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From: Brian Symonds <[log in to unmask]> Laboratory Test Results, Alkaline Phosphatase Laboratory test results can be difficult to interpret. The reasons for this include the techinical way they are done, the complex nature of the biochemistry of the human body, and what the "normal" range of the test means. An abnormal test result may mean that you are sick, that you are well but the test result is normal for you, that you are well but your biochemistry doesn't match the population from which the range of normals was taken, that you are well but were engaged in activities before the test was done that caused it to be abnormal, or that the test was not done technically correctly. Generally tests are ordered to detect or exclude the possibility of a disease, to confirm the presence of a disease, to classify the type of disease, and to monitor a patient's progress or response to therapy. However, for some tests, it is cheaper in the lab to do a whole bunch at once than to do them individually. Thus when a specific test is needed, the doctor may get a report back with 19 other test results that weren't needed (a Chem 20). If one of those is abnormal, the question always arises as to what it means, and what should be done about it (if anything). Spurious results usually lead to more testing which may lead to more spurious results and so on. In Canada, governments have found that it is more expensive to do a Chem 20 and have to follow up on abnormal results that don't mean anything, than it is for doctors to just order the specific test they want and get only that result back, so there are no Chem 6s or 12s or 20s here anymore. Your doctor always interprets test results in conjunction with what he/she knows about you and your body. It is thus somewhat difficult to answer the question as to what an abnormal test result means because it is being taken in isolation, and what it means in general may not mean anything to you specifically. Alkaline phosphatase is a test that has been promoted by many for a dubious achievement award for being notoriously frequently abnormal with, upon further investigation, no abnormalities being found to account for the abnormal result. If blood is refrigerated before it is tested, the blood sample will give a high Alk Phos reading. It is often slightly high for no apparent reason, especially in the elderly, but on the other hand, numerous diseases can cause it to become elevated. Because elevated Alk Phos may be one indicator of some types of cancer, in the past, its elevation has triggered many wild goose chases looking for cancer when it did not exist. These days, most clinicians, in the absence of any obvious cause of the elevation, will repeat the test on subsequent scheduled checkups. This gives a series of snapshots over time of how the test and the person are doing, so that unnecessary testing can be avoided. However, if the test becomes increasingly elevated over a short time, further testing is definitely indicated. Alkaline phospatase is produced by cells lining the bile tract, in bone, in the bowel, in the kidney, and the placenta in pregnancy. In people older than 50, a level of up to 1.5 times the usual "normal" is not unusual. People with certain blood types (B or O) will have an elevation of this test after eating a fatty meal. While an elevated Alk Phos level is common in some types of liver disease states (infection, congestion, gallstones, inflammatory liver diseases, autoimmune liver diseases, chemical injury diseases, and cancer for example), it can also occur in congestive heart failure, stomache ulcers, diabetes, thyroid disease, bone diseases, and kidney diseases. The use of some drugs (Alcohol, L-DOPA, Bromocriptine, and a whole host of others) can also cause it to be elevated.