Association Between Selected Human Leukocyte Antigen Alleles and Helicobacter pylori Infection Among Dyspeptic Patients

Abstract

Background: Helicobacter pylori has been identified as a group I carcinogenic bacterium that infects the gastric mucosa leading to gastritis, peptic ulcer disease, lymphoma, and gastric cancer. Pathogenesis of H. pylori depends on the virulence of the strain, host immune response, and modulating factors like smoking and diet. Objectives: This study aimed to assess the association between selected human leukocyte antigen (HLA) alleles including HLA-DQA1*0102, HLA-DQA1*0103, and HLADQB1*0301, and the presence of H. pylori infection and disease severity among dyspeptic patients. Materials and Methods: Gastric tissue samples were collected from 100 dyspeptic patients, who underwent upper gastrointestinal endoscopy at a tertiary care hospital. Presence of HLA alleles was confirmed using polymerase chain reaction (PCR). Helicobacter pylori infection was determined using PCR and Histology. The histological interpretation was done according to the ‘Sydney classification.’ Statistical analysis was done with SPSS version 22. Results: Respective percentages of HLA-DQA1*0102, HLA-DQA1*0103, and HLADQB1*0301 were 39%, 31%, and 20%, respectively. Of the 25 samples positive for H. pylori infection, 56% (14/25), 36% (9/25), and 12% (3/25) were positive for HLA-DQA1*0102, HLA-DQA1*0103, and HLA-DQB1*0301 alleles respectively. Considering the association with H. pylori infection, only HLA-DQA1*0102 showed significant association (P = .044). No significant association was found between the HLA alleles and the histological severity among the H. pylori infected patients. Conclusion: Investigation of immunogenetic factors contributing to susceptibility or resistance to H. pylori infection in Sri Lanka can provide an insight into understanding the risk of developing severe pathological complications among patients.