Detection of vacA and cagA genes in Helicobacter pylori strains in Salvadoran patients

Abstract

Introduction. Helicobacter pylori infection has become an prevalent disease and an economic and public health problem. The main concern is that some strains are associated with gastric cancer, especially the vacA and cagA genes. Objective. Determine the prevalent Helicobacter pylori genotypes in patients who attended the Specialty Clinic of the Salvadoran Social Security Institute. Methodology. A quantitative, descriptive, cross-sectional study was conducted. The unit of analysis was endoscopic
gastric samples. A consecutive non-probabilistic sampling was performed. The selection of patients was carried out by a gastroenterologist. The real-time polymerase chain reaction technique was applied to identify the virulence genes, cagA and vacA of cultures positive for Helicobacter pylori, using standardized methods. Results. Ninety-seven participants were obtained, from whom a biopsy sample was acquired and cultured; however, the recovery rate of Helicobacter pylori in culture was 26 %. All samples were positive for the 16S rRNA ribosomal virulence genes and the cagA and vacA oncogenes. The infection was predominant in females, with 76 %, and the average age was 55 years. It was found that 64 % of positive participants had a previous diagnosis of infection with Helicobacter pylori. Conclusion. The virulence genes cagA and vacA were found in all samples positive for Helicobacter pylori.