title: The study of mutation in 23S rRNA resistance gene of Helicobacter pylori to clarithromycin in patients with gastrointestinal disorders in Isfahan - Iran.
abstract: BACKGROUND
  Helicobacter pylori antimicrobial resistance is an important factor responsible for treatment failure. The purpose of this study was evaluating the prevalence of point mutations in clarithromycin-resistant clinical isolates of H. pylori in Isfahan city of Iran.
  
  
  METHODS
  Thirty isolates of H. pylori from 130 biopsy specimens were isolated by culture and confirmed by biochemical and PCR tests. The MIC of clarithromycin antibiotic for 30 clinical isolates of H. pylori was determined by E-test method. The point mutations in the 288 bp of 23S rRNA gene of H. pylori were investigated in four clarithromycin-resistant clinical isolates by PCR followed by sequencing.
  
  
  RESULTS
  Among 30 isolates of H. pylori, 4 cases were resistant to clarithromycin. One point mutation was found at position T2243C in the 23S rRNA gene in all resistance isolates.
  
  
  CONCLUSIONS
  In our study, H. pylori resistance to clarithromycin associated with point mutation at position 2243 (T2243C).
authors.affiliation: Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Farzad
authors.initials: F
authors.lastname: Khademi
authors.affiliation: Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Jamshid
authors.initials: J
authors.lastname: Faghri
authors.affiliation: Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Sharareh
authors.initials: S
authors.lastname: Moghim
authors.affiliation: Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Bahram Nasr
authors.initials: BN
authors.lastname: Esfahani
authors.affiliation: Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Hossein
authors.initials: H
authors.lastname: Fazeli
authors.affiliation: Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Farkhondeh
authors.initials: F
authors.lastname: Poursina
authors.affiliation: Department of Gastroenterology, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Peyman
authors.initials: P
authors.lastname: Adibi
authors.affiliation: Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Masoumeh
authors.initials: M
authors.lastname: Madhi
authors.affiliation: Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Hajieh Ghasemian
authors.initials: HG
authors.lastname: Safaei
keywords: Clarithromycin resistance; Helicobacter pylori; point mutations