The Incidence of Chronic Active Hepatitis in Norway: A Retrospective Study

Abstract

From all departments of internals medicine in Norway information has been collected about new cases of chronic active hepatitis (CAH) diagnosed during 1981. A questionnaire together with copies of histological examination reports and discharge summaries have been carefully examined to ensure that established diagnostic criteria were fulfilled. Of the 63 reported cases, 58 were recorded as CAH. An etiological agent was identified in 9 cases: 6 were [hepatitis .beta. surface antigen] HBsAg-positive, 2 were alcohol-induced and 1 drug-induced. The other 49 cases were assumed to be idiopathic. The incidence of CAH of all causes was 1.41/100.000; of idiopathic CAH, 1.19/100,000; and of HBsAg-positive CAH, 0.15/100.00. The mean age was 51 yr. and a 3rd of the patients in the idiopathic group were 65 yr or older at presentation. In this group about 71% of the patients had autoantibodies, and 61% had serum aminotransferase levels more than 5 times and 46% more than 10 times the upper reference range. The proportion of the different aetiological agents was different from what was previously reported. The activity of the disease, judged by the serum level of aminotransferase, was more pronounced than reported in other investigations. Apparently, only relatively severe cases of CAH were subjected to liver biopsy.