Oral immunotherapy in children with IgE-mediated wheat allergy: outcome and molecular changes. 2014

Background: IgE-mediated wheat allergy affects around 0.5% of the population, and current management is based on avoidance. We propose an active intervention to promote tolerance in wheat-allergic children.

Objectives: To investigate the efficacy and safety of an oral immunotherapy (OIT) protocol with wheat to treat IgE-mediated wheat-allergic children.

Methods: Six wheat allergic patients assessed in a double-blind, placebo-controlled food challenge (DBPCFC) underwent wheat OIT with an up-dosing phase until 100 g of wheat was tolerated, followed by a 6-month maintenance phase. Tolerance to rye and oat was evaluated, as were specific IgE (sIgE) to wheat and other cereals and sIgE, sIgG4, and sIgG1 to a panel of wheat proteins (α-amylase and trypsin inhibitors, wheat lipid transfer proteins, gliadins, and glutenins).

Results: Threshold doses in the wheat DBPCFC ranged from 6.6 g to 96.6 g. Five out of 6 (83%) patients successfully finished the updosing phase in 3 to 24 days; after a 6-month maintenance phase, all the patients maintained good tolerance of 100 g of wheat daily. Only 6.25% of doses in the up-dosing phase elicited mild adverse reactions. All 5 patients who successfully finished the up-dosing phase tolerated rye after OIT, and all but 1 tolerated oat as well. The median baseline wheat sIgE was 47.5 kU_A/L, increasing to 84.55 kU_A/L after up-dosing and decreasing to 28.75 kU_A/L after 6 months of follow-up. None of the patients showed sIgE to 5-ω-gliadin, but α-amylase inhibitors were recognized by all patients. Specific IgG4 and sIgG1 increased in all patients.

Conclusions: Our wheat OIT protocol was safe, efficient, and rapid. In our population, α-amylase was the major allergen.

Key words: Food allergy. Immunotherapy. Food immunotherapy. Oral immunotherapy. Wheat allergy. Gluten. α-Amylase inhibitors. 5-ω-gliadin. Children. LTP.