title: HBV resistant to lamivudine: experimental and clinical studies.
abstract: OBJECTIVE
  To identify the impact of lamivudine on HBV e antigen (HBeAg) seroconversion and HBV DNA level, and the appearance of Tyr-Met-Asn-Asp (YMDD) resistants.
  
  
  METHODS
  Forty-seven hepatitis B patients were treated with oral lamivudine. ALT level and HBeAg were detected in the treatment on the zero, 3rd, 6th and 9th month respectively. The levels of HBV DNA and YMDD resistants were analyzed with PCR microplate hybridization-ELISA.
  
  
  RESULTS
  After 9 months of treatment, HBV DNA became negative and ALT level was normal in 74% patients. Among these patients, 17% patients had HBeAg converted to negative and anti-HBe antibody positive, whereas another 15% patients showed HBeAg negative. YMDD resistants appeared in 19% patients (9/47). One, three and five resistants were detected in the treatment on the 3rd, 6th and 9th month respectively.
  
  
  CONCLUSIONS
  Most HBV DNA in serum became negative after 9 months of treatment, and the rate of HBeAg seroconversion was 17% (HBV DNA level was lower than 100 pg/ml before treatment). YMDD resistants appeared in 19% patients.
authors: Department of Clinical Laboratory Medicine,Guangdong Provincial Hospital of Traditional Chinese Medicine, Guangzhou 510120, China. zhoudongyao@21cn.com
authors: Dong-Yao
authors: DY
authors: Zhou
authors: Yong-Jian
authors: YJ
authors: Cao
authors: Lian-Ying
authors: LY
authors: Lin
authors: Hong
authors: H
authors: Wang
authors: Jian-Sheng
authors: JS
authors: Huang
mesh_terms: D000410:Alanine Transaminase / Q000097:blood; D004279:DNA, Viral / Q000097:blood; D004259:DNA-Directed DNA Polymerase / Q000235:genetics; D004351:Drug Resistance; D006508:Hepatitis Antibodies / Q000097:blood; D006509:Hepatitis B / Q000097:blood / Q000188:drug therapy* / Q000276:immunology / Q000821:virology*; D006513:Hepatitis B e Antigens / Q000032:analysis / Q000276:immunology; D006515:Hepatitis B virus / Q000187:drug effects* / Q000235:genetics / Q000276:immunology / Q000502:physiology*; D006801:Humans; D019259:Lamivudine / Q000627:therapeutic use*; D009154:Mutation; D018894:Reverse Transcriptase Inhibitors / Q000627:therapeutic use*; D013997:Time Factors
chemical_list: D004279:DNA, Viral; D006508:Hepatitis Antibodies; D006513:Hepatitis B e Antigens; D018894:Reverse Transcriptase Inhibitors; D019259:Lamivudine; D000410:Alanine Transaminase; D004259:DNA-Directed DNA Polymerase