Successful oral desensitization in children with cow's milk anaphylaxis: Clinical and laboratory evaluation up to nine-years follow-up.

INTRODUCTION: Cow's milk protein allergy (CMPA) is the most common food allergy in children worldwide. Some children have severe and persistent CMPA, with near-fatal reactions after exposure to trace amounts of cow's milk-proteins (CMP). Strict avoidance diet is difficult, negatively affects quality of life and represents a conservative approach. Therefore, different therapeutic strategies are necessary. OBJECTIVE: We aimed to assess long-term efficacy and safety of oral immunotherapy (OIT) in children with severe and long-lasting IgE-mediated CMPA. MATERIALS AND METHODS: The authors present four case reports of patients with CMPA who underwent CMP-OIT, that have been under long-term follow-up up to nine years. We provide information about the clinical and laboratory evaluation. Skin prick tests (SPT), specific IgE and IgG4 were performed before, during, and after OIT. Immune profile after OIT was assessed by flow cytometry (lymphocyte subsets, regulatory T and B cells). RESULTS: The success rate was 100%, and all patients currently have a free diet with minimal diary ingestion of 200mL CMP or equivalent. Specific IgE levels and SPT to CMP have progressively decreased, and specific IgG4 levels have increased. CD4+CD25+CD127-/dim regulatory T cells were increased after OIT. CONCLUSIONS: OIT ensured a clinical tolerance state after up to nine years, confirmed by both clinical and immune profile, allowing a diet without restrictions, with high satisfaction from patients and caregivers. We emphasize that OIT should be performed only by allergy experts in the hospital setting, and that only motivated families should be enrolled, since it is essential to ensure CMP daily intake at home.

Specific oral immunotherapy in food allergic patients: transient or persistent tolerance?

INTRODUCTION: The first therapeutic choice for food allergy is avoidance of the responsible food, but when this approach is not possible, specific oral desensitization could be considered as a good alternative. It is not clear yet whether the acquired tolerance is transient or persistent. AIM: We report on a subset of 13 patients of a larger study, treated successfully with specific oral tolerance induction who experienced secondary loss of tolerance after a period of allergen avoidance. MATERIAL AND METHODS: Thirteen patients affected by IgE-mediated food allergy: to cow milk (3 patients), to hen egg (3 patients), to cod fish (2 patients), to peanuts (1 patient) and to corn (1 patient) confirmed by a complete allergological workup and a double-blind placebo-controlled food challenge (DBPCFC), were treated with sublingual-oral desensitization. After the interruption of the maintenance phase, the laboratory tests were performed and 12 of 13 patients underwent DBPCFC. RESULTS: Oral specific desensitization was completed successfully in all the 13 reported patients. At different times after the end of treatment, they decided, on their own initiative, to stop the ingestion of incriminated food. A new food allergen re-exposure caused adverse reactions in 12 of 13 patients. The detection of specific IgE and IgG4 during the period of allergen avoidance showed an increase in or a stable level of specific IgE and a decrease in specific IgG4 in 8 patients. CONCLUSIONS: According to our experience, the tolerance obtained through the desensitizing treatment is transient and so the regular allergen intake is necessary for its maintenance.