Prevalence and Characteristics of Accidental Ingestions Among Pediatric Food Allergy Patients.

Background: Despite a known diagnosis of food allergy, accidental ingestions continue to occur.

Objective: To characterize accidental ingestions, including prevalence, risk factors, food allergen triggers, and severity of reactions.

Methods: A prospective monthly survey developed by the Food Allergy Consortium at Northwestern University was administered to parents of food-allergic children between April 2015 and April 2017. The monthly survey included questions on any allergic reactions experienced in the previous month. In addition, chart reviews of 100 pediatric participants from Lurie Children's Hospital of Chicago allergy clinics (typical clinical encounters) were compared with the prospective survey results.

Results: A total of 196 survey participants and 100 retrospective review subjects were analyzed-31.1% of participants from the surveyed cohort and 19.0% of participants from the retrospective review reported at least 1 accidental ingestion over 1 year. The rate of accidental ingestions reported in the prospective survey was high: 10% to 25% of participants each month reported an accidental ingestion, and multiple ingestions were common. Common triggers were milk, wheat, and tree nuts. In the retrospective cohort, the highest rate of accidental ingestion (25.0%) occurred for milk, followed by sesame (20.0%) and egg (18.8%). Rates of anaphylaxis after exposure were high in both the prospective and retrospective cohorts (33.1% and 16.7%, respectively).

Conclusions: Accidental ingestion rates were high among food-allergic patients. Multiple exposures, especially to milk, were common. Incidence of anaphylaxis was also high, suggesting that ongoing patient education on allergen avoidance and accidental exposure is imperative.