Background: Food allergy is treated by avoidance diets in order to prevent anaphylactic reactions and to cure chronic associated symptoms. However, the natural history is left unchanged.
Objective: To search for a beneficial effect of an oral desensitization protocol to allergenic foods in IgE-dependent milk or egg allergies in children.
Methods: 60 children with documented cow's milk allergy (13 months-6.5 years), and 90 children with egg allergy (12 months-8 years), were consecutively included after 6-12 months of avoidance diet, if a SBPCFC to 60 ml milk (60 ml) or to 965 mg of raw egg white was negative. They were randomized for uninterrupted avoidance or oral desensitization (group A or OD). Six months later, a new SBPCFC was performed with, up to 200 ml of milk or 7g of raw egg white. Prick tests and specific IgE levels were carried out simultaneously.
Results: Data were obtained for 57 children with CMA (30 A and 27 OD), and 84 children with EA (35 A and 49 OD). The two groups (AD or OD group) were similar with regard to means of ages, the size of PT wheals and the level of IgEs at baseline. MILK ALLERGY: A SBPCFC to milk was positive in 11.1% of those following OD vs. 40% after A (p < .025). The size of PT decreased after OD and increased after A (-3.4 mm vs. +0.84 mm; p < .002). EGG ALLERGY: The SBPCFC to egg was positive in 30.6% after OD vs. 48.6% after A (p < .1). After 6 months, in the OD group, the mean size of the PT and the level of specific IgE were significantly reduced compared to the A group. In the A group, the threshold of reactivity was often lower, or more serious symptoms were observed.
Conclusion: Oral desensitization helps the egg and milk allergic children to overcome their allergies. Since the avoidance of these foods is likely to increase sensitization as well as to lower the threshold of reactivity, an active treatment is required. Further attempts to standardize the procedures of oral desensitization are expected.