title: High rate of A2142G point mutation associated with clarithromycin resistance among Iranian Helicobacter pylori clinical isolates.
abstract: This study aimed to investigate the clarithromycin resistance and its associated molecular mechanisms among Helicobacter pylori isolates from dyspeptic patients in Shiraz, Iran. From January to May 2014, 100 H. pylori strains were isolated from patients with gastroduodenal disorders. The resistance to clarithromycin was quantitatively evaluated, using Epsilometer (E-test) method. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was performed on all the isolates to detect A2143G and A2142G mutations in 23S rRNA gene. The H. pylori isolation rate was found to be 31.4%. E-test showed that 20% of isolates were resistant to clarithromycin (MIC ≥ 1 mg/L). MIC of clarithromycin ranged between 0.016 and 24 mg/L. Findings of PCR-RFLP showed that the A2142G was the most (90%) frequently point mutation, followed by the A2143G (10%). No statistically significant difference was found between H. pylori clarithromycin resistance point mutations and patients' gender or age. To the best of our knowledge, this is the first report of high frequency of A2142G point mutation in Iran and probably in other regions of the world. Considering the increasing trend of H. pylori resistance to clarithromycin due to these mutations, it is crucial to investigate the new therapeutic approaches against H. pylori infection.
authors.affiliation: Department of Bacteriology and Virology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Reza
authors.initials: R
authors.lastname: Khashei
authors.affiliation: Department of Bacteriology and Virology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Mahintaj
authors.initials: M
authors.lastname: Dara
authors.affiliation: Department of Bacteriology and Virology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Abdollah
authors.initials: A
authors.lastname: Bazargani
authors.affiliation: Department of Internal Medicine, Gastroenterology Ward, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Kamran
authors.initials: K
authors.lastname: Bagheri Lankarani
authors.affiliation: Department of Internal Medicine, Gastroenterology Ward, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Alireza
authors.initials: A
authors.lastname: Taghavi
authors.affiliation: Department of Internal Medicine, Gastroenterology Ward, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Maryam
authors.initials: M
authors.lastname: Moeini
authors.affiliation: Department of Bacteriology and Virology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Behzad
authors.initials: B
authors.lastname: Dehghani
authors.affiliation: Department of Bacteriology and Virology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Maryam
authors.initials: M
authors.lastname: Sohrabi
mesh_terms: D000328:Adult; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D017291:Clarithromycin / Q000494:pharmacology*; D003430:Cross-Sectional Studies; D052978:Disk Diffusion Antimicrobial Tests; D024881:Drug Resistance, Bacterial; D005260:Female; D060005:Genotyping Techniques; D016481:Helicobacter Infections / Q000453:epidemiology / Q000382:microbiology*; D016480:Helicobacter pylori / Q000187:drug effects* / Q000302:isolation & purification; D006801:Humans; D007492:Iran / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D017354:Point Mutation; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D015995:Prevalence; D012338:RNA, Ribosomal, 23S / Q000235:genetics*; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents; D012338:RNA, Ribosomal, 23S; D017291:Clarithromycin
keywords: Clarithromycin resistance; Helicobacter pylori; Iran; Point mutation