title: Antibiotic resistance of Helicobacter pylori in Mashhad, Iran.
abstract: OBJECTIVE
  To evaluate Helicobacter pylori resistance to amoxicillin, clarithromycin, metronidazole and tetracycline in Mashhad, Iran.
  
  
  METHODS
  The cross-sectional study was done from January to May 2008 in Mashhad, involving 185 patients who had been indicated for endoscopy and lesions had been found. Biopsy samples were assessed with histological evaluation, rapid urease test, and culture. Antibiotic resistance was assessed by the disc diffusion method. Data was analysed with SPSS 11.5 using chi-square and Fisher's exact test. P values of < 0.05 were regarded as statistically significant.
  
  
  RESULTS
  Of the total patients, histological evaluations were positive in 124 (67%). Compared with histology, sensitivity and specificity of rapid urease test were 96.7% and 100%, respectively. In 82 (66.1%) patients with positive cultures, antibiotic resistance was found in 14 (17.1%) for clarithromycin; 53 (64.6%) for metronidazole; and 8 (9.8%) for amoxicillin. No resistance was observed for tetracycline. Moreover, 9 (64%) patients with resistance to clarithromycin had co-resistance to metronidazole.
  
  
  CONCLUSIONS
  Metronidazole is not recommended for treatment of Helicobacter pylori as a first-line drug. Also, considering the sensitivity and specificity of rapid urease test, we suggest this method as a suitable alternative for histology.
authors.affiliation: Lorestan University of Medical Sciences, Mashhad University of Medical Sciences, Iran.
authors.forename: Abolfazl
authors.initials: A
authors.lastname: Zendedel
authors.forename: Farideh
authors.initials: F
authors.lastname: Moradimoghadam
authors.forename: Vahid
authors.initials: V
authors.lastname: Almasi
authors.forename: Hamidreza
authors.initials: H
authors.lastname: Zivarifar
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000658:Amoxicillin / Q000627:therapeutic use; D016009:Chi-Square Distribution; D017291:Clarithromycin / Q000627:therapeutic use; D003430:Cross-Sectional Studies; D004352:Drug Resistance, Microbial; D005260:Female; D016481:Helicobacter Infections / Q000175:diagnosis / Q000188:drug therapy*; D016480:Helicobacter pylori / Q000187:drug effects*; D006801:Humans; D007492:Iran; D008297:Male; D008795:Metronidazole / Q000627:therapeutic use; D008875:Middle Aged; D012680:Sensitivity and Specificity; D013752:Tetracycline / Q000627:therapeutic use; D014510:Urease
chemical_list: D008795:Metronidazole; D000658:Amoxicillin; D014510:Urease; D013752:Tetracycline; D017291:Clarithromycin