An alkaline phosphatase (ALP) level test
measures the amount of alkaline phosphatase enzyme in your bloodstream. Enzymes
are proteins that help chemical reactions happen. For instance, they can break
big molecules down into smaller parts, or they can help smaller molecules join
to form bigger structures.
The alkaline phosphatase test is usually
performed to diagnose conditions associated with the hepatobiliary system (the
liver, bile ducts and the gallbladder) or bone disease. Diseases that destroy
the cells of organs containing alkaline phosphatase lead to the release of ALP
into the blood, which raises the blood level of alkaline phosphatase.
The normal range of ALP varies from person
to person and depends on your age, blood type, gender, and whether you’re
The normal range for serum ALP level is 20 to 140 IU/L, but this can vary from
laboratory to laboratory. The normal range runs higher in children and
decreases with age.
Higher-than-normal levels of ALP in your blood may indicate a problem with your liver
or gallbladder. This could include hepatitis, cirrhosis, liver cancer,
gallstones, or a blockage in your bile ducts.
High levels may also indicate an issue
related to the bones such as rickets, Paget’s disease, bone cancer, or an
overactive parathyroid gland. In rare cases, high ALP levels can indicate heart
failure, kidney cancer, other cancer, mononucleosis, or bacterial infection.
If your ALP level is high, your doctor may
have you take another test, called an ALP isoenzyme test, to determine whether
the alkaline phosphatase in your blood is coming from your liver or your bones.
ALP levels in your blood is rare, but it can indicate malnutrition, which
could be caused by celiac disease or a deficiency in certain vitamins and
The best way to know what is normal or not is to discuss the results with your doctor, who will be able to interpret the lab’s specific result and reference ranges.
Keyword: alkaline phosphatase (ALP) level