The Role of Allergy Testing in Treatment Selection of Pediatric Eosinophilic Esophagitis

Introduction: Eosinophilic Esophagitis (EoE) is a chronic and recurrent disease characterized by symptoms associated with esophageal dysfunction and histopathologically by eosinophil-predominant inflammation. Our study aims to evaluate the role of diagnostic allergy tests in the selection of food elimination diets in EoE using real-world data and to compare the efficacy of medical treatment alone versus medical treatment with dietary intervention. Methods: This retrospective cohort study included 53 patients with complete data who were followed with a diagnosis of EoE at the Pediatric Allergy and Immunology Clinic between October 2022 and December 2025. All patients were evaluated with food and aeroallergen skin prick tests (SPT) and specific IgE (sIgE) measurement, and with atopy patch testing where indicated. Treatment response was assessed by combined clinical, endoscopic and histological evaluation 12 weeks after the start of treatment. Predictors of response were examined by univariable analysis and by multivariable binary logistic regression. Results: Thirty-three of the 53 patients (62.3%) responded to treatment. Medical treatment alone was administered to 52.8% of the cases, while 47.2% received dietary therapy in addition to medical treatment. Response was achieved in 47.4% of patients treated with a proton pump inhibitor (PPI) alone and in 70.6% of those who received a topical steroid and/or an elimination diet in addition to a PPI (p=0.140). Among the patients treated with an elimination diet, the response rate was 76.9% when at least one trigger food had been identified by an allergy test and 50.0% when all allergy tests were negative and the diet was empiric (p=0.226). Treatment response was significantly less frequent in patients sensitized to aeroallergens (42.1% vs. 73.5%; p=0.038). In multivariable logistic regression, aeroallergen sIgE positivity was independently associated with a lower probability of response (adjusted odds ratio [aOR] 0.12, 95% confidence interval [CI] 0.02-0.58; p=0.008) and food sIgE positivity with a higher probability of response (aOR 7.07, 95% CI 1.20-41.64; p=0.031). Symptoms began earlier in children with a past history of food allergy (p=0.004). Conclusion: In this cohort, allergy testing didn’t identify a subgroup in which a test-directed elimination diet outperformed an empiric one, which supports current guideline recommendations to start elimination empirically. The aeroallergen sensitization was independently associated with a lower likelihood of treatment response. Treatment success in eosinophilic esophagitis may therefore be optimized through personalized approaches that consider the whole allergic phenotype of the patient rather than food test results alone.