Analysis of pathological diagnostic characteristics of non-esophageal eosinophilic gastrointestinal disorders

To investigate the pathological diagnostic features of non-esophageal eosinophilic gastrointestinal disorders (non-EoE EGIDs) and establish site-specific pathological diagnostic workflows. A retrospective case-control study was conducted on 444 biopsy specimens from 70 non-EoE EGIDs patients (2012-2023, Peking Union Medical College Hospital). Controls groups included 200 specimens from 155 chronic active gastroenteritis patients and 282 specimens from 134 patients with Crohn's disease, Behçet's disease and chronic active colitis of unexplained etiology. Pathological features were compared using chi-square tests, Bonferroni post-hoc tests, and modified Poisson regression analyses. The features assessed included eosinophil counts, infiltration sites, villous blunting, intraepithelial neutrophil infiltration/cryptitis, lamina propria neutrophilic infiltration, edema, and the degree of lymphoplasmacytic infiltration. In the stomach, no significant differences were observed in any pathological features between non-EoE EGIDs and controls. In the duodenum, small bowel, and colon, significant differences were observed in eosinophil counts, infiltration sites, and the other morphological indicators. Multivariable modified Poisson regression identified independent pathological predictors in these three segments. High-density eosinophil patterns and intraepithelial eosinophil infiltration are key diagnostic features of non-EoE EGIDs. Other morphological indicators serve as important auxiliary diagnostic criteria.