INTERVENTIONAL PULMONOLOGY IN OTHER JOURNALS: Commentary on Selected Publications
Endobronchial involvement and airway hyperreactivity in patients with sarcoidosis.
Chest 2001;120:881–6. Shorr AF, Torrington KG, Hnatiuk OW. Pulmonary and Critical Care Medicine Service, Walter Reed Army Medical Center, Washington, DC U.S.A.
This prospective study of a series of 42 consecutive patients (57% men; 62% African–American; mean age, 37.3 ± 6.6 years; 40 of 42 patients were never smokers) was designed to determine the relationship between airway hyperreactivity (AHR) and endobronchial involvement in patients with newly diagnosed sarcoidosis. All patients scheduled for bronchoscopy for the diagnosis of sarcoidosis underwent evaluation that included history, physical examination, chest radiography, and spirometry. Bronchoprovocation testing was done using methacholine. During bronchoscopy, six endobronchial biopsy (EBB) specimens were obtained. In patients with abnormal-appearing airways, four specimens were obtained from abnormal areas and two specimens were obtained from the main carina. In patients with normal-appearing airways, four specimens were obtained from a secondary carina and two specimens were obtained from the main carina. A biopsy specimen was considered positive if it demonstrated nonnecrotizing granulomas with special stains that were negative for fungal and mycobacterial organisms. The results showed that the mean serum angiotensin-converting enzyme level was higher in patients with AHR. A stage I chest radiograph was noted in 28 patients, and stage II and stage III chest radiographs were seen in 12 patients and 2 patients respectively. Five patients (11.9%) had extrapulmonary sarcoidosis at the time of presentation. The diagnosis of sarcoidosis was by EBB alone in 8 patients and by bronchoscopic lung biopsy alone in 12 patients. In 16 instances both EBB and bronchoscopic lung biopsy findings were positive. In the remaining patients, diagnostic tissue was obtained via mediastinoscopy. AHR was present in nine patients (21.4%) whereas EBB revealed nonnecrotizing granulomas in 57.1% of patients. All patients with AHR had positive EBB findings compared with 45.5% of individuals without AHR (p = 0.005). The authors conclude that AHR may be seen in patients with sarcoidosis, and that endobronchial involvement increases significantly the risk for AHR and may play a role in the development of AHR in patients with sarcoidosis. The overall rate of endobronchial involvement in sarcoidosis is approximately 50%. The overall incidence of AHR has varied from 5 to 83%. The mechanism of AHR in patients with sarcoidosis is not understood. The clinical importance of identifying AHR in patients with sarcoidosis relates to the overall prognosis. Chronic airflow obstruction has been shown to be associated with a worse prognosis in patients with sarcoidosis (Eur Respir J 1993;6:349–53 ). The study by Shorr et al. suggests that AHR is present in 20% of patients with newly diagnosed pulmonary sarcoidosis, and the presence of AHR in patients with sarcoidosis is highly indicative of endobronchial involvement by sarcoidosis.