D2.212 - Assessment of Adverse Reactions in Children with IgE-Mediated Food Allergy Following Desensitization Protocols

IgE-mediated food allergy is the most common type of food allergy and poses significant danger due to the immediate onset of adverse reactions. The incidence of food allergies in children is rising steadily. The primary method of management is the avoidance of the offending food. To address this, desensitization protocols, such as oral immunotherapy (OIT), have been developed and tested in recent years. These protocols aim to promote immediate tolerance and allow for the gradual reintroduction of these allergens into the child's diet. Desensitization protocols generally consist of three phases: T1 (starting dose, duration: 1-2 days), T2 (dose escalation/target dose, duration: 6 months), and T3 (maintenance dose, duration: 6 months). 

This study includes 12 children, aged 2-10 years, who are being followed at the Pediatric Allergy Unit of the University Hospital of Ioannina in Greece for IgE-mediated food allergy. The diagnosis is confirmed by open food challenge, positive skin prick tests (≥3mm), and elevated allergen-specific IgE levels (≥0.35 IU/L). Children with uncontrolled asthma, severe atopic dermatitis, or serious comorbidities are excluded from the study. All participants will undergo a desensitization protocol over the course of one year. During the desensitization process, adverse reactions were closely monitored to assess both their frequency and severity. Also specific biomarkers, including biofluid metabolites, total IgE, allergen-specific IgG4 and IgE, eosinophils, basophils will be tested to assess response and prognosis. Biomarker levels will be measured at baseline (T0), at 6 months (T6), and at 12 months (T12).

A total of 12 pediatric patients (6 boys, 6 girls) participated in the study, aged 2-10 years. The desensitization protocol was administered to patients with food allergies to cow's milk (4 patients), egg white (1 patient), sesame (3 patients), tree nuts (2 patients), and a multi-allergen protocol (2 patients). Seventy percent of the patients experienced mild allergic reactions, primarily during the initial phases of desensitization (≤1/4 of the target dose). The remaining 30% of patients had moderate to severe reactions, which also occurred mainly during the initial dose escalation. Of the total number of patients, 4 are in the maintenance phase of the desensitization protocol, while 8 are still in the dose escalation phase (≥1/2 of the target dose). 

The majority of allergic reactions during desensitization in patients with IgE-mediated food allergies are mild and occurred during the early phases-an encouraging finding for the successful completion of desensitization and the achievement of tolerance. These findings support the potential of OIT as a promising approach for the management of food allergies in children.