From respiratory sensitization to food allergy: Anaphylactic reaction after ingestion of mushrooms (Agaricus bisporus)

We report a case of a 38-year-old mold-allergic patient who developed episodes of generalized urticaria and systemic anaphylactic shock immediately after ingesting button mushrooms. A manganese-dependent superoxide dismutase (MnSOD) and a NADP-dependent mannitol dehydrogenase (MtDH) from Agaricus bisporus mushroom were identified as patient-specific IgE-binding proteins. Cross-reactivity between A. bisporus MnSOD and mold aeroallergens was confirmed. We conclude that prior sensitization to mold aeroallergens might explain severe food reactions to cross-reacting homologs mushroom proteins.