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.