BackgroundAdult food protein-induced enterocolitis syndrome (FPIES) has recently been recognized, and there are no international diagnostic criteria for this disease. Differentiating adult FPIES from immediate-type food allergy reactions and providing specific treatment for each in an emergency is important, but methods have not been developed. ObjectiveTo develop a diagnostic scoring system for adult FPIES by comparing it with an immediate-type food allergy (IgE-FA). MethodsThis retrospective cohort study of food-avoidant adults based on the diagnostic criteria for adult FPIES reported by Gonzalez et al. was conducted by telephone interviews. We compared the clinical profiles of the patients with FPIES and IgE-FA. Adult FPIES-associated factors were extracted using multivariate analysis, and a diagnostic scoring system was developed based on odds ratios (OR). ResultsForty-eight (16.7%) of 288 adults with food allergies were diagnosed with FPIES; of these, 240 (83.3%) had IgE-FA. Seafood was the most common cause of FPIES in adults (68.8%). Multivariate analysis identified age of onset > 26, >10 episodes, a longer latency period, cold sweat, abdominal distention, and vomiting as adult FPIES-associated factors. An adult FPIES diagnostic scoring system was developed using ORs with a high area under the curve (AUC = .978), 100% sensitivity and 87.0% specificity. ConclusionClinical profiles and an adult FPIES diagnostic scoring system were developed for the first time. This scoring system can be useful in differentiating adult FPIES and IgE-FA while treating a food-related acute reactions.