Matrix effect on baked milk tolerance in children with IgE cow milk allergy.

Background: Children with IgE-mediated cow's milk allergy (IgE-CMA) often tolerate baked milk within a wheat matrix. In our study we evaluated the impact of wheat matrix and of little standardised cooking procedures on tolerance of baked milk. We also tested tolerance versus parmigiano reggiano (PR) and whey-based partially hydrolysed formula (pHF).

Methods: Forty-eight children with IgE-CMA were enrolled. They underwent prick-by-prick (PbP) and open oral food challenge (OFC) with baked cow's milk (CM), both within a wheat matrix (an Italian cake named ciambellone) and without (in a liquid form), with PR and with pHF. After a passed OFC, children continued to eat the food tolerated. In particular, after passed OFC with ciambellone, children were allowed to eat any food containing CM within a wheat matrix, with the only condition that it was baked at 180°C for at least 30min. Three months after, parents were asked to answer a survey.

Results: 81% of children tolerated ciambellone, 56% liquid baked CM, 78% PR and 82% pHF. Negative predictive value of PbP performed with tested foods was 100%. No IgE-mediated adverse reactions were detected at follow-up carried out by the survey.

Conclusions: Wheat matrix effect on tolerance of baked milk was relevant in slightly less than half of cases. If our results are confirmed by larger studies, a negative PbP will allow patients to eat processed CM without undergoing OFC. Moreover, in order to guarantee tolerance towards baked milk, strict standardised cooking procedures do not seem to be necessary.