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

Background. Children with IgE-mediated hen’s egg allergy (IgE-HEA) often tolerate 29 Baked egg within a wheat matrix. 30 Objective. To evaluate the influence of wheat matrix and the effects of little standardized 31 cooking procedures on baked egg tolerance. 32 Methods. 54 children with IgE-HEA were enrolled. They underwent prick by prick (PbP) 33 tests and open oral food challenges (OFC) performed with baked HE within a wheat matrix 34 (a home-made cake, locally called ciambellone), baked HE without a wheat matrix (in a 35 form of an omelette, locally named frittata) and boiled HE. Three months after passing 36 ciambellone OFC, patients parents were asked to answer a survey. 37 Results. 88% of children tolerated ciambellone, 74% frittata, 56% boiled HE. Negative 38 predictive value of PbP performed with ciambellone, frittata and boiled HE was 100%. No 39 IgE-mediated adverse reactions were detected at follow-up carried out by the survey. 40 Conclusions. Wheat matrix seemed to be relevant only in few cases. If our results will be 41 confirmed by larger studies, a negative PbP with ciambellone, frittata or boiled HE will allow 42 patients with IgE-HEA to eat these foods without undergoing OFC. Moreover, our study 43 showed that strict standardized cooking procedures do not seem to be essential, in order to 44 guarantee tolerance towards baked HE.