Alpha defensin expression in gastric tissue in childhood helicobacter pylori infection

SUMMARYα-defensin expression in gastric tissue in childhood Helicobacter pyloriinfectionDr. Özlem Bekem SoyluAim: We aimed to investigate the expression of α-defensin, a natural antibiotic, ingastric mucosa and the relation of its expression with histopathological findings likebacterial density, chronic inflammation and neutrophil infiltration in Helicobacter pylori(H. pylori) infection, which is a leading cause of chronic gastritis in childhood.Materials and methods: From children with dyspepsia, to whom uppergastrointestinal endoscopy was performed to search for the etiology, 20 withdemonstrated H. pylori infection and 25 H. pylori negative children with similar ageand sex ratio were included in the study as the study and the control grouprespectively. Hospital records were examined and presenting symptoms,anthropometrical measurements, hemoglobin levels, endoscopic andhistopathological findings were noted. Endoscopic and histopathological findingswere evaluated according to the Sydney System. Immunhistochemical staining wasperformed in order to demonstrate α-defensin expression in gastric mucosa. H. pyloripositive and negative, α-defensin positive and negative groups were compared withregard to these variables.Results: The most common presenting symptom was abdominal pain. H. pyloripositive and negative groups were not different in malnutrition or anemia rate. Themost common endoscopic diagnosis was erythematous/exudative gastritis. Antralnodularity was defined almost only in H. pylori positive group. Chronic inflammation,neutrophil and α-defensin density was significantly higher in H. pylori positive group,while intestinal metaplasia or glandular atrophy was not found in any of the patients.A positive relation was found between H. pylori density and neutrophil infiltration.Neutrophil infiltration and chronic inflammation score was higher in α-defensinpositive cases.Conclusion: Similar to adults, α-defensin expression increases in H. pylori infectionin childhood. It is concerned that innate immune answer seen in response to H. pyloriinfection in childhood gastrointestinal system is not different from adults, at least forα-defensins. This finding indicates that the more frequent and easy occurrence of thisinfection in children compared to adults could not be explained by the tissue α-defensin expression status.Key words: Children, defensin, gastritis, Helicobacter pylori, inflammation, innateimmune system