title: Evaluation of Helicobacter pylori vacA and cagA Genotypes and Correlation With Clinical Outcome in Patients With Dyspepsia in Hamadan Province, Iran.
abstract: BACKGROUND
  Helicobacter pylori is known to be a causative agent of chronic active gastritis, peptic ulcer and gastric cancer in human. Diverse genotypes of H. pylori strains have different virulence potency and geographic distribution.
  
  
  OBJECTIVE
  The purpose of this study was to investigate the association between the cytotoxin-associated gene (cagA), and the various vacuolating cytotoxin (vacA) genotypes of H. pylori strains and clinical outcomes in patients referred to Shahid-Beheshti Hospital in Hamadan, Iran.
  
  
  METHODS
  In this cross-sectional study, biopsy samples were collected consecutively from 153 patients with gastric cancer (GC), peptic ulcer dyspepsia (PUD) and non-ulcer dyspepsia (NUD) in the gastroenterology department of Shahid-Beheshti Hospital in Hamadan province, the west of Iran. H. pylori infection was confirmed in 83 patients (3 with GC, 27 with PUD, and 53 with NUD) by histology, rapid urease test (RUT) and culture. Genomic DNA was extracted from the bacterial isolate and was further confirmed with 16S rRNA gene sequencing as H. pylori, and characterized based on cagA and vacA genotyping using the polymerase chain reaction (PCR) method.
  
  
  RESULTS
  In this study, vacA genotypes s1/m2, s1/m1, s2/m2 and s2/m1 were determined in 43.4%, 19.3%, 13.2% and 6% of the isolated H. pylori, respectively. The vacAs1 genotype was detected in 52 (62.6%) isolates, of which the vacAs1a genotype was detected in 45.2, 40.7, and 66.6% of the isolates from patients with NUD, PUD, and GC, respectively. The cagA-positive genotype was determined in 73 (87.9%) isolates and 10 (12.1%) were negative. The frequency rates of cagA gene were 84.9, 92.6 and 100% in isolates of patients with NUD, PUD, and GC, respectively. The cagA-positive genotype is strongly associated with s1a/m2 and s1a/m1 vacA genotypes.
  
  
  CONCLUSIONS
  The most predominant VacA genotypes in our areas were s1/m2 and s1/m1, which regard as the genotypes with more virulence intensity. The H. pylori vacAs1a, cagA genotypes have a significant relationship with the presence of PUD and GC in Iranian patients with dyspepsia.
authors.affiliation: Brucellosis Research Center, Hamadan University of Medical Sceinces, Hamadan, IR Iran ; Department of Microbiology, Faculty of Medicine, Hamadan University of Medical Sciences, Hamadan, IR Iran.
authors.forename: Mohammad Yousef
authors.initials: MY
authors.lastname: Alikhani
authors.affiliation: Brucellosis Research Center, Hamadan University of Medical Sceinces, Hamadan, IR Iran ; Department of Microbiology, Faculty of Medicine, Hamadan University of Medical Sciences, Hamadan, IR Iran.
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Arebestani
authors.affiliation: Department of Microbiology, Faculty of Medicine, Hamadan University of Medical Sciences, Hamadan, IR Iran.
authors.forename: Masood
authors.initials: M
authors.lastname: Sayedin Khorasani
authors.affiliation: Department of Gastrointestinal Diseases, Beheshti Hospital, Hamadan University of Medical Sciences, Hamadan, IR Iran.
authors.forename: Amir
authors.initials: A
authors.lastname: Majlesi
authors.affiliation: Department of Pathology, Faculty of Medicine, Hamadan University of Medical Sciences, Hamadan, IR Iran.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Jaefari
keywords: Genotyping; Helicobacter Pylori; VacA; cagA