Endobronchial Biopsy for Sarcoidosis: a Prospective Study

Study Objectives: To determine the yield of endobronchial biopsy (EBB) for suspected sarcoidosis, and to evaluate if EBB increases the diagnostic value of fiberoptic bronchoscopy (FOB) when added to transbronchial biopsy (TBB).

Design: Prospective study of consecutive patients.

Setting: Pulmonary clinic of a tertiary-care, academic medical center.

Patients: Patients consecutively referred for suspected pulmonary sarcoidosis.

Interventions: All patients having FOB performed underwent an evaluation that included history, physical examination, a chest radiograph, and spirometry. During FOB, airway appearance was recorded and both TBB and EBB were performed in a standardized fashion. Six TBB specimens were obtained, as were six EBB samples. For patients with abnormal-appearing airways, four specimens were obtained from the abnormal-appearing airways 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 finding was considered positive if it demonstrated nonnecrotizing granulomas with special stains that were negative for fungal and mycobacterial organisms.

Measurements And Results: The study cohort included 34 subjects (mean +/- SD age, 37.9 +/- 6.8 years; 58.8% were male; 64.7% were African American). EBB findings were positive in 61.8% of patients, while TBB showed nonnecrotizing granulomas in 58.8% of subjects. The addition of EBB increased the yield of FOB by 20.6%. Although EBB findings were more frequently positive in abnormal-appearing airways (p = 0.014), EBB provided diagnostic tissue in 30.0% of patients with normal-appearing endobronchial mucosa. There were no complications resulting from the addition of EBB to TBB.

Conclusions: Endobronchial involvement is common in sarcoidosis. EBB has a yield comparable to TBB and can safely increase the diagnostic value of FOB. Pulmonologists should consider routinely performing EBB in cases of suspected sarcoidosis.