title: Redetection of HBV lamivudine-resistant mutations in a patient under entecavir therapy, who had been treated sequentially with nucleos(t)ide analogues.
abstract: Development of hepatitis B virus (HBV)-resistant strains following nucleos(t)ide analog treatment is a major medical concern. This report describes a case of an adult patient with chronic HBV infection, sequentially treated with the nucleos(t)ide analogues, lamivudine, adefovir, and entecavir. During monotherapy with lamivudine, the patient developed lamivudine-resistant variants, which were undetectable during adefovir dipivoxil monotherapy. Twenty-two months after discontinuing lamivudine therapy, the resistant variants were again detected while the patient was receiving entecavir monotherapy. Genotypic analysis by sequencing the HBV polymerase was confirmed with the INNO-LiPA method. The results of this study suggest that entecavir treatment reselected residual lamivudine-resistant HBV variants, possibly because lamivudine-resistant HBV is less susceptible to entecavir than the wild-type virus. Despite the presence of these variants, the patient has had a complete virological response.
authors.affiliation: Department of Biochemistry, Hospital Universitario Vall d'Hebron, Barcelona, Spain.
authors.forename: Francisco
authors.initials: F
authors.lastname: Rodriguez-Frias
authors.forename: Rosendo
authors.initials: R
authors.lastname: Jardi
authors.forename: Melanie
authors.initials: M
authors.lastname: Schaper
authors.forename: Montserrat
authors.initials: M
authors.lastname: Gimferrer
authors.forename: Ioannis
authors.initials: I
authors.lastname: Elefsiniotis
authors.forename: David
authors.initials: D
authors.lastname: Tabernero
authors.forename: Rafael
authors.initials: R
authors.lastname: Esteban
authors.forename: Maria
authors.initials: M
authors.lastname: Buti
mesh_terms: D000225:Adenine / Q000008:administration & dosage / Q000031:analogs & derivatives / Q000627:therapeutic use; D000328:Adult; D000998:Antiviral Agents / Q000494:pharmacology / Q000627:therapeutic use; D004334:Drug Administration Schedule; D024882:Drug Resistance, Viral / Q000235:genetics*; D006147:Guanine / Q000031:analogs & derivatives* / Q000627:therapeutic use; D006515:Hepatitis B virus / Q000187:drug effects* / Q000235:genetics; D019694:Hepatitis B, Chronic / Q000188:drug therapy* / Q000821:virology; D006801:Humans; D019259:Lamivudine / Q000494:pharmacology*; D008297:Male; D009154:Mutation; D063065:Organophosphonates / Q000008:administration & dosage / Q000627:therapeutic use; D018894:Reverse Transcriptase Inhibitors / Q000494:pharmacology / Q000627:therapeutic use
chemical_list: D000998:Antiviral Agents; D063065:Organophosphonates; D018894:Reverse Transcriptase Inhibitors; D019259:Lamivudine; C413685:entecavir; D006147:Guanine; C053001:adefovir; D000225:Adenine