High incidence of hepatitis B infections among chronic hepatitis cases of unknown aetiology

Background/Aims: In approximately 5% of chronic liver disease cases, no aet iology can be identified. We selected sera from 50 patients with chronic he patitis of unknown aetiology who were enrolled in this follow-up study whos e aim is to gain insight into the possible role of viruses and to define po tential clinical outcomes. Methods: Patients' sera were screened with highly sensitive polymerase chai n reaction assays for hepatitis B (HBV), C, D, and G viruses and TT virus. Sera were also retested for antibodies against the core antigen of HBV. Results: Surprisingly, HBV DNA was detected in both serum and liver in 15/5 0 (30%) patients. Immunostaining for HBV antigens on biopsies from patients positive for HBV DNA showed HBcAg and/or HBsAg expression at low levels in 9/15 samples. Eleven of the fifteen patients were anti-HBc positive. With one exception, all patients carried HBV genomes at low levels (10(4) copies /ml or less), Histological signs of chronic liver disease were observed in all patients. Conclusion: Unrecognised HBV infections may account for a high proportion o f chronic hepatitis cases of unknown aetiology, Improved HBV detection test s, which appear mandatory for the diagnosis and management of non-A non-E h epatitis as well as for improved safety of transfusions and transplantation s are needed. (C) 2001 European Association for the Study of the Liver. Published by Else vier Science B,V, All rights reserved.