The Interleukin-8 -251 A Allele is Associated with Increased Risk of Different Gastroduodenal Diseases in H. pylori Infected Bangladeshi Patients

Abstract

Persistent Helicobacter pylori infection leads to chronic inflammation of the gastric mucosa which is mediated by various inflammatory cytokines. Host susceptibility along with bacterial virulence factors are also regarded as contributing factor of developing severe H. pylori induced gastroduodenal diseases like peptic ulcer diseases and gastric adenocarcinoma. Polymorphisms in genes that code cytokines influence cytokine secretion levels. Of the inflammatory cytokines, Interleukin-8 (IL-8) plays an important role in gastric mucosal inflammation induced by H. pylori infection. The IL8 gene has been described as having a polymorphism of an A/T base pair in the promoting region (−251) which is associated with an increased synthesis of interleukin by gastric epithelial cells. So the study was conducted to investigate the association of IL-8–251 A/T polymorphism with gastroduodenal diseases in H. pylori infected Bangladeshi patients. Methods: Endoscopic gastroduodenal biopsy sample of 113 dyspeptic patients were used (54 was infected with H. pylori and 59 was not infected with H. pylori). H. pylori infection was detected by Rapid urease test, PCR of ureC gene and histology. Gastroduodenal disease was diagnosed by histopathological examination. Il-8 gene polymorphism (at -251 position) was detected by Polymerase Chain Reaction restriction fragment length polymorphism. Result: A significant association was found between host IL-8 genotypes (T/T, T/A, A/A and A carrier) and the presence of H. pylori infection (p =0.001). The IL-8 A allele carriers infected with H. pylori had an increased risk of developing gastritis (p =0.003) and peptic ulcer diseases (p= .002). We did not find a correlation between IL-8 gene polymorphism and a higher risk of gastric carcinoma and or precancerous lesions. Conclusion: The H. pylori infected patients carrying A allele may increase risk of developing gastritis and peptic ulcer disease in Bangladeshi patients.