[Diagnostic value of alkaline phosphatase isoenzymes]

Among the serum enzymes used for diagnostic purposes the alkaline phosphatase (AP) is one of the oldest and the most frequently applied laboratory tests. Increased activity found in the serum is a consequence of certain hepato-biliary disorders, different bone diseases, endocrine syndromes, kidney illnesses and malignant tumors as well. From the study of the pattern of the isoenzymes of the serum-AP information of practical importance may be gained by which many differential-diagnostic problems can be solved. For the clinical-chemical laboratories methods that use electrophoretic separation on different membranes or gels are recommended. Patterns characteristic for different diseases may well be differentiated from normal constellation. AP-isoenzymes help to reveal cholestases at early stages, some disorders of bone metabolism and malignant processes as well.