Beer-induced anaphylaxis: identification of allergens

Background: We report on a 21-year-old atopic woman who developed urticaria , angioedema of the face, and wheezy dyspnea shortly after drinking beer an d after eating a corn-made snack. Methods: Skin prick tests and specific IgE determinations to beer ingredien ts and cereal extracts were performed. Immunoblotting inhibition assays wer e carried out to investigate possible common allergens shared by barley and malt with corn. Results: Skin prick tests and specific IgE measurements with beer, barley, malt, wheat, corn, rye, rice, and oat flour were positive. Ten pollen-aller gic patients showed negative skin tests to beer. Double-blind, placebo-cont rolled, oral challenge tests with sodium metabisulfite and wheat flour were negative. Immunoblotting demonstrated several IgE-binding bands at 31-56 k Da in malt and barley extracts, and a major band at 38 kDa in the beer extr act. Immunoblot inhibition assays showed that malt extract was able to inhi bit most of the IgE-binding bands in wheat and corn extracts, whereas corn did not produce significant inhibition to barley and malt extracts. Conclusions: This patient developed type I hypersensitivity to barley/malt and corn. Although she also showed IgE reactivity to wheat and other cereal s, no symptoms were elicited upon ingestion of these cereals, probably indi cating latent sensitization to them.