title: A Viral Mechanism in Acute Exacerbations of Chronic Type B Hepatitis: Hepatitis B Virus Reinfection and Subsequent Reactivation of Two Viral Strains.
abstract: Chronic hepatitis B virus (HBV) infections are frequently associated with exacerbations of hepatitis of which the majority are due to reactivation of viral activity. Variation in a viral genome during persistent infection has been shown to be a possible cause for reactivation. In this study, we have found another possible mechanism. HBV in a patient with repeated exacerbations was isolated at six different times during follow-up and was characterized by polymerase chain reaction and DNA sequencing. The first episode of exacerbation was accompanied with increased replication of an HBV strain. The second episode, however, was associated with the sudden appearance of an HBV strain that displayed enough sequence variations to warrant the designation as a separate strain. The results suggested a reinfection event by another independent HBV. Subsequent exacerbations were then related to coactivation of both viral strains. These observations provide significant information toward understanding the acute exacerbations of chronic type B hepatitis. Copyright 2001 S. Karger AG, Basel
authors.affiliation: Graduate Institute of Clinical Medicine and Department of Internal Medicine, College of Medicine, National Taiwan University Hospital, Taipei, Taiwan, ROC.
authors.forename: P.J.
authors.initials: PJ
authors.lastname: Chen
authors.forename: M.L.
authors.initials: ML
authors.lastname: Chen
authors.forename: D.S.
authors.initials: DS
authors.lastname: Chen