D2.118 - Eosinophilic Esophagitis and Atopy: A Shared Mechanism of Type 2 Inflammation

Eosinophilic Esophagitis (EoE) is a chronic inflammatory disease characterized by severe and localized eosinophilic infiltration of the esophagus. EoE patients frequently exhibit atopic conditions, including allergic rhinitis (AR) and allergic asthma (AA). However, the role of atopy in EoE is not yet well defined. The aim of our study was to identify potential respiratory allergic diseases in EoE patients and to characterize their sensitization profile to aeroallergens.

Twenty-four patients with EoE were consecutively recruited in the Allergy Unit, and demographic and clinical data were collected. Those with clinical symptoms suggestive of AR and/or AA underwent allergy work-up, including skin prick tests for common aeroallergens, followed by in-vitro tests for detection of specific IgE. The sensitization profiles to different aeroallergens were evaluated using ImmunoCAP technology. In patients with AA, the severity of the disease was classified according to Global Initiative for Asthma (GINA) recommendations.

In our study, 24 patients (13 males, 11 females) with a mean age of 35.3 years (range: 19-72) were recruited. Among them, 87.5% were atopic, with a diagnosis of AR in 71%, AR+AA in 46%, and none with only AA. Asthma was classified based on GINA guidelines: 5 out of 11 were classified as step 1-2, and none were classified as step 3-4 or 5. Among them, 73% had early-onset asthma, while 27% had late-onset asthma. According to the allergy work-up, the most common aeroallergen in the atopic patients was grass pollen (88%), followed by cypress (65%), birch (65%), parietaria (59%), and olive tree (59%). Among the perennial allergens, the most frequent allergen was Dermatophagoides Pteronissinus (58.3%), followed by Dermatophagoides Farinae (29.2%), cat dander (47%), and dog dander (29%).

Most EoE patients were atopic, with a prevalence of respiratory allergic diseases, including AR and AA. Our data strongly suggest that EoE is part of the spectrum of allergic disorders driven by type 2 inflammation. This shared mechanism is further highlighted by the efficacy of the recently approved biological therapy in EoE with anti-IL-4/IL-13 monoclonal antibodies. Therefore, a systematic diagnostic allergy work-up, including both in-vivo and in-vitro tools, is required to better endotype atopic EoE patients and consequently plan the most suitable therapeutic approach, in light of the new biological therapies.