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

Background/Aims: In approximately 5% of chronic liver disease cases, no aetiology can be identified. We selected sera from 50 patients with chronic hepatitis of unknown aetiology who were enrolled in this follow-up study whose aim is to gain insight into the possible role of viruses and to define potential clinical outcomes. Methods: Patients' sera were screened with highly sensitive polymerase chain 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 15/50 (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 of chronic hepatitis cases of unknown aetiology, Improved HBV detection tests, which appear mandatory for the diagnosis and management of non-A non-E hepatitis as well as for improved safety of transfusions and transplantations are needed. (C) 2001 European Association for the Study of the Liver. Published by Elsevier Science B,V, All rights reserved.