins. A small needle is gently inserted into a vein, and blood is collected for testing in the laboratory. After the tourniquet is removed a cotton ball is held over the needle site until bleeding stops.
What is involved in preparation for the test? A person should request specific instructions from his or her doctor.
What do the test results mean? A normal level of acid phosphatase in the blood is 0 to 0.8 U/L (units per litre). Abnormal levels of acid phosphatase in the blood may indicate one or more of the following:
prostate cancer that has spread outside the prostate gland, often to bone
decreased flow of blood to the prostate gland
Paget's disease, a disease in which bones thicken and soften
anaemia, a decreased number of circulating red blood cells
infection
prostatitis, or inflammation of the prostate gland
thrombophlebitis, inflammation and small blood clots in a vein, usually in the leg
physical stimulation of the prostate gland, which can be done by prostate examination, colonoscopy, or enemas
multiple myeloma, a malignancy beginning in the plasma cells of the bone marrow
Author: David T. Moran, MD Reviewer: eknowhow Medical Review Panel Editor: Dr John Hearne Last Updated: 19/05/2005 Contributors Potential conflict of interest information for reviewers available on request
