Chronic airways obstruction in pulmonary sarcoidosis: its poor response to bronchodilators.
Emphysema, chronic bronchitis, asthma, and cystic fibrosis are often cited as examples of chronic airways obstruction, while sarcoidosis is typically restrictive. Approximately 15 percent of sarcoidosis patients, however, have airways obstruction clinically characterized by wheezing with granulomatous involvement of airways. Since the majority have Stage IV disease by chest radiograph, their lungs usually have honey-combining with pulmonary fibrosis, adhesions, cavities, and mediastinal distortion.Patients had a mixed ventilatory defect, but obstruction of large airways was present as shown by decreased specific airways conductances. Small airways obstruction was also present as shown by low instantaneous flows at the terminal portion of the maximum expiratory flow-volume curve and diminished helium response of this curve. The closing volume, however, was not very sensitive. Radioactive xenon washout from ventilation lung scans and N2 washout from the lungs were prolonged in patients with worse disease.The authors conclude that the obstructive type of physiologic pattern is more frequent than recognized in sarcoidosis, which like that of cystic fibrosis has some restrictive element and is characterized by poor reversibility to bronchodilators. A trial period of beclomethasone dipropionate aerosol was not helpful in two patients. Relief of this distressing airways obstruction continues to pose a challenging problem in management.