Innate immunity – the hallmark of Helicobacter pylori infection in pediatric chronic gastritis

BACKGROUND: Innate immunity was found to be associated with both persistence of Helicobacter pylori (H. pylori) infection and increased risk of gastric cancer. AIM: To identify the risk factors associated with H. pylori infection and to establish the role of TLR9 rs352140 in suppressing or promoting inflammation related to this infection in children. METHODS: We performed a study of 155 children with digestive symptoms, who were divided into two groups according to the histopathological exam: Group 1 – 48 children with H. pylori-induced chronic gastritis, and Group 2 – control group. RESULTS: Rural area and poor living conditions were significantly associated with H. pylori chronic gastritis (P = 0.0042/P < 0.0001). Both positive immunoglobulin A anti H. pylori and the rapid urease test were significantly associated with H. pylori infection (P < 0.0001). Significantly higher values of leukocytes and neutrophils within the peripheral blood were found in children with H. pylori chronic gastritis (P = 0.111/P = 0.284). We found a significant positive correlation between the variant TT genotype of TLR9 rs352140 polymorphism and both leucocytes and neutrophils (P = 0.0225/P = 0.0292). CONCLUSION: Variant TT genotype carriers of the TLR9 rs352140 gene polymorphism might have a more severe degree of inflammation.