BIOTINIDASE ACTIVITY IN PATIENTS WITH LIVER-DISEASE

To investigate whether biotinidase deficiency may occur in liver disea se, we determined biotinidase activity, biotin levels, and organic aci ds in patients with liver disease. Serum biotinidase activity in patie nts with liver disease (2.63 +/- 1.40 nmol/min/ml) was significantly l ower than in the control group (5.43 +/- 1.06 nmol/min/ml). Serum biot inidase activity in decompensated liver cirrhosis (LC) and hepatoma wa s significantly lower than in acute viral hepatitis (AVH), chronic vir al hepatitis (CVH), and compensated LC. The mean serum level of biotin in decompensated LC (1.8 +/- 0.6 mug/ml) and hepatoma (1.7 +/- 0.8 mu g/ml) was significantly lower than in the control group (2.5 +/- 1.0 m ug/ml), and urinary excretion of biotin was increased in patients with liver disease, particularly in decompensated LC. Biotinidase activity correlated positively with serum biotin level and correlated negative ly with urinary biotin level. Moreover, in four of five patients with severe liver disease the excretion of propionate, lactate, and 3-hydro xybutyrate decreased after biotin supplementation. The data for patien ts with severe liver disease so resembled those for late-onset multipl e carboxylase deficiency that biotinidase deficiency is likely in pati ents with severe liver disease.