Single NSAID hypersensitivity is associated with atopic status.

BACKGROUND The relationship between hypersensitivity to NSAID and atopic status is still incompletely defined. Previous studies found a high prevalence of atopic diseases in multiple NSAID reactors. The present study aimed to investigate whether this is the case also in Italian adults hypersensitive to NSAIDs. METHODS Skin tests with a large panel of seasonal and perennial airborne allergens were carried out in 252 patients with a clear-cut history of acute urticaria induced by nonsteroidal anti-inflammatory drugs. Patients were classified as single or multiple NSAID reactors based on clinical history, presence/absence of chronic urticaria, re-challenge with the reported offending drug in case of doubt history, and oral challenges with aspirin or propionic acid derivatives. RESULTS Single NSAID reactors showed a much higher prevalence of atopic diseases than multiple NSAID reactors either with or without chronic urticaria (61% vs 19% and 19%, respectively; p < 0.001). CONCLUSION As a difference from previous reports, in Italian patients hypersensitive to NSAID atopy is much more prevalent among single reactors, a finding that indirectly supports the possible IgE-mediated origin of this type of adverse drug reaction.