Clinical utility of IgE antibodies to ω-5 gliadin in the diagnosis of wheat allergy: a pediatric multicenter challenge study.

Clinical Research Center for Allergy and Rheumatology, National Hospital Organization, Sagamihara National Hospital, Sagamihara, Japan.
International Archives of Allergy and Immunology (Impact Factor: 2.25). 12/2011; 158(1):71-6. DOI: 10.1159/000330661
Source: PubMed

ABSTRACT There are contradictory results regarding the clinical usefulness of the determination of IgE antibodies to ω-5 gliadin in children with a suspicion of wheat allergy (WA).
The study comprised 311 children and young adults with suspected wheat intolerance treated at three separate pediatric clinics and, with the exception of 25, were found to be positive in specific IgE antibody determinations to wheat. Their ages ranged from 6 months to 20.4 years (median age, 2.3 years). Possible relationships between IgE antibodies to ω-5 gliadin and a physician's diagnosis of WA and challenge symptoms were studied.
The mean concentration of IgE antibodies to ω-5 gliadin was 1.2 kU(A)/l in WA patients and <0.35 kU(A)/l in patients without WA (p < 0.0001). Seventy-two percent of the WA patients had positive ω-5 gliadin levels and 75% of the patients without WA had negative levels. Logistic regression showed a significant relationship between the probability of WA and the concentration of IgE antibodies to ω-5-gliadin with a 2.6-fold (95% CI: 2.0-3.3) increased risk. Age was an important factor to consider as the risk of WA increased 5.4-fold (95% CI: 1.4-21) for children ≤1 year of age and 2.5-fold (95% CI: 2.0-3.2) for children >1 year of age with increasing levels of IgE.
Detection of IgE to ω-5 gliadin seems to be associated with responsiveness to the challenge test and is particularly useful in infants with a suspicion of WA.

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