Quantification of bone alkaline phosphatase in serum by precipitation with wheat-germ lectin: a simplified method and its clinical plausibility.

We report an easy, rapid method for quantifying bone isoenzyme of alkaline phosphatase (EC 3.1.3.1., ALP) in serum. The original method described by Rosalki and Ying Foo (Clin Chem 1984;30:1182-6) was somewhat simplified. In contrast to their results, we found that bone ALP is precipitated quantitatively by wheat-germ lectin. To check the clinical plausibility of the method, we used samples from several comparison groups (blood donors, children, pregnant women, patients with neoplasms but without skeletal involvement) and a large number of patients suffering from bone diseases and diseases of the liver and biliary tree. Measured activities of bone ALP nearly always correlated with the clinical diagnosis. Only patients with hepatitis often had pathological bone activities not in accord with the other findings. Possible reasons for this observation are discussed.