Bilateral bronchial anomaly. A pathogenetic factor in spontaneous pneumothorax.

Flexible fiberoptic bronchoscopy (FFB) was performed in 26 never-smokers with healed spontaneous pneumothorax (SP) with the aim of detecting and localizing any bronchial obstruction, including congenital anomaly. In a case-control study these patients were compared with a consecutive, randomly sampled, control group of 41 patients who were undergoing FFB for respiratory symptoms but who had not had a SP. In both groups the endobronchial anatomy with respect to such anomalies, which could be classified as disproportionate bronchial anatomy, an accessory bronchus, and/or a missing bronchus, was compared with normal anatomy. All except one of the 26 patients with SP but only four of the 41 control patients without SP had such bronchial anomalies bilaterally. This corresponds to an odds ratio of 231 (95% confidence interval, 24 to 880; p < 0.001). The significantly higher frequency of bilateral bronchial anomalies in never-smokers with SP suggests that a virtual prerequisite for the occurrence of SP has been found. However causal links between the probably congenital bronchial anomalies and SP have not yet been identified.