Hyperresponsiveness to Boiled Egg Yolk in Early Life Leads to Prolonged Egg Allergy.

Hen's egg is the most common allergen in IgE-mediated food allergy among children in Japan. Although the majority of patients with egg allergy can eat heated egg yolk safely because of its low allergenicity, severely allergic patients show an immediate-type reaction to heated egg yolk. We hypothesized that patients with hyperresponsiveness to boiled egg yolk may have difficulty in acquiring tolerance to egg. The purpose of this study was to examine the prognosis of patients with hyperresponsiveness to boiled egg yolk. Data from 121 patients with egg allergy who underwent oral food challenge (OFC) with boiled egg yolk between January 2012 and December 2013 were analyzed retrospectively. The proportion of patients who could consume heated whole egg 3 years after OFC was 15.4% in the OFC-positive group and 75.8% in the OFC-negative group. Hyperresponsiveness to boiled egg yolk in early life might lead to prolonged egg allergy in children. This finding might aid in the selection of an appropriate population requiring practical immunotherapy.