Pediatric Eosinophilic Esophagitis (pedEoE): Effect of Allergen Heat Denaturation on EoE Remission: a Pilot Trial

Overview

The objective of the study is to study whether the introduction of heated food products (more specifically heated hen's egg and/or cow's milk) in children with EoE would be possible without re-occurrence of the eosinophilic inflammation, while the intake of less heated products might cause disease recidive. Moreover, we would like to study whether the gradual re-introduction of less heated products after the most heated form is tolerated, could lead to tolerance induction in EoE.

If inclusion criteria are met, after obtaining informed consent from the parents (and when old enough, assent from the children) children with cow's milk and/or hen's egg induced pedEoE will be included in this pilot trial. Baseline blood will be obtained before in-house OFC procedure and serum will be stored for specific IgG4 analysis. In parallel, PBMCs will be isolated and stimulated in vitro with heat denatured proteins. B cells will be stained by 4-laserflow cytometry. IgG4 production in supernatants will be studied by ELISA (specific IgG4 by Immunocap 100). This procedure will be repeated during each gastroscopy. Children will be provoked in-house, based on the written procedure available for heated egg or cow's milk provocation. Afterwards, they will introduce heated egg by cake or 20' boiled cow's milk at least three times a week for 8 weeks and will return to the hospital for a gastroscopy with biopsies. EoE remission will be studied on biopsies of the upper and lower esophagus by eosinophil staining within the routine anatomopathological laboratory within our hospital. If remission remains, subjects will be invited to introduce less heated hen's egg or cow's milk for 8 weeks, after which they will return to the hospital for the second gastroscopy with similar procedure. This is repeated three times until 4' soft-boiled egg or 5' boiled cow's milk is introduced for 8 weeks. When remission remains after this introduction, the children and parents are offered the possibility to terminate the study or to introduce either raw egg (tiramisu or chocolate mousse) or uncooked UHT-treated cow's milk for 8 weeks after which gastroscopy with biopsies will be performed. If remission is lost, they will return to the strict avoidance diet for at least 10 weeks after which they will return to the hospital for their second gastroscopy. Upon remission after avoidance, the children will remain eligible for another heat denatured food challenge (when on diet for both).