Background: Narrow band imaging (NBI) during flexible bronchoscopy can highlight subtle anomalies in the airway mucosa. NBI-guided endobronchial biopsy (EBB) has not been compared to white light bronchoscopy (WLB)-guided EBB in suspected sarcoidosis.

Methods: This was an open-label, randomised controlled superiority trial. We included consecutive adult subjects with clinico-radiological presentation consistent with sarcoidosis. We randomised them 1:1 to undergo EBB under real-time visualisation with NBI (intervention) or WLB (control). Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) and transbronchial lung biopsy (TBLB) were also performed. A final diagnosis of sarcoidosis was made based on complete clinico-radiologic and pathologic information. The primary outcome was the diagnostic yield of EBB (demonstration of granulomatous inflammation in EBB specimen in subjects with a final diagnosis of sarcoidosis)

Results: Of the 150 subjects (mean age, 43.1 years; 70 [46.7%] women) randomised, a diagnosis of sarcoidosis was made in 126 subjects (66 in NBI, 60 in WLB). Endobronchial nodules were observed in 14/66 (21.2%) subjects in the NBI group compared to 17/60 (28.3%) in WLB group. The diagnostic yield of granulomas on EBB was similar in the NBI (37.9% [25/66]) and WLB (43.3% [26/60]) groups (p=0.53). The duration of procedure was not different between the study groups (p=0.18). Airway bleeding occurred in 14 (21.2%) and 5 (8.3%) subjects in the NBI and WLB subjects, respectively (p=0.04).

Conclusions: We did not find NBI to be superior to WLB in the yield of granulomas on endobronchial biopsy in sarcoidosis.