title: Hepatitis B virus (HBV) reactivation after cytotoxic or immunosuppressive therapy--pathogenesis and management.
abstract: In an endemic area for chronic hepatitis B infection, reactivation of this virus is a serious cause of morbidity and mortality in patients undergoing cytotoxic or immunosuppressive therapy. Careful prospective serological testing has shown that hepatitis B virus reactivation is a two-staged process. The initial stage occurs during intense cytotoxic or immunosuppressive therapy and is characterised by enhanced viral replication, as reflected by increases in the serum levels of hepatitis B virus DNA, hepatitis B e antigen, hepatitis B virus DNA polymerase and infection of naïve hepatocytes with hepatitis B virus. The second stage is related to restoration of immune function following withdrawal of cytotoxic or immunosuppressive therapy, which causes rapid immune-mediated destruction of infected hepatocytes. Clinically, this can lead to hepatitis, hepatic failure and even death. The occurrence and severity of hepatitis B virus reactivation after various cytotoxic or immunosuppressive therapy is unpredictable and treatment has been disappointing, largely due to the late administration of therapy. Recently, pre-emptive treatment of chronic hepatitis B patients undergoing cytotoxic or immunosuppressive therapy, with potent nucleoside analogues has shown some promising results. Further controlled studies are needed to define the incidence and risk factors of hepatitis B reactivation so that pre-emptive treatment with nucleoside analogues could be administered to those patients at high risk of disease.
authors.affiliation: University Department of Medicine, Queen Mary Hospital, 102 Pokfulum Road, Hong Kong SAR, China.
authors.forename: L
authors.initials: L
authors.lastname: Xunrong
authors.forename: A W
authors.initials: AW
authors.lastname: Yan
authors.forename: R
authors.initials: R
authors.lastname: Liang
authors.forename: G K
authors.initials: GK
authors.lastname: Lau
mesh_terms: D000970:Antineoplastic Agents / Q000009:adverse effects*; D000998:Antiviral Agents / Q000627:therapeutic use*; D004258:DNA Polymerase III / Q000097:blood; D004279:DNA, Viral / Q000097:blood; D006513:Hepatitis B e Antigens / Q000097:blood; D006515:Hepatitis B virus / Q000187:drug effects / Q000254:growth & development*; D019694:Hepatitis B, Chronic / Q000188:drug therapy* / Q000821:virology*; D006801:Humans; D007166:Immunosuppressive Agents / Q000009:adverse effects*; D012008:Recurrence; D014775:Virus Activation / Q000187:drug effects*
chemical_list: D000970:Antineoplastic Agents; D000998:Antiviral Agents; D004279:DNA, Viral; D006513:Hepatitis B e Antigens; D007166:Immunosuppressive Agents; C065639:DNA polymerase A; D004258:DNA Polymerase III