Diagnostic yield and safety of transbronchial cryobiopsy in sarcoidosis

Introduction: Transbronchial lung cryobiopsy (TBLC) is an endoscopic technique proven to be useful in diagnostic approach to interstitial lung disease (ILD), but its role in sarcoidosis is not fully established. The aim of the present study was to assess the diagnostic yield of TBLC in sarcoidosis and its safety profile. Methods: Retrospective analysis of patients, evaluated in a tertiary hospital ILD outpatient clinic, who underwent TBLC in the diagnostic work-up. TBLC was performed in accordance with the 2018 expert statement from the Cryobiopsy Working Group. Results: 32 patients were included (mean +/- SD age 47.7 +/- 12.6 years, 59.4% male) and divided into three groups: highly likely sarcoidosis (n=21), possible sarcoidosis (n=6) and unlikely sarcoidosis (n=5). A mean of 2.8 +/- 0.8 TBLCs were performed. The definitive diagnosis was established by TBLC in 20 out of 27 patients with suspected sarcoidosis. Two patients were diagnosed with sarcoidosis by other methods performed afterwards. TBLC leaded to other diagnosis as well, such as fungal infection (n=1), hypersensitivity pneumonitis (n=1) and silicosis (n=3), making the diagnostic yield for suspected sarcoidosis of TBLC of 92.6%. TBLC was also able to show compatible histological features in five patients whom sarcoidosis was not previously considered. The complications reported overall were pneumothorax in five (15.6%) patients and moderate bleeding in one (3.1%) case. Conclusion: In this cohort, TBLC was a safe, reliable and useful procedure in sarcoidosis diagnosis. These results suggest that TBLC can be used successfully in those cases where a definitive diagnosis could not be reached with the usual and less-invasive diagnostic tools.