Insights into Pediatric Autoimmune Gastritis: Is There a Role for Helicobacter Pylori Infection?

Objectives: Autoimmune gastritis (AIG) is a chronic inflammatory condition of the gastric mucosa, mainly described in adults presenting with pernicious anemia. It results from antibody-mediated destruction of parietal cells, but the precise initiating event is unknown. The pathogenicity of Helicobacter pylori (H pylori) has been suggested but not established. This study aimed to better characterize AIG in pediatric patients and to address the possible role of H pylori infection. Methods: Descriptive single-center study, retrospectively describing 20 patients with a diagnosis of AIG based on positivity for anti-parietal cell autoantibodies, in addition to analytical and/or histological findings of oxyntic mucosa atrophy. Results: In the majority (18/20), AIG diagnosis was suggested during investigation of refractory iron-deficient anemia. One patient had dyspepsia and none of the others had gastrointestinal symptoms. Fifty-five percent (11/20) were H pylori positive, but there were no significant differences regarding mean hemoglobin values at presentation (10.6 +/- 2.5 vs 9.5 +/- 1.0 g/dL, P > 0.05), analytical indicators of gastric atrophy (gastrin, 564.4 +/- 184 vs 721.2 +/- 220.6 pg/mL, P > 0.05), or in the presence or the grade of oxyntic mucosa atrophy. Conclusions: Our findings highlight that AIG may have an age-dependent presentation; thus, we can consider a pediatric phenotype that in contrast to adults, is manifested by refractory iron-deficient anemia and associated with parietal cell autoantibody positivity, but not intrinsic factor autoantibodies. A correlation between H pylori and AIG was not evident in the current study and it is still unclear whether H pylori is a trigger for AIG.