Esophagus to Small Intestine
Am J Gastroenterol. 2024;119(5):837–45
Long-term natural history of autoimmune gastritis: Results from a prospective monocentric series
Introduction: The natural history of autoimmune gastritis (AIG) has been poorly described. In this study, the authors report the long-term natural history and clinical clustering of the full spectrum of AIG, from the potential to the complicated stage.
Methods: Prospective single-center study conducted in a tertiary referral center. Patients with AIG at any stage (0 = potential; 1 = early; 2 = florid; 3 = severe; and 4 = complicated) were enrolled (January 2000 to December 2022). The histopathological evolution, the clinical presentation, and the correlates of evolution of potential AIG were assessed.
Results: 498 patients with AIG (mean age, 56.7 ± 15.2 years, female:male ratio 2.5:1) were included, of whom 93 experienced potential AIG. The maximum disease duration was 27 years (median, 18 years, interquartile range [IQR], 14–23), while the overall median follow-up was 52 months (IQR, 12–95). Age was significantly lower in stage 0 compared with that in the other stages. Accidental histologic evidence and hematologic findings were the most common clusters of diagnosis. The overall median rate of progression was 7.29 per 100 persons/year (95% confidence interval [CI]: 6.19–8.59), while the stage-specific rates of progression were 10.85 (stage 0; 95% CI: 7.75–15.18), 14.83 (stages 1–2; 95% CI: 11.89–18.49), and 2.68 (stage 3; 95% CI: 1.88–3.84). Newly onset neoplastic complications at follow-up occurred in 41 of 483 patients (8.5%; 23 neuroendocrine tumors and 18 epithelial dysplasia). No cases of adenocarcinoma were noticed. Male sex was associated with a greater likelihood of evolving from potential AIG to overt AIG.
Discussion: Autoimmune gastritis (AIG) is a progressive disorder, with a virtually absent risk of gastric adenocarcinoma. Patients with potential AIG should be monitored because they carry a high risk of evolving into overt AIG.