title: [Prevalence of Helicobacter pylori resistant to clarithromycin, amoxicillin and metronidazole in children].
abstract: OBJECTIVE
  To investigate the prevalence of Helicobacter pylori (Hp) resistant to clarithromycin, amoxicillin and metronidazole in children.
  
  
  METHODS
  A total of 44 Hp clinical isolates were cultured from children patients with Hp gastritis and peptic ulcer who underwent gastroscopy during the period from October 2002 to November 2003 in Children's Hospital affiliated to Medical College of Zhejiang University. Nineteen of the patients were girls and 25 boys. The mean age was 8.66 +/- 2.66 years (3 approximately 14 years). The susceptibilities of the 44 Hp strains to clarithromycin, amoxicillin and metronidazole were tested by agar dilution test to determine minimum inhibitory concentration (MIC)(50), MIC(90) and resistance rates were also calculated.
  
  
  RESULTS
  Among the 44 Hp strains isolated from children, 8, 4, and 14 strains were resistant to clarithromycin, amoxicillin and metronidazole and the resistant rate was 18.2% (8/44), 9.1% (4/44) and 31.8% (14/44), with MICs for all strains ranging from < 0.125 microg/ml to 64 microg/ml, < 0.125 microg/ml to 64 microg/ml and < 0.125 microg/ml to 128 microg/ml, respectively. MIC(50) and MIC(90) of clarithromycin, amoxicillin and metronidazole were < 0.125 microg/ml, 8 microg/ml; < 0.125 microg/ml, 0.5 microg/ml; 0.5 microg/ml, 128 microg/ml, respectively. The prevalence of Hp resistant to clarithromycin was higher in children than that in adults, while to metronidazole was lower than that in adults with high MICs (32 - 128 microg/ml) and MIC(90) (128 microg/ml) of metronidazole for resistant isolates. Three multidrug resistant strains (6.8%) were simultaneously resistant to these three antibiotics.
  
  
  CONCLUSIONS
  The prevalence of Helicobacter pylori resistant to metronidazole was high in children, and the rate of resistance to clarithromycin was higher than that isolated from adults. Amoxicillin-resistant strains were now found, and multidrug resistant strains which resistant to the three antibiotics also emerged.
authors.affiliation: Department of Gastroenterology, Children's Hospital Affiliated to Medical College, Zhejiang University, Hangzhou 310003, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Chen
authors.forename: Fei-bo
authors.initials: FB
authors.lastname: Chen
authors.forename: Jin-dan
authors.initials: JD
authors.lastname: Yu
authors.forename: Xue-jun
authors.initials: XJ
authors.lastname: Chen
authors.forename: Zhong-yue
authors.initials: ZY
authors.lastname: Li
authors.forename: Xu-ping
authors.initials: XP
authors.lastname: Zhang
mesh_terms: D000293:Adolescent; D000658:Amoxicillin / Q000494:pharmacology*; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002648:Child; D002675:Child, Preschool; D017291:Clarithromycin / Q000494:pharmacology*; D024901:Drug Resistance, Multiple, Bacterial; D005260:Female; D005756:Gastritis / Q000382:microbiology; D005773:Gastroscopy; D016480:Helicobacter pylori / Q000187:drug effects* / Q000302:isolation & purification; D006801:Humans; D008297:Male; D008795:Metronidazole / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D010437:Peptic Ulcer / Q000382:microbiology; D015995:Prevalence
chemical_list: D000900:Anti-Bacterial Agents; D008795:Metronidazole; D000658:Amoxicillin; D017291:Clarithromycin