Evolution of Food Protein-Induced Enterocolitis Syndrome (FPIES) Index Trigger Foods and Subsequent Reactions After Initial Diagnosis

BACKGROUND: Food protein-induced enterocolitis syn-drome (FPIES) is a non-IgE-mediated food allergy treated by trigger food avoidance and supportive care. Whether the prev-alence of different trigger foods is changing with evolving food introduction patterns is unknown. The rate and nature of sub-sequent reactions after initial diagnosis have not been fully studied. OBJECTIVE: We sought to characterize how trigger foods have changed over time and investigate the nature of subsequent reactions after initial diagnosis. METHODS: We collected data regarding patients' FPIES reactions from 347 patients seen in the University of Michigan Allergy and Immunology clinic for FPIES from 2010 to 2022. Inclusion criteria consisted of pediatric patients diagnosed with FPIES by an allergist based on international consensus guidelines. RESULTS: Most foods including less commonly cited FPIES triggers increased in frequency over time. The most common index trigger was oat. A total of 32.9% (114 of 347) patients experienced a subsequent reaction after education on trigger avoidance and safe home introduction of new foods, with 34.2% (41 of 120) of subsequent reactions to new triggers at home and 45% (54 of 120) to known triggers at home. Of patients reacting subsequently, 28% (32 of 114) experienced a subsequent reaction necessitating an emergency department visit. The most common new subsequent reaction triggers were egg and potato, whereas peanut most commonly triggered reactions on oral food challenge. CONCLUSIONS: The risk profile of FPIES triggers may be evolving over time, though high-risk FPIES foods remain com -mon. The subsequent reaction rate after counseling indicates that home food introduction poses risk. This study highlights the need for improved safety of new food introduction and/or prediction methods for FPIES to help prevent potentially dangerous home FPIES reactions. (c) 2023 American Academy of Allergy, Asthma & Immunology (J Allergy Clin Immunol Pract 2023;11:3179-86)

Automated summary

The prevalence of trigger foods in food protein-induced enterocolitis syndrome (FPIES) may be changing over time, with most foods, including less commonly cited triggers, increasing in frequency. The most common initial trigger is oat. Subsequent reactions after education on trigger avoidance and safe home introduction of new foods were observed in 32.9% of patients, with 41% being reactions to new triggers and 45% to known triggers. Among those who reacted subsequently, 28% required emergency department visits. Egg and potato were the most common new triggers, while peanut commonly triggered reactions on oral food challenge.