Histamine and its release from nasal polyps: preliminary communication.

Two hundred consecutive patients admitted for polypectomy had no evidence of an increased incidence of allergic disorders. Mast cell degranulation was found on transmission electron microscopy and this resulted in considerable quantities of histamine in polyp extracellular fluid (124-7300 ng/ml). RAST levels of allergen-specific IgE to house-dust mite and mixed-grass pollens were raised in 4 out of 28 cases in polyp fluid, and in only one matched serum. In vitro challenge of polyp tissue with allergen extract and anti-IgE suggested an IgE-mediated response in only 4 of 36 patients.