Advantages and drawbacks associated with the use of endosonography in sarcoidosis

ABSTRACT

Introduction

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a real-time, minimally invasive procedure for sampling intrathoracic lymph nodes. Herein, we discuss EBUS-guided procedures, their benefits, and drawbacks in diagnosing sarcoidosis.

Areas covered

We first describe the utility of various endosonographic imaging techniques like B-mode, elastography, and doppler imaging. We then review the diagnostic yield and safety of EBUS-TBNA and compare it with the other available diagnostic modalities. Subsequently, we discuss the technical aspects of EBUS-TBNA influencing the diagnostic yield. Recent advances in EBUS-guided diagnostics like EBUS-guided intranodal forceps biopsy (EBUS-IFB) and EBUS-guided transbronchial mediastinal cryobiopsy (EBMC) are reviewed. Finally, we summarize the advantages and disadvantages associated with EBUS-TBNA in sarcoidosis and provide an expert opinion on the optimal use of this procedure in patients with suspected sarcoidosis.

Expert opinion

EBUS-TBNA is a minimally invasive, safe procedure with a good diagnostic yield, and should be the preferred diagnostic modality for sampling intrathoracic lymph nodes in patients with suspected sarcoidosis. For optimal diagnostic yield, EBUS-TBNA should be combined with endobronchial biopsy (EBB) and transbronchial lung biopsy (TBLB). Newer endosonographic techniques like EBUS-IFB and EBMC might obviate the need for EBB and TBLB due to their superior diagnostic yield.

KEYWORDS:

• Sarcoidosis
• EBUS
• endosonography
• cryobiopsy
• tuberculosis
• mediastinal lymphadenopathy

Article highlights

• Sarcoidosis is a chronic granulomatous disorder commonly associated with intrathoracic lymphadenopathy.

• Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is an endosonographic diagnostic procedure that allows imaging and sampling of intrathoracic lymph nodes under real-time ultrasound guidance.

• Most of the lymph node characteristics on endosonographic imaging do not adequately differentiate sarcoidosis from other diagnoses. However, the presence of coagulation necrosis sign along with granulomatous inflammation is strongly suggestive of tuberculosis rather than sarcoidosis.

• The advantages of EBUS-TBNA include a good diagnostic yield in sarcoidosis (about 80%), minimal invasiveness, and the rarity of complications. The drawbacks of EBUS-TBNA include the limited availability in developing countries and a suboptimal diagnostic yield in sarcoidosis when used as a standalone procedure.

• The diagnostic yield of EBUS-TBNA approaches 95% in sarcoidosis when EBUS-TBNA is combined with other techniques like endobronchial biopsy (EBB), transbronchial lung biopsy (TBLB), EBUS-guided intranodal forceps biopsy (EBUS-IFB), or EBUS-guided transbronchial mediastinal cryobiopsy (EBMC). Emerging evidence indicates that EBUS-IFB and EBMC may potentially obviate the need for other procedures like EBB and TBLB.

Declaration of interests

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This paper was not funded.