000854 - Allergen and Panallergen Sensitization Profile in Pediatric Eosinophilic Esophagitis Patients: a single centre experience

Eosinophilic esophagitis (EoE) is a chronic, immune-mediated disorder associated with atopic comorbidities and considered a potential late manifestation of the atopic march. This study aims to evaluate the prevalence of sensitization to foods, aeroallergens, and panallergens in pediatric EoE patients, and to examinepatients clinical characteristics and response to induction therapy with proton pump inhibitors (PPIs).

A prospective, cross-sectional study was conducted at Buzzi Children’s Hospital, Milan, including pediatric EoE patients diagnosed since January 2016. All patients received 8 weeks of high-dose PPI therapy. Data on family history, allergic comorbidities, and sensitization to allergens and panallergens were collected. Clinical, endoscopic, and histological data were assessed at diagnosis and follow-up. Statistical analyses were performed using Fisher’s exact test and t-tests.

24 patients (mean age 10.9 years; 23 males) were enrolled. 79% (19/24) had a family history of atopy and presented allergic comorbidities, including allergic rhinitis (50%, 12/24), atopic dermatitis (42%, 10/24), asthma (33%, 8/24), and food allergies (25%, 6/24). Total IgEs were elevated in 79% (19/24). Polysensitization to food allergens (≥3 allergens) was common (71%, 17/24), notably to wheat (79%, 19/24), tree nuts (67%, 16/24), and sesame (63%, 15/24). Inhalant sensitization was observed in 70% (14/20), mainly to grass pollen (75%, 15/20) and Betulaceae (65%, 13/20). Panallergen sensitization was present in 64% of the cohort (15/24), with Bet v1 and Phl p12 being the most frequent (42% each, 10/24). Histological remission following PPI therapy was achieved in 25% (6/24). PPI non-responders after induction therapy (75%, 18/24) showed significantly higher rates of panallergen sensitization (78%, 14/18 vs. 17%, 1/6; p=0.015) and a higher prevalence of atopic dermatitis (56%, 10/18 vs. 17%, 1/6; p<0.05).

This study highlights, for the first time, the role of panallergens sensitization in pediatric EoE and its possible involvement in predicting PPI response. The presence of atopic comorbidities and patients’ sensitization profile should be taken into account in treatment decision making. Further research is needed to confirm these findings.