title: [Clinical analysis of hepatitis B virus mutations related to adefovir dipivoxil among patients with chronic hepatitis B virus infection in eastern Zhejiang province].
abstract: OBJECTIVE
  To explore the clinical characteristics of hepatic B virus (HBV) mutations related to adefovir dipivoxil (ADV) among patients with chronic HBV infection in eastern Zhejiang province and provide some reference values on normative usage of antiviral drugs.
  
  
  METHODS
  The data of chronic HBV-infected patients with HBV mutations related to ADV (n = 88) and non-mutation (n = 202) from June 2008 to August 2010 were analyzed retrospectively. The gene resistance mutations of HBV P region were analyzed by gene sequencing. And the HBV genotypes, HBV serum markers, HBV DNA levels and liver imaging findings were also analyzed.
  
  
  RESULTS
  There were 9 cases with pre-existing mutations in 88 patients. The mutated sites were multiple and complicated. And the mutated sites related to other antiviral drugs were all accompanied by ADV-related mutations. The single mutated site was mostly at rtA181T (46.59%) and at rtV214A (11.36%). There were 27 cases (30.68%) with ≥ two mutated sites. The constituent ratios of males, end-stage liver diseases, complicated nonalcoholic fatty liver disease (NAFLD) and HBV genotype C infection in the mutation group were higher than those in the non-mutation group (P < 0.01, < 0.01, 0.019, 0.045). The average ages in the mutation group were also higher than those in the non-mutation group (P < 0.001). But the constituent ratios of HBeAg positivity and the levels of HBV DNA were lower (P = 0.002, 0.02).
  
  
  CONCLUSIONS
  There may be some cases with pre-existing ADV-related mutations in ADV treatment-naive patients. The mutated sites occur at multiple loci, mostly at rtA181T and rtV214A. The male patients and those with a longer history of HBV infection, HBeAg negativity, HBV genotype C infection, illness progression and complicated NAFLD may be more susceptible to mutation. It is important for patients to accept and implement standardized regimens of antiviral drugs so as to prevent resistance and avoid salvage therapy.
authors.affiliation: Research Institute of Hepatic Disease, Zhejiang, China. har1224@126.com
authors.forename: Ai-rong
authors.initials: AR
authors.lastname: Hu
authors.forename: Su-wen
authors.initials: SW
authors.lastname: Jiang
authors.forename: Ling
authors.initials: L
authors.lastname: Li
authors.forename: Shi-xiong
authors.initials: SX
authors.lastname: Ding
authors.forename: Yao-ren
authors.initials: YR
authors.lastname: Hu
authors.forename: Xiao-yue
authors.initials: XY
authors.lastname: Liang
mesh_terms: D000225:Adenine / Q000031:analogs & derivatives* / Q000494:pharmacology; D000293:Adolescent; D000328:Adult; D000368:Aged; D000998:Antiviral Agents / Q000494:pharmacology*; D002681:China / Q000453:epidemiology; D004279:DNA, Viral / Q000097:blood / Q000235:genetics; D024882:Drug Resistance, Viral / Q000235:genetics*; D005260:Female; D005838:Genotype; D006515:Hepatitis B virus / Q000187:drug effects* / Q000235:genetics; D019694:Hepatitis B, Chronic / Q000188:drug therapy / Q000453:epidemiology / Q000821:virology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation / Q000187:drug effects*; D063065:Organophosphonates / Q000494:pharmacology*; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D000998:Antiviral Agents; D004279:DNA, Viral; D063065:Organophosphonates; D000225:Adenine; C106812:adefovir dipivoxil