LARGE AIRWAY CONSTRICTION IN ALLERGIC RHINITIS

[摘要] Extensive pulmonary function tests, including most of the sensitive new techniques capable of detecting small airways obstruction, were performed in 16 asymptomatic patients with allergic rhinitis and 31 normal control subjects. Mean flow rates, lung volumes, and results of tests measuring airways closure, distribution of ventilation and diffusing capacity for CO lalveolar volume did not differ significantly between the groups. Airways resistance (RAW) was significantly higher and specific conductance (SGAW) was significantly lower in subjects with rhinitis. Following administration of nebulized isoproterenol, RAW decreased (P < 0.001) and SGAW increased (P < 0.001) to mean values statistically indistinguishable from results obtained in control subjects. Individual results were normal for all tests except RAW and SGAW which were abnormal in 3 subjects with rhinitis. Asymptomatic subjects with allergic rhinitis have large airway (trachea and/or major bronchi) narrowing due to bronchoconstriction and no evidence of diffuse or small airways obstruction.