Food allergy and anaphylaxis – 2059. Mild symptoms induced by oral food challenge are not always associated with failed challenge results

Methods 4574 patients (average age 4.0 ± 2.6 years old, male-female ratio 1.89), who had received open-OFC to heated-egg or cow’s milk or wheat from 2005 to 2012, were enrolled to this study. Patients were divided into following 3 categories according to symptoms induced by OFC (primary diagnosis of FA). The “positive” group was patients who showed objective symptoms and “negative” group was patients who had not any symptoms. The third group was defined as “uncertain” who only showed subjective or weak objective symptoms such as slight erythema, mild abdominal pain or isolated cough. Patients with “negative” and “uncertain” group were asked to ingest causative foods or those products at home to confirm whether to induce any symptoms by the intake or not. In several weeks after OFC, we made the final diagnosis based on the information obtained from patients (final diagnosis of FA).