Mechanisms of intrinsic asthma

The phenomenon of intrinsic or nonatopic asthma continues to raise questions about the possible role of IgE-mediated mechanisms in asthma pathogenesis. With the current availability of anti-IgE therapy for asthma, clarification of this issue has never been more timely and relevant.

This article summarizes recent studies for and against the proposition that IgE-mediated mechanisms play a critical role in asthma pathogenesis. These data comprise epidemiological studies and recent molecular studies, suggesting that IgE synthesis may take place in the bronchial mucosa of patients with nonatopic asthma, despite the fact that allergen-specific IgE is not detectable in the periphery by standard skin prick testing.

At present, available data do not allow a firm conclusion to be made as to whether or not IgE-mediated mechanisms play an obligatory role in asthma pathogenesis. Implications for the future therapy of nonatopic asthma in either case are discussed, as well as some suggestions for further research.