Bile duct changes are atypical of autoimmune hepatitis. Our aims were to assess the frequency and significance of these changes in classical disease. Liver biopsy specimens were reviewed under code from 84 patients who satisfied international scoring criteria for autoimmune hepatitis, and the findings were correlated with clinical features and outcome. Twenty patients (24%) had biliary changes, including 6 with destructive cholangitis, 4 with ductopenia, and 10 with nondestructive cholangitis. Patients with and without bile duct changes had similar laboratory findings. Diagnostic scores for autoimmune hepatitis were lower in patients with bile duct changes (16.6 +/- 0.6 vs. 19.1 +/- 0.2, P <.0001). The frequencies of scores sufficient for a definite (80% vs. 97%, P =.03) or probable diagnosis (20% vs. 3%, P =.03) were also less in this group. Patients with destructive cholangitis and/or ductopenia responded as well to therapy as patients with nondestructive cholangitis, and outcomes in each group were similar to those of patients without biliary changes. We concluded that biliary changes can occur in classic autoimmune hepatitis, and they are not associated with distinctive clinical features or treatment response. They may be coincidental findings associated with classic disease or weak expressions of a variant syndrome. In the absence of a cholestatic clinical syndrome, they do not compel a different management strategy.