The use of skin prick tests and patch tests to identify causative foods in eosinophilic esophagitis

Background: Eosinophilic esophagitis is a disease entity in which patients have (1) elevated eosinophils on esophageal biopsy and (2) symptoms of gastroesophageal reflux. The symptoms do not improve on aggressive acid blockade but do improve on elimination diet or corticosteroid treatment, which tentatively links food allergies to this disorder. Objective: The purpose of this study was to identify potential food antigens in eosinophilic esophagitis. Methods: Patients with eosinophilic esophagitis were identified by biopsy. Potential food antigens were identified prospectively by skin prick testing and patch testing, which were performed through use of standard methods. Atopic tendencies, demo.. graphics, and potential food allergies were identified. Repeat esophageal biopsies were reviewed when possible. Results: A total of 26 patients (22 male, 4 female) with a biopsied-confirmed diagnosis of eosinophilic esophagitis underwent both skin prick testing and patch testing to identify potential causative foods. Milk and egg were the most common positive foods with skin prick testing. Wheat was the most common positive food with patch testing. The patients were advised to avoid positive foods as identified by skin prick testing and patch testing. In all, 18 patients had resolution of their symptoms, 6 patients had partial improvement, and 2 were lost to follow-up. Overall, after intervention, esophageal eosinophil counts improved from 55.8 to 8.4 eosinophils per high-power field. The foods most commonly identified by patients as causing symptoms were milk and egg. Conclusion: The combination of skin prick testing and patch testing can identify potential causative foods that might contribute to the pathogenesis of eosinophilic esophagitis.