Histologic study of chronic active hepatitis C; comparison with chronic active hepatitis B.

Reports on the histologic findings of chronic active hepatitis C (CAH-C) have been rare, and the characteristic histologic findings of CAH-C have been not yet determined. To compare the differences in the histologic findings between CAH-C and chronic active hepatitis B (CAH-B) group, we analyzed the histologic findings of 19 patients with CAH-C, who had positive tests for HCV-antibody by EIA, and 19 patients with CAH-B who had negative tests for HCV-antibody but positive tests for HBsAg by RIA. Histologic features were analyzed between the CAH-C and CAH-B groups using a scoring system which is modified from Knodell's histologic activity index-looking at portal inflammation, periportal necroinflammation, portal fibrosis, focal necrosis, regeneration, polyploid nuclear change, sinusoidal lymphocytic reaction and fatty change. Portal inflammatory cell infiltrations with prominent lymphocytes and follicular arrangement were more frequent in the CAH-C group (10 of 19 cases) than in the CAH-B group (5 of 19 cases). Severe sinusoidal lymphocytic reactions were also more prominent in the CAH-C group (11 of 19 cases) than in the CAH-B group (6 of 19 cases). However, periportal necroinflammation, portal fibrosis, focal hepatic necrosis, regeneration and polyploid nuclear changes were more prominent in the CAH-B group than in the CAH-C group. In conclusion, follicular portal inflammation and severe sinusoidal lymphocytic reactions were common histologic findings in serologically proven CAH-C when compared to CAH-B.