Allergic rhinitis with negative skin tests: Does it exist?

Nonallergic rhinitis (NAR) is a common disorder encountered by the practicing allergist/immunologist. The immunopathology of allergic rhinitis (AR) and NAR share several characteristics. Patients with AR have allergen-specific IgE demonstrable both systemically (e.g., positive skin tests) as well as local IgE produced in the nasal mucosa. A few studies have evaluated patients with NAR using nasal provocation with allergen. Some, but not all, studies have revealed positive allergen challenge in these nonallergic subjects with negative skin tests. This article reviews these studies and highlights the differences in methodology. Further refinements and standardization of nasal provocation techniques may be required before proving that localized IgE-mediated allergy occurs in patients with negative skin tests.