Children With Tolerance Of Baked Egg Demonstrate Higher Eliciting Doses In Challenges To Native Egg

Rationale: It is well recognized that some children with egg and milk allergy tolerate these foods in the heated or baked form. Our study defines differences in median eliciting dose for children undergoing native egg and milk oral food challenges (OFC) by previous tolerance and exposure to baked forms.

Methods: A retrospective chart review of 569 patients, ages 1-18y, who underwent OFC to native egg and milk from 1/2012 through 12/2015. The Mann-Whitney test was used to compare median eliciting doses for each group. Demographics, OFC results (dose, reaction), skin prick test and specific IgE were collected.

Results: For native egg, the median eliciting dose in children who previously reacted to baked egg (n=35) was 0.50g (0.13g-9.88g), compared to 3.50g (0.13g-15.80g) in children who tolerated baked egg (n=235) (p=0.0064) and 0.38g (0.13g-3.88g) in those with no exposure to baked egg (n=72)(p<0.0001). For native milk, median eliciting dose in those who had reacted to baked milk (n=40) was 2.32g (0.07g-8.50g), compared to 5.99g (0.15g-12.40g) in those with baked tolerance (n=105) (P=0.318), and 4.49g (0.44g-17.70g) in those with no exposure to the baked form (n=82) (P=0.574). History of no exposure or reaction to baked egg was associated with epinephrine use for 59% and 63% of OFC reactions respectively, but only 42% in those who tolerated baked egg.

Conclusions: Children who tolerate baked egg react at higher eliciting doses and require epinephrine less commonly when challenged to native forms. There was no significant difference in eliciting dose to native milk based on baked milk exposure history.