Isoenzymes of Liver Alkaline Phosphatase in Serum of Patients with Hepatobiliary Disorders

Abstract

Abstract The isoenzymes of alkaline phosphatase (ALP; EC 3.1.3.1) present in the [unknown]sera of 116 patients with hepatobiliary disease were studied by electrophoresis on cellulose acetate. Individual liver isoenzyme bands were identified and quantitated by densitometric scanning. The occurrence and magnitude of increase of the isoenzyme bands of liver ALP (α2 alone or α1 and α2) are related to diagnosis. Of the cases studied, 30% showed only the α2 band of liver ALP. A couplet of liver isoenzyme bands (α1 and α2) was seen in 70% of the cases studied. The isolated α2 band occurred in 26 of 36 patients with viral hepatitis and in two patients with hepatic infarction. Most patients with other liver diseases showed the α1 and α2 couplet. The serum pattern of liver ALP is related to total ALP, age, ABO blood group, and serum bilirubin concentration. The α1 band is markedly increased in patients with granulomatous hepatitis and carcinoma metastatic to the liver. The findings are related to previous work, and their implications are discussed.