Wheat food allergy in adults has a favorable prognosis
Scibilia J1, Rossi CM1, Losappio LM1, Mirone C1, Farioli L2, Pravettoni V3, Pastorello EA1
1Unit of Allergology and Immunology, Dipartimento Medico Polispecialistico, ASTT Grande Ospedale Metropolitano Niguarda, Milan, Italy
2Department of Laboratory Medicine, ASST Grande Ospedale Metropolitano Niguarda, Milan, Italy
3Clinical Allergy and Immunology Unit, Foundation IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy
J Investig Allergol Clin Immunol 2019; Vol. 29(2)
Background: Wheat ingestion can lead to different disorders such as IgE-mediated food allergy and wheat-dependent exercise-induced anaphylaxis (WDEIA), associated with impaired quality of life and significant morbidity. Allergy to wheat is relatively benign in children, however its natural history in adults is still unknown.
Objective: We evaluated the natural history of wheat hypersensitivity in atopic patients with adult-onset wheat- allergy assessed by placebo-controlled-challenge.
Methods: We enrolled 13 patients from an initial cohort of adult patients (mean age 40 years) with IgE-mediated wheat allergy. After diagnosis the patients observed a wheat-free diet and were followed as outpatients for 5-years to evaluate for wheat-exposure. At the end of the follow-up, wheat-IgE titers were determined and a second wheat-challenge was performed.
Results: 10 out of 13 patients took part in the study. The mean period of wheat avoidance was 4.2 years. 3 patients had spontaneously re-introduced wheat before the second evaluation, after a mean of 28 months (IQR 18-36 months), with only mild gastrointestinal discomfort at wheat reintroduction. At the end of follow-up, 9/10 patients were wheat-tolerant. 2 patients had a history WDEIA. A reduction of IgE levels, median IgE from 2.77 kU/l (IQR 0.35-100 kU/L) at diagnosis to 0.88 kU/l (IQR 0.1-20.8 Ku/L) was observed. No statistical correlation was found between IgE and negative challenge outcome.
Conclusion: IgE-mediated wheat allergy in adults is benign and represents a temporary break in the gastrointestinal tolerance. Future studies may improve our knowledge of wheat allergens, routes and factors leading to sensitization and prognostic biomarkers.
Key words: Wheat allergy, Adult food allergy, Food tolerance, Double-blind placebo-controlled food challenge