Prevalence of EPIYA motifs in Helicobacter pylori strains isolated from patients with gastroduodenal disorders in northern Iran

Background: Cytotoxin-associated gene A (CagA)-positive strains of Helicobacter pylori are associated with gastroduodenal diseases. Evidences have suggested that the type of H pylori CagA EPIYA motifs may be associated with specific disorders (i.e., gastritis, peptic ulcer, or gastric cancer).  We investigated the prevalence of different EPIYA motifs (A, B, C, or D) in H. pylori strains isolated from patients with recurrent dyspepsia who underwent upper gastrointestinal (GI) endoscopy. Materials and Methods: H. pylori strains were isolated from biopsy specimens of ۲۲۰ patients with dyspepsia symptoms. The presence of glmM gene, as a housekeeping gene CagA and pattern of cagA EPIYA motifs were genotyped using by polymerase chain reaction (PCR) method.The association between the type of motifs and disease state determined by the Chi-square test, Fisher’s exact test, and logistic regression. Results: CagA-positive H. pylori were identified in ۱۲۵(۵۷%) of patients with gastrointestinal disorders, of whom ۳۶(۲۸.۶%) were isolated from gastritis, ۳۱ (۲۴.۶%) from duodenal ulcer, and ۵۸ (۴۶.۴%) from gastric cancer. The frequency of pattern of cagA EPIYA motifs were ۳۹ (۳۱.۲%) AB motifs, ۵۴ (۴۳.۲%) ABC motifs, and ۳۲ (۲۵.۶%) ABCC motifs and not detected D motifs. Gastric cancer risk was estimated to be ۲.۵۷ times higher in patients infected by strains with ABCC motif when compared with gastritis and duodenal ulcer patients (P=۰.۰۳). Moreover, patients with C- containing motifs were ۲.۲۷ times more likely to be affilicted with gastric cancer than duodenal ulcer. AB motif was more associated with gastritis and duodenal ulcer than ABC and ABCC motifs. Conclusion: The results suggested that cag-EPIYA ABCC might be associated with gastric cancer, while EPIYA-AB might be is associated with duodenal ulcer.

Keywords:

Helicobacter pylori , Cytotoxin-associated gene A , gastritis , peptic ulcer , Iran