Comparative study of chronic hepatitis: histological differences between Japan and England.

A comparative study of chronic hepatitis in two hospitals in Japan and England is reported. Patients seen in England came from a variety of countries and races. Type B chronic hepatitis was common in both hospitals. While CPH, CLH, and mild CAH were more frequently seen in cases from England, two thirds of the cases from Japan showed moderate or severe CAH. The most striking differences among the histological features were plasma cell infiltration and lymphoid follicle formation. The former was more frequent and conspicuous in cases from England, and the latter in non-A non-B cases from Japan. The incidence of bile duct damage and granulomatous lesions was different in the two hospitals. It was concluded that geographical differences should be taken into account when pathogenesis, histological definition, treatment and many other aspects of chronic hepatitis are assessed.