Abnormal vitamin D metabolism in patients with cirrhosis.

To assess the role of hepatic function and alcohol on vitamin D metabolism, serum 25-hydroxyvitamin D (25-OHD) levels were measured in 20 healthy nonalcoholic control subjects, 31 "inactive" cirrhotics whose alcoholism was in remission, 8 alcoholic cirrhotics, and 15 alcoholics with normal liver function. Cirrhosis but not alcoholism, was assoicated with low serum 25-OHD levels. The aminopyrine breath test (ABT) was performed because aminopyrine, like vitamin D3, is metabolized by hepatic microsomes; the ABT correlated highly (r = 0.74, rho less than 0.01) with serum 25-OHD in the inactive cirrhotics. After an intravenous injection of 120 mug vitamin D3, serum 25-OHD rose significantly within 24 hr in 6 healthy controls and 2 patients with celiac disease but not in 6 inactive cirrhotics. The data suggest impaired 25-hydroxylation of vitamin-D impaired in patients with cirrhosis, related predominantly to the degree of hepatic dysfunction.