Distribution of esophageal inflammation in patients with eosinophilic esophagitis and its impact on diagnosis and outcome

Background: This study aimed to assess the distribution of esophageal inflammation in patients with eosinophilic esophagitis (EoE) and its impact on diagnosis and outcome. Aims and Methods: Data from consecutive adult EoE patients who were followed-up at four Italian referral centers from October 2022 to October 2023 were retrospectively collected. Results: One hundred forty-nine patients were included. Proximal EoE was observed in 8.1 % of patients; distal EoE in 27.5 %; and diffuse EoE in 64.4 %. Allergic rhinitis was more prevalent in distal and diffuse than proximal EoE (72.5 % vs. 61.5 % vs 33.3 %; P = 0.049). The prevalence of asthma, atopic dermatitis, oral allergy syndrome, and gastroesophageal reflux disease was not significantly different among the three EoE extent groups. Endoscopic inflammatory features at diagnosis were more prevalent in proximal EoE (91.7 % vs. 53.8 % distal [P = 0.01] vs. 66 % diffuse[P = 0.05]). No significant differences in fibrotic features and esophageal stenoses were observed. The clinical and histological remission rates after first-line therapy were comparable in all groups. Conclusion: Esophageal inflammation in EoE more frequently involves the entire esophagus, followed by isolated distal and proximal involvement. No clear correlation was observed between the histological extent of EoE at diagnosis and comorbidities or treatment response.