[Hepatitis non-A, non-B-associated substance in stool from patients with posttransfusion and sporadic hepatitis].

A hepatitis non-A,non-B-associated substance (HNANB-AS) excreted in feces has been detected by means of a sandwich radioimmunoassay using reconvalescent serum and IgG from patients with posttransfusion HNANB. 4380 stool filtrates from 1599 patients were screened with this assay. In patients with posttransfusion or sporadic acute and chronic HNANB the substance was detected with a mean frequency of 34%, in acute posttransfusion HNANB, where samples were screened at the beginning of the clinical symptoms, 71.4% of stool specimens were positive for HNANB-AS. A high frequency of positive results was found in patients undergoing dialysis (31.3%), hemophiliacs (16.6%) and patients with cryptogenic cirrhosis (16%). Positive specimens were seen in hepatitis A (7.1%), acute and chronic HBV-infection (9.6%), various liver diseases (7.8%), outpatients of a physician (3.1%) and clinical or laboratory staff (6%). In these groups, too, anamnestic data speaking in favour for a possible HNANB frequently were obtained. The discovery of a partially double-stranded circular DNA of 5.0 Kb in HNANB-AS which sequence differs from human, bacterial and known viral DNA, argues the presence of a viral particle in stools of patients with sporadic and parenteral HNANB.