Introduction The utility of endoscopic ultrasonography in the diagnosis of sarcoidosis was shown in the GRANULOMA trial.1 However, in the study, two thirds of samples were obtained using Endoscopic Ultrasound (EUS) via the gastrointestinal tract, and one third by Endobronchial Ultrasound (EBUS). Since this does not reflect typical practice in many areas, we assessed the diagnostic sensitivity of EBUS in suspected sarcoidosis and whether sampling nodes not accessible by EUS confers benefit.
Methods We retrospectively collected data relating to 128 consecutive patients in two separate experienced centres, who underwent EBUS over a 3 year period (2011–2013) with a pretest differential diagnosis of sarcoidosis. Final diagnosis was based on decision at subsequent clinic review.
Results 129 EBUS procedures were performed in 128 patients (57% male, mean (range) age 49 (22–79) years. 221 nodal stations were sampled (median of 2 stations each patient) with no significant complications. Concurrent trans-bronchial biopsy (TBB) was carried out in 30 patients and endobronchial biopsy (EBB) in 10.
Overall diagnostic sensitivity (for each biopsy procedure alone) was as follows: EBB 44%, TBB 50%, EBUS 71%, while combining EBUS with EBB/TBB conferred a sensitivity of 79%.
Diagnostic sensitivity of EBUS was 77% for stage 1 and 62% for stage 2 sarcoidosis, and increased according to number of stations sampled (1 station 66%, 2 stations 70%, ≥3 stations 92%).
Sensitivity from EUS-accessible nodes (Stations 7 and 4) was 72%, while this was 56% in EUS- inaccessible nodes (Stations 2, 10 and 11). If EUS-accessible nodes were present and sampled, additional sampling of EUS-inaccessible nodes did not further the diagnosis.
Conclusions In suspected sarcoidosis, the diagnostic yield of EBUS was 71%. Using additional bronchial biopsy techniques increased this by 8%. Mediastinal nodes, accessible by both EUS and EBUS, would appear to be the preferred site of sampling. However, EBUS allows sampling of nodes not accessible to EUS, which may be diagnostic if there is isolated hilar lymphadenopathy.