A case of millet allergy that developed into wheat-induced anaphylaxis by cross-reaction between millet and wheat antigens

Dear Editor, Millet allergy causes asthmatic attacks by inhalation, or urticarial symptoms by oral ingestion of antigens in patients sensitized to millet. It may result in anaphylactic reactions in severe cases. In Japan, millet is commonly consumed as birdseed or as natural health food, but little is known about its cross-reactivity with other grains and natural course of the sensitivity. We, here, report a case of millet allergy, where a patient developed severe allergic reactions against wheat by cross-reaction with millet antigens. Immunoblotting confirmed cross-reactivity between millet and wheat antigens, and the sensitization decreased after avoiding exposure to the antigens. Procedures of skin testing, protein extraction and immunoblotting are provided in the Supplementary Methods. A 59-year-old Japanese woman visited us with a history of allergic symptoms induced by wheat intake.