Pulmonary function and alpha-1-antitrypsin levels in patients after so-called idiopathic spontaneous pneumothorax.

The subpleural blebs found in patients with so-called idiopathic spontaneous pneumothorax suggest that pneumothorax could possibly be an early manifestation of pulmonary emphysema in these subjects. In order to investigate this hypothesis, fifty-six young adults (32 +/- 9 yr; 45 men and 11 women) were examined after idiopathic spontaneous pneumothorax. All were apparently healthy with no history of pulmonary disease. Physical and X-ray examination were normal. The episode of pneumothorax was the only sign of lung pathology. A control group of 20 healthy people was also studied. The mean age and smoking habits in the patients and control groups were similar. Only four patients (7%) revealed definite evidence of emphysema, consisting of a reduction of diffusing capacity, decrease of lung recoil pressure and a secondary reduction of forced expiratory flow at 50% of vital capacity. Serum alpha-1-antitrypsin levels in these patients were normal.