Studying the Prevalence of <i>Helicobacter pylori</i> Genotypes <i>vacA</i>, <i>cagA</i>, <i>babA</i>, <i>sabA</i>, and <i>oipA</i> in Patients with Gastrointestinal Problems

Abstract

Background: Although Helicobacter pylori is a well-known pathogen of gastrointestinal diseases, the regional differences in its virulence gene profiles have not yet been sufficiently investigated. Given the high prevalence of H. pylori in gastrointestinal diseases and the relationship between the virulence factors of this bacterium and the importance of its virulence genes in causing various diseases, it is of great importance to study the prevalence and determine the frequency of the pathogenic genes of this bacterium in each geographical region of the country. Objectives: The aim of this study was to characterize the distribution of major virulence genes in H. pylori strains isolated from patients referred to an Iranian hospital and to assess the potential impact on disease severity and public health. Methods: A total of 79 gastric biopsy samples were collected over three months. Of these, 32 H. pylori isolates were confirmed by phenotypic and polymerase chain reaction (PCR)-based genotypic methods. The presence of five virulence genes [vacA, cagA, babA, sialic acid-binding factor (sabA), and oipA] was investigated by PCR. Results: The most prevalent virulence gene was sabA (81.2%), followed by oipA (71.8%), babA (59.3%), and cagA (50%). Analysis of the vacA genotypes revealed that s1m2 was the most common variant (46.8%), followed by s2m2 (28.1%), s1m1 (21.8%), and s2m1 (3%). The detection of the highly virulent vacA s1m1 genotype in almost a quarter of the isolates indicates a considerable presence of strains with increased pathogenic potential. Conclusions: This study shows a high prevalence of virulence-associated genes among the H. pylori strains in the study population, in particular sabA, oipA, and the vacA genotypes s1m2 and s1m1. These results emphasize the need for routine genotypic screening of H. pylori in the clinical setting to better predict disease progression and determine treatment strategies, which would ultimately contribute to better treatment of gastrointestinal infections in Iran.