Severity Trend of Recurrence in Pediatric Food Protein-Induced Enterocolitis Syndrome.

Background: Reintroduction of the offending food in pediatric patients affected by food protein-induced enterocolitis syndrome (FPIES) is carried out in hospitals with an oral food challenge (OFC), which leads to a long waiting time and increases the societal burden of medical cost and human resources.

Objective: To assess the severity trend of acute FPIES adverse reactions over time in the same patient for possible outpatient or home reintroduction of the offending food.

Methods: All children (aged <18 years) with a diagnosis of acute FPIES referred to two Italian pediatric allergy clinics were retrospectively enrolled. To determine whether home or outpatient clinic reintroduction of trigger food was possible, a risk of severe reactions of 5% or less was arbitrarily considered acceptable.

Results: Of202 patients enrolled, 23 (11.4%) had increasing severity from mild to moderate up to severe episodes. No variables analyzed in these patients (sex, age at onset, and the interval between the first and severe episodes) had a statistically significant influence on the risk of more severe reactions. Of all patients who initially presented with mild or moderate episodes, 15.2% and 13.9% later manifested severe episodes over time, respectively. Of patients with cow's milk FPIES that started with a mild episode, 5.5% later experienced a severe episode.

Conclusions: Performing OFC for acute FPIES is not safe enough at home because the probability of severe adverse reaction is greater than 5%. However, it could be considered to perform OFC in an outpatient clinic in patients with cow's milk FPIES who started with a mild episode and if a rapid transfer plan to emergency department is available.