Determination of Helicobacter pylori Virulence Genes in Clinical Isolates of Symptomatic Patients from South Coastal Region of Karnataka - A Preliminary Work

Introduction: Helicobacter pylori is a microaerophilic, spiral shaped, unipolar flagellated, gram negative organism which has high tropism towards gastric epithelial cells and may lead to a severe form of gastroduodenal disease. Prevalence of H pylori infections in developing countries may exceed 70% but only a fraction of people develop severe disease. The involvement of H. pylori virulence factors cagA and vacA genotypes are well studied and show high genetic diversity geographically. The present study was conducted to detect the Presence of H. pylori in biopsy samples from symptomatic patients by Rapid Urease Test, histopathological examination and Culture .It also involved the detection of virulence genes cagA, vacA (s1m1, s1m2 and s2m2) genotypes from the isolated strains. Materials and Methods: Patients with complaints of abdominal pain, discomfort, acidity and loss of appetite were chosen for endoscopy. A detailed history was taken and physical examination of the patients was carried out prior to endoscopy. A total of 3 antral biopsies were obtained from each patient and subjected to RUT, HPE and culture. Isolated H. pylori were further examined for the virulence genes by using PCR. Results: Antral biopsies were collected from a total of 38 patients. Identification of H. pylori was performed on all gastric biopsies by RUT, HPE and Culture. The rate of positive H. pylori in the biopsies tested with RUT were (36.9%), HPE (42.1%) and Culture (39.5%) and the presence of virulence gene cagA (93.3%) and vacA alleles- s1m1 (60%), s1m2 (40%). None of them showed presence of vacA s2m2 genotypes by PCR. Conclusion: This study provides important information regarding the rate of identification of Helicobacter pylori from RUT, HPE, Culture and also rate of virulence genes harbored by strains isolated from this part of Karnataka., India.