BETA-HEXOSAMINIDASE IN BILE AND PLASMA FROM PATIENTS WITH CHOLESTASIS

beta-Hexosaminidase (Hex) activity was determined in bile from 18 pati ents with cholestasis, six patients without cholestasis and in ten nor mal liver biopsies. The difference in the mean activities in bile from patients with and without cholestasis was not significant. Only about 0.5 promille of total liver Hex activity was lost per day via the bil e flow. Gel chromatography showed that enzyme forms present in bile ha d higher molecular weights than the forms present in liver tissue, ind icating that the biliary enzyme was not routed through the lysosomes b efore release into the bile. In 32 patients with cholestasis, plasma H ex was increased compared to controls, and correlated to bilirubin. Th e activity was significantly higher in patients with severe cholestasi s than in patients with less severe forms of cholestasis, but no signi ficant difference in Hex activity was observed between patients with b enign or malignant biliary obstruction. No significant difference was noted between patients with cholestasis for less than 1 week compared to those whose illness had lasted more than 1.5 weeks. The impact of b iliary obstruction on plasma Hex is further illustrated by the observa tion that decompression lowered plasma Hex as well as bilirubin and al kaline phosphatase.