The molecular analysis performed in an HIV-hepatitis B virus (HBV) coinfected patient revealed selection of an unusual HBV polymerase mutation (rtV191I) during tenofovir-containing therapy, conferring simultaneously immune escape by HBsAg negativity and resistance to lamivudine but not tenofovir. Phenotypic analysis revealed impaired replicative capacity of mutants, which could be restored by concomitant precore or basal core promoter mutations (HBe-antigen-negativity). HBV mutants carrying drug and vaccine resistance may represent a considerable individual risk and public health concern.
aDepartment of Medicine III, University Hospital Aachen, Germany
bHospital Carlos III, Madrid, Spain
cInfektiologikum, Frankfurt, Germany.
Received 7 September, 2008
Revised 17 September, 2008
Accepted 12 November, 2008
Correspondence to Frank Tacke, MD, PhD, Department of Medicine III, RWTH-University Hospital Aachen, Pauwelsstraße 30, 52074 Aachen, Germany. Tel: +49 241 80 35848; fax: +49 241 80 82455; e-mail: firstname.lastname@example.org