Update on wheat hypersensitivity.
OBJECTIVE
Wheat is among the six foods responsible for approximately 90% of food allergies in children, and in recent years wheat has been increasingly recognized as a cause of food-dependent, exercise-induced anaphylaxis. Wheat flour is an important cause of baker's asthma, a well-known occupational respiratory allergy to inhaled flour. This review outlines the diverse clinical manifestations of IgE-mediated wheat hypersensitivity and summarizes recent advances in characterization of clinically significant allergens.


RESULTS
Only a few of the numerous wheat proteins recognized by IgE of sensitized individuals have been characterized at the molecular level. Characterized allergens causing baker's asthma include several water/salt-soluble wheat proteins, however sensitization patterns show a great degree of individual variation. The insoluble gliadins have been implicated in IgE-mediated allergy to ingested wheat, and omega-5 gliadin has been identified as a major allergen in wheat-dependent, exercise-induced anaphylaxis. The presence of IgE to purified omega-5 gliadin in children was highly predictive of immediate clinical symptoms on oral wheat challenge.


CONCLUSIONS
Diagnostic skin prick and in-vitro tests measuring sensitization against water/salt-soluble wheat proteins have poor predictive values. Quantification of gliadin-specific IgE in serum or skin prick testing with gliadin could serve as an additional tool in the diagnostic work-up of allergy to ingested wheat.
Palosuo
Kati
K
Department of Dermatology, University of Helsinki and Hospital for Skin and Allergic Diseases, Helsinki, Finland. kati.palosuo@hus.fi
D000485:Allergens / Q000009:adverse effects / Q000145:classification / Q000276:immunology; D000707:Anaphylaxis / Q000175:diagnosis / Q000209:etiology / Q000276:immunology; D000918:Antibody Specificity / Q000276:immunology; D003429:Cross Reactions / Q000276:immunology; D005433:Flour / Q000009:adverse effects / Q000145:classification; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood / Q000276:immunology; D021182:Wheat Hypersensitivity / Q000175:diagnosis* / Q000209:etiology* / Q000276:immunology
D000485:Allergens; D007073:Immunoglobulin E