Analysis index

1 ml serum (Stability in serum at 4°C – 8°C: 7 days)

Women:

35 – 105 U/l

Men:

40 – 130 U/l

Children:

Please refer to findings report

Suspicion of cholestatic liver disease (with gamma-GT), diseases of the bone system, involvement of skeletal system as part of other underlying illnesses, i.e. malignant tumors, kidney diseases, osteomalacia, hyperparathyroidism, suspicion of hypophosphatasia

For a more precise differentiation of the cause of the AP increase (osseous or biliary), not only the evaluation of gamma-GT but also the analysis of the AP isoenzymes (see below) may be helpful.  

An isolated high alkaline phosphatase value may be caused by vitamin D deficiency.

An isolated low alkaline phosphatase value can indicate hypophosphatasia. On suspicion of this, pyridoxal phosphate should be evaluated for confirmation. This would typically be increased to at least 3-fold. Prerequisite for this is that a safe differentiation of pyridoxal and pyridoxal phosphate is metrologically possible. In case of decreased levels, differential diagnostically Celiac disease, M. Wilson, M. Cushing, hypothyroidism, milk-alkali syndrome, multiple myeloma, pronounced anemia, anorexia, heavy metal poisoning and fibrate medication should also be considered.