['Previous studies have suggested an association of viral hepatitis with alcoholism, although the role of confounding risk factors (e.g. i.v. drug use) has not been adequately excluded. We therefore compared the seroprevalences of hepatitis B and C in alcoholic patients to that of a nonalcoholic control group.', 'Hepatitis B surface antigen, hepatitis B core antibody, hepatitis B surface antibody, and hepatitis C virus antibody testing (second generation ELISA and a confirmatory recombinant immunoblot assay) was performed in 150 consecutive alcoholics admitted for detoxification and in 166 randomly selected patients attending a general medical clinic who were screened for alcoholism.', 'Hepatitis B and C seropositivities in actively drinking alcoholics are 49.3 and 35.3%, respectively, and were significantly associated with a history of i.v. drug abuse. Out of 166 general medicine clinics patients, 93 were classified as nonalcoholic (by both self-report and collateral verification), 46 patients had a history of alcoholism , and 27 were indeterminate. In the subgroup of patients without known viral hepatitis risk factors, there was no significant difference in hepatitis B seropositivity among nonalcoholic general medicine clinic patients, alcoholic general medicine clinic patients, and alcoholic patients admitted for detoxification (22.1%, 30.3%, and 27.6%, respectively). In contrast, anti-HCV recombinant immunoblot assay seropositivity in alcohol patients admitted for detoxification without risk factors was significantly greater than in nonalcoholic general medicine patients without risk factors (10 vs 0%, p >0.01). Stepwise logistic regression analysis revealed that alcoholism requiring detoxification was a significant risk factor for hepatitis C but not for hepatitis B seropositivity.'] Is alcoholism associated with hepatitis C but not hepatitis B in an urban population?