Anaphylaxis to Agaricus bisporus ingestion

A 33-year-old male with house dust mite allergic rhinitis and asthma reported an episode of facial and lip angioedema, dyspnea, cough and dysphagia at the age of 25, minutes after eating a mushroom ( Agaricus bisporus ) pizza. He denied any drug intake, hymenoptera stings or other possible triggers, and no identifiable cofactors were present. Since then he avoided all types of mushrooms, however an accidental contact occurred with mushroom sauce that resulted in angioedema of the lip within minutes. The allergy workup included measurements of total IgE and specific IgE to mushroom, and skin prick test to aeroallergens sources, possible food allergen sources and mushroom extract, a prick to prick test with raw and cooked A. bisporus , in addition to a SDS-PAGE and immunoblotting assay. The study revealed a specific IgE to mushroom of 0.76kUA/L positive skin prick test to mushroom extract, and prick to prick test positive to white and brown A. bisporus (raw and cooked). The immunoblotting identified two IgE binding proteins with 10kDa and 27kDa. We report a case of A. bisporus anaphylaxis probably due to primary mushroom sensitization. We detected two IgE-reactive proteins with 10kDa and 27kDa as possible culprit allergens.