Hereditary pulmonary emphysema.

To further elucidate the etiology of spontaneous pneumothorax (SP), a study was made of three nonsmoking patients who had experienced several episodes of chest radiograph-verified familial SP (FSP) and 11 unaffected relatives, 5 of whom were smokers and 6 of whom were never-smokers. Fourteen healthy subjects without SP served as a control group. All three groups underwent the same clinical, laboratory, and radiologic examinations, including CT scans of the lungs, with the aim of detecting any changes in the pulmonary parenchyma. Emphysema-like changes (ELCs) were detected on CT scans in each of the three patients with FSP. The unaffected relatives of the FSP patients showed no sign of FSP, but four of the six never-smokers and three of the five relatives who were smokers displayed pulmonary emphysema and ELCs on CT scans. No abnormalities were seen on pulmonary CT scans of the 14 control subjects. The present results indicate that ELCs and pulmonary emphysema may be genetically determined.