Cross-sensitization between poppy seed and buckwheat in a food-allergic patient with poppy seed anaphylaxis.

The opium poppy, Papaver somniferum L., is the source of both poppy seeds and opium. The commercially available seeds are widely used as ingredients for various kinds of food. IgE-mediated sensitization to poppy seeds is rare, but, if present, clinical symptoms are usually severe. Cross-sensitizations between poppy seeds and other food allergens have been described with sesame, hazelnut, rye grain and kiwi fruit. We report the case of a 17-year-old female with an apparently food-allergic reaction after ingestion of a poppy seed cake. Allergological workup revealed a poppy seed anaphylaxis and led to the identification of a novel cross-sensitization with buckwheat.