Post-transfusion hepatitis type non-A, non-B in southern Sweden: occurrence and clinical significance.

Two prospective studies of the occurrence and clinical significance of post-transfusion hepatitis non-A, non-B were performed in Malmö, Sweden. In both studies, patients of a broad clinical spectrum were followed up 6 and 12 weeks after transfusion. In a 7 week study from 1983, hepatitis non-A, non-B occurred in 9/173 transfused patients (5.2%) versus 1/203 untransfused controls (0.5%) (p less than 0.01). In a 6 month study from 1984-85, the incidence of hepatitis non-A, non-B had declined to 2.4% (18/739 transfused patients). The mean number of transfused units was about 5 in both studies and most patients had subclinical disease. Despite similar transfusion volumes to patients above or below 70 years of age, hepatitis non-A, non-B was predominantly seen among patients less than 70 years. In the 1984-85 study, hepatitis non-A, non-B incidence was 1.2% in recipients greater than or equal to 70 years, 3.4% in recipients less than 70 years and 4.5% in recipients less than 40 years. One year after the initial hepatitis non-A, non-B episode, 4/18 patients (22%) had biochemical signs of chronic hepatitis.