Matrix effect on baked egg tolerance in children with IgE-mediated hen's egg allergy

Abstract

Background: Children with IgE-mediated hen's egg allergy (IgE-HEA) often tolerate baked egg within a wheat matrix.

Objective: To evaluate the influence of wheat matrix and the effects of little standardized cooking procedures on baked egg tolerance.

Methods: Fifty-four children with IgE-HEA were enrolled. They underwent prick-by-prick (PbP) tests and open oral food challenges (OFC) performed with baked HE within a wheat matrix (a home-made cake, locally called ciambellone), baked HE without a wheat matrix (in the form of an omelet, locally named frittata) and boiled HE. Three months after passing ciambellone OFC, parents were asked to answer a survey.

Results: About 88% of children tolerated ciambellone, 74% frittata, and 56% boiled HE. Negative predictive value of PbP performed with ciambellone, frittata, and boiled HE was 100%. No IgE-mediated adverse reactions were detected at follow-up carried out by the survey.

Conclusions: Wheat matrix seemed to be relevant only in few cases. If our results will be confirmed by larger studies, a negative PbP with ciambellone, frittata, or boiled HE will allow patients with IgE-HEA to eat these foods without undergoing OFC. Moreover, our study showed that very strict standardized cooking procedures do not seem to be essential, to guarantee tolerance toward baked HE.

Keywords: baked egg; cooking standardization; hen's egg allergy; matrix effect; negative predictive value; prick-by-prick test.