Mucosal Atrophy of the Fornix as an Important Endoscopic Finding for an Autoimmune Gastritis Diagnosis.

Objective This study investigated the significance of diagnosing an endoscopic atrophic pattern of the fornix in autoimmune gastritis (AIG). Materials Of 10,608 individuals (men/women: 6,551/4,057) who underwent an esophagogastroduodenal endoscopy (EGD) examination between April 2016 and March 2022 for a medical checkup, 80 patients (men/women: 34/46, mean age 58.7 years old) were diagnosed with AIG based on endoscopic findings and positivity for gastric autoantibodies. The mucosal atrophy pattern of the fornix shown in the endoscopic findings of AIG cases was divided into four classifications: none, patchy, wide-range, and whole. Results The number of AIG cases classified as none, patchy, wide-range, and whole was 9, 26, 14, and 31, respectively. Whole-fornix atrophy was frequently observed in Helicobacter pylori-uninfected cases, while the atrophic pattern was correlated with the area of remnant oxyntic mucosa in the gastric body. The serum levels of pepsinogen I and pepsinogen I/II ratio decreased, while the gastrin level increased in association with the enlarged atrophic area of the fornix. The pepsinogen I/II ratio was ≥3.0, in 70.8% of the cases, with a patchy pattern. Follow-up EGD findings obtained after the AIG diagnosis showed gradual progression of mucosal atrophy of the fornix, with such progression primarily observed in H. pylori-eradicated cases. Conclusion The degree of endoscopic atrophy of the fornix was correlated with AIG progression. Patchy atrophy pattern in the fornix may be helpful in the detection of AIG prior to oxyntic gland atrophy expansion.