EBUS in pulmonary sarcoidosis: What to expect?

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.

TBLC is a safe procedure with a high diagnostic yield in patients with a prior suspicion of sarcoidosis. Moreover, it can diagnose atypical cases in which previous methods are inconclusive.http://bit.ly/2KWJxLG

Role of Bronchoscopic Techniques in the Diagnosis of Thoracic Sarcoidosis

The diagnosis of sarcoidosis relies on clinical and radiological presentation, evidence of non-caseating granulomas in histopathology and exclusion of alternative causes of granulomatous inflammation. Currently, a proper diagnosis, with a high level of confidence, is considered as key to the appropriate diagnosis and management of the disease. In this sense, this review aims to provide a brief overview on the role of bronchoscopy in the diagnosis of thoracic sarcoidosis, incorporating newer techniques to establish, including endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA), endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA), transesophageal ultrasound-guided needle aspiration with the use of an echo bronchoscope (EUS-B-FNA) and transbronchial lung cryobiopsy (TBLC). Most of the literature reports the diagnostic superiority of endosonographic techniques, such as EBUS-TBNA alone or in combination with EUS-FNA, over conventional bronchoscopic modalities in diagnosing Scadding stages I and II of the disease. Moreover, TBLC may be considered a useful and safe diagnostic tool for thoracic sarcoidosis, overcoming some limitations of transbronchial lung biopsy (TBLB), avoiding more invasive modalities and being complementary to endosonographic procedures such as EBUS-TBNA.