Food protein–induced enterocolitis syndrome is an important differential diagnosis of vomiting in pediatric emergency.

Background: The aim of this study was to clarify the clinical characteristics and management of infants with suspected acute food protein–induced enterocolitis syndrome (FPIES) who presented to the pediatric emergency department (ED) before and after the guidelines were published. Methods: This was a retrospective cohort study. We classified the infants as "acute FPIES‐like symptoms" who were younger than 12 months of age and visited the pediatric ED of the National Center for Child Health and Development due to vomiting 1–4 h after food ingestion without any causative disease, such as infection. The medical records of those infants in 2015 and 2021 were reviewed. We used the nonparametric Mann–Whitney U test to compare two groups for continuous variables, whereas chi‐squared or Fisher's exact tests were used for nominal variables. Results: The number of infants with acute FPIES‐like symptoms was 15 (13%) in 2015 and 14 (15%) in 2021. The trigger foods were cow's milk or dairy products in half of the infants, and five as a result of ingestion of hen's eggs in 2021, compared to zero cases in 2015. Five in 2015 and 12 in 2021 required examination at the ED. Three in 2015 and six in 2021 met the diagnostic criteria for acute FPIES in the international consensus guidelines. The emergency physicians did not record at least four minor criteria for acute FPIES in seven in 2015 and five in 2021. No infants (0%) in 2015 and two (14%) in 2021 were referred to the allergy department by an emergency physician. Conclusions: Acute FPIES should be considered one of the differential diagnoses of vomiting, and pediatric medical staff should be aware of FPIES diagnostic criteria and appropriately refer suspected cases to a specialist. [ABSTRACT FROM AUTHOR]