Low-dose oral food challenges

Abstract

Background: Infants aged <1 year with confirmed food allergies generally need to avoid causative foods completely for a certain period. Low-dose oral food challenges (LD-OFCs) may be an effective strategy for safely introducing small amounts of causative foods to individuals with food allergies. This study clarified the safety of LD-OFCs in infants aged <1 year with food allergies.

Methods: We retrospectively analyzed the clinical records of LD-OFCs performed in infants aged <1 year allergic to hen's egg, cow's milk, or wheat between April 2014 and October 2017. Approximately 1/25th-1/20th of the egg white from a heated whole hen's egg, 3 mL heated cow's milk, and 2 g wheat noodles (udon) were used as challenge foods. We examined the LD-OFC results, including the induced symptoms and treatment required for positive LD-OFC results.

Results: The LD-Egg, LD-Milk, and LD-Wheat OFC groups comprised 68, 42, and 13 participants, respectively. The positivity rates for the LD-Egg, LD-Milk, and LD-Wheat OFC groups were 7%, 24%, and 0%, respectively. Patients predominantly exhibited skin symptoms, and most were treated with oral antihistamines alone. None of the patients experienced anaphylaxis or required adrenaline injections.

Conclusions: Infants aged <1 year with food allergies can safely undergo LD-OFCs by consuming low doses of causative foods. Avoiding the complete elimination of causative foods is an important strategy for managing infants with food allergies when initially introducing causative foods.

Keywords: cow's milk; food allergy; hen's egg; infants; low dose; oral food challenge; safety.