Nasal congestion, urticaria, and angioedema caused by an IgE-mediated reaction to sodium metabisulfite.

A case of metabisulfite-induced anaphylaxis is presented in which convincing evidence of an IgE-mediated mechanism of action was found. The patient demonstrated urticaria, angioedema, nasal congestion, and apparent nasal polyp swelling following provocative challenge with sodium metabisulfite. Skin test to metabisulfite was positive as was a basophil histamine release test when the patient's cells were incubated with metabisulfite. A review of metabisulfite-induced allergic reactions in which an IgE-mediated mechanism has been demonstrated is presented.