Exercise-induced "asthma" as a presentation of bronchial carcinoid.

Exercise-induced wheezing developed in a previously healthy 14-year-old boy. Chest radiographs revealed hyperlucency of the left lung. Bronchial tomography and bronchoscopy revealed a mass in the left mainstem bronchus, identified as a carcinoid tumor after surgical excision. The patient is now asymptomatic. Exercise-induced wheezing as the sole manifestation of this tumor has not been previously reported.