Perennial rhinitis: an analysis of skin testing, serum IgE, and blood and smear eosinophilia in 201 patients.

Allergen skin testing, eosinophil counting in blood and nasal smear and serum IgE determination were performed in patients with simple perennial rhinitis, and in patients with rhinitis and asthma. The results were compared with those obtained in normal controls. As a positive skin test was demonstrated in 40% of patients with simple rhinitis and in 88% of patients with rhinitis and asthma, skin testing is considered relevant in all patients with perennial rhinitis. While blood eosinophil count and serum IgE level were elevated in a fair proportion of asthmatic patients, only a few subjects with simple perennial rhinitis had an elevated level, and the diagnostic values of these tests is questionable. On the other hand, examination of a nasal smear for eosinophils could usually separate the patients from the controls. The study emphasizes the importance of making a distinction between simple perennial rhinitis and perennial rhinitis associated with other symptoms and diseases.