Background: Reactivation of occult hepatitis B virus (HBV) infection is a well-known complication of cytotoxic chemotherapy. Lamivudine prophylaxis is recommended to reduce the incidence and severity of hepatitis in this context.
Case report: An HIV-infected patient positive for HBs antigen became positive for HBc antibody alone under lamivudine given as part of antiretroviral therapy. He was treated with chemotherapy for non-Hodgkin's lymphoma while under lamivudine. Then, he developed HBV-related hepatitis that led to delay chemotherapy. He received adefovir that induced a dramatic decline in HBV DNA load and a normalisation of hepatic enzyme levels. However, the patient died of a relapse of lymphoma. Retrospective analysis of stored plasma samples showed evidence of lamivudine-resistant occult hepatitis before the onset of chemotherapy and reactivation of the HBV mutant.
Conclusion: To our knowledge, this is the first report of occult hepatitis reactivation due to lamivudine-resistant mutant selected under lamivudine therapy in an HIV-infected patient. Our study underlines the need to carefully investigate lamivudine resistance in HIV-infected patients with occult infection under lamivudine therapy. Those patients should be monitored with the addition of anti-viral agents effective against the mutant strain.