Phenotypes and natural history of food protein-induced enterocolitis syndrome in the east Mediterranean region.

Background: Food protein-induced enterocolitis syndrome (FPIES) is a rare non-IgE mediated food allergy. Objective: To delineate the differences in the spectrum of culprit foods, remission patterns, and predictors among varying cultures. Methods: We reviewed demographics, culprit foods, outcomes, and predictors in 81 children with a diagnosis of FPIES who were followed up between 2015 and 2020. Results: Eighty-one patients (55.6% boys) were enrolled, including 72 with acute FPIES and 9 with chronic FPIES. Hen's egg was the most common culprit food (36.6%), followed by fish (26.9%), and cow's milk (21.5%). Interestingly, cow's milk was significantly prevalent in chronic FPIES cases (p = 0.006). The most common clinical symptoms were vomiting (100%), pallor (63.4%), and lethargy (55.9%). Emergency department visits were noted in 39 patients (41.9%), of whom 37 (39.8%) were treated with intravenous (IV) fluid. The subjects were followed up for a median (interquartile range) of 19.4 months (12.3-41.2 months), and 26 subjects (32.1%) achieved tolerance. The median (interquartile range) age at tolerance was 2.5 years (2.1-3.2 years). With regard to the culprit foods, hen's egg was observed more frequently in the subjects with resolved FPIES cases (p = 0.008), whereas fish FPIES cases were high in the persistent group (p = 0.001). IgE sensitization of the culprit food was found to be an independent risk factor for the persistence of FPIES (odds ratio 4.855 [95% confidence interval, 1.131-20.844]; p = 0.034). Conclusion: In our cohort, unlike other published series, hen's egg and fish were the two most common culprit foods. Fish differed from other culprit foods, with significantly delayed onset and persistence, and may create a model that allows for the understanding of the disease.