[IgM class antibodies against hepatitis A viruses in the differentiation of viral hepatitis].

The sera of 64 patients with acute viral hepatitis which were previously HbsAG negative by rPHA were tested by RIA methods for the presence of HBsAG and anti-HBc, by EIA method for HBc and anti-HBc and also by RIA method for the presence of IgM antibodies against hepatitis A virus. The pairs of sera were tested also for the presence of antibodies against cytomegalovirus and EB viruses. Of the total of 64 patients, markers of fresh HB viral infection were proved in 5 patients, sera positive to IgM antibodies to hepatitis A virus were found in 51 and no positive tests to any of the tested viruses were found in 8. The authors consider that they belonged to "non-A, non-B" viral hepatitis.