Prevalence of Specific Helicobacter Pylori cagA, vacA, iceA, ureC Genotypes and its Clinical Relevance in the Patients with Acid-Peptic Diseases

Abstract

Introduction: Virulent markers of H. pylori, the vacuolating cytotoxin (vacA), cytotoxin-associated gene A (cagA), induced by contact with epithelium factor antigen (iceA gene) and the urease C gene (ureC) may plays a major role in determining the clinical outcome of Helicobacter infections. Aim: To detect the prevalence of the cagA, vacA, ureC and iceA genotypes of H. pylori from antral biopsy specimens of patients and to associate its role in specific disease. Materials and Methods: The study was conducted at Department of Microbiology of Shree P.M. Patel College of Paramedical Sciences, Anand, Gujarat, India. Seventy one antral biopsies of symptomatic patients referred for endoscopy from October 2012 to September 2013 were subjected to Multiplex PCR. DNA isolation from 71 biopsy samples was done by using “QIAamp DNA mini kit” from QIAGEN (GmbH, Hilden, Germany). Data was analysed using Chi square (χ2 ) test and p-value<0.05 was considered significant. Results: Out of the 71 biopsies screened, 22(31%) samples were positive for H. pylori by PCR, with high proportion of cagA positive (17/22 specimen; 77.27%), followed by ureC positive (4/22 specimen; 18.18%) and vacA positive (1/22 specimen; 4.54%) strains. Significant association was found between cagA and female gender (p-value=0.042). Out of 17 cagA positive strains, 9(52.94%) were found in patients with gastritis, 5(29.41%) in reflux oesophagitis and 3(17.64%) in patients with diodenal ulcer. We found 0% prevalence of iceA gene; conversely we had three peptic ulcer patients with only cagA positivity. Conclusion: The cagA positive strain mainly affects the patients with gastritis specifically of female gender and iceA genotype is not a useful marker associated with peptic ulcer disease. Patients should be screened for cagA genotype when reported to be a case of gastritis for early treatment to prevent further complications such as cancer.

Keywords

• cytotoxin associated gene a
• gastritis
• genotyping
• helicobacter pylori