Study objective: To determine the relationship between airway hyperreactivity (AHR) and endobronchial involvement in patients with sarcoidosis.
Design: Prospective series of consecutive patients.
Setting: Pulmonary clinic of a military, tertiary-care teaching hospital.
Patients: Patients with newly diagnosed sarcoidosis.
Interventions: All patients undergoing bronchoscopy for the diagnosis of sarcoidosis underwent an 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. Only patients with histologic confirmation of sarcoidosis were included in the data analysis.
Measurements and results: The study cohort included 42 patients (57.1% were men, 61.9% were African American, and mean age [+/- SD] was 37.3 +/- 6.6 years). AHR was present in nine patients (21.4%), while EBB revealed nonnecrotizing granulomas in 57.1% of patients. All patients with AHR had positive EBB findings compared to 45.5% of individuals without AHR (p = 0.005). There was a trend toward lower lung volumes and flow rates in patients with AHR, but this did not reach statistical significance. The mean serum angiotensin-converting enzyme level was higher in patients with AHR (79.3 +/- 53.9 IU/L vs 37.5 +/- 26.7 IU/L, p = 0.05). No other clinical variable correlated with the presence of AHR.
Conclusions: AHR may be seen in patients with sarcoidosis. Endobronchial involvement significantly increases the risk for AHR and may play a role in the development of AHR in patients with sarcoidosis. Other clinical factors are not clearly associated with AHR in patients with sarcoidosis.