Role of EBUS-TBNA in Non-Neoplastic Mediastinal Lymphadenopathy: Review of Literature

Role of Bronchoscopy in Diagnosis of Sarcoidosis

Sarcoidosis is a multisystem inflammatory disorder with unclear etiology and can often pose a diagnostic challenge. A tissue diagnosis is often necessary to illustrate the non-caseating granulomas on histopathology. This review aims to synthesize current evidence related to tissue diagnosis of sarcoidosis using various bronchoscopic techniques. We start by discussing standard bronchoscopic techniques which have remained the cornerstone of diagnostic workup such as bronchoalveolar lavage (BAL), endobronchial biopsy (EBB), conventional transbronchial needle aspiration (cTBNA) and transbronchial lung biopsy (TBLB) followed by newer modalities that incorporate real-time image guidance using endobronchial and endoscopic ultrasound. Although BAL, EBB, and TBLB have been employed as a diagnostic tool for several decades, their sensitivity and diagnostic yield is inferior to ultrasound-based endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) and endoscopic ultrasound-guided fine needle aspiration (EUS-FNA). More recently, convincing evidence has also emerged to support the diagnostic accuracy and tissue yield of transbronchial lung cryobiopsy which will also be discussed in this review. These advances in bronchoscopic equipment and techniques over the last 2 decades have made it possible to obtain tissue samples using minimally invasive techniques thus avoiding invasive open lung biopsy and the risks that inherently follow. Up-to-date knowledge of these modalities is imperative for ensuring evidence-based medicine and improving patient-centric outcomes.

Using Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration for the Diagnosis and Treatment of a Mediastinal Mass With Eccentric Calcifications: A Case Report

Mediastinal masses present a diagnostic challenge due to their similar imaging characteristics, making distinguishing between noninfectious and infectious processes or malignancies difficult. A mediastinal abscess can result in severe life-threatening infections if left untreated. Traditional treatment approaches involve surgical debridement and drainage; however, emerging endobronchial techniques, such as endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA), offer a less-invasive means of diagnosing and managing abscesses. Herein, we describe a case of a young male patient who exhibited nonspecific symptoms, including pleuritic chest pain, shortness of breath, and fever. Imaging revealed a mediastinal mass with granuloma formation. EBUS-TBNA successfully drained the abscess, and microbiology analysis confirmed the growth of Streptococcus intermedius. Subsequently, his symptoms resolved, and follow-up imaging demonstrated the resolution of the mass and associated calcifications. Further research is warranted to assess the role of EBUS-TBNA in benign mediastinal masses with granuloma formation.

Is the diagnostic yield of mediastinal lymph node cryobiopsy (cryoEBUS) better for diagnosing mediastinal node involvement compared to endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA)? A systematic review

INTRODUCTION

New tools such as cryobiopsy of mediastinal lymph nodes (cryoEBUS) have been described to improve the diagnostic usefulness of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA). The literature suggests that this novel procedure could be associated with greater diagnostic usefulness than conventional EBUS-TBNA.

METHODS

To develop a systematic analysis and meta-analysis on the diagnostic diagnostic yield and safety of cryobiopsy of hilar and mediastinal adenopathies compared to EBUS-TBNA.

RESULTS

Seven studies that had included a total of 555 patients were considered in this review, with 365 (65.7%) of these patients having an etiology of malignant lymph node involvement. The overall diagnostic usefulness of cryoEBUS was higher compared to EBUS-TBNA (92% vs. 80%). However, when the results were analysed according to the specific aetiologies of the adenopathies, cryoEBUS was especially useful in cases of lymphomas or non-pulmonary carcinomas (83% vs. 42%) and in cases that were benign (87% vs. 60.1%), with no significant differences being found in specific cases of lung cancer. For lymphoma, cryoEBUS was diagnostic in 87% of cases compared to 12% for EBUS-TBNA and in addition, also allowed the characterisation of every lymphoma subtype. Genetic studies and immunohistochemical determination of PD-L1 was possible in almost all (97%) of the samples obtained by cryoEBUS, while this was only possible in 79% of those obtained by EBUS-TBNA. The most frequent complication was light bleeding, which was described in up to 85% of cases in some series.

CONCLUSION

CryoEBUS could represent a promising technique in the diagnostic algorithm used for mediastinal and hilar involvement. Although cryoEBUS did not significantly improve the diagnosis of lung cancer compared to EBUS-TBNA, the results were significantly better in patients with benign pathologies and other tumour types, including lymphomas. In addition, it seems that the samples obtained by cryoEBUS better defined the histological subtypes of lymphoma and allowed complete molecular characterisation in cases of lung cancer. The technique has proven to be safe and no serious complications were described after the procedure.

Real time endobronchial ultrasound transbronchial needle aspiration for the diagnosis of tuberculous intrathoracic lymphadenopathy: Saudi Arabian Western region experience

OBJECTIVES

To assess the utility of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) for presumptive tuberculosis (TB) patients with intrathoracic enlarged lymph nodes in a country with low to moderate TB incidence.

METHODS

Thirty-one patients with clinical features of TB and intrathoracic lymphadenopathy, who had EBUS-TBNA sampling and final confirmation of intrathoracic TB lymphadenopathy, were retrospectively reviewed over an 8-year period. Routine clinical and laboratory evaluations including computerized tomography scans were performed before the EBUS-TBNA. Sociodemographic characteristics, clinical profile, pathological, and microbiological findings were collected.

RESULTS

The EBUS-TBNA confirmed TB diagnosis in 26 (83.9%) subjects with a consistent pathological finding or positive culture of Mycobacterium tuberculosis. Pathological analysis had findings consistent with TB in 25 (80.6%) patients. Culture of the EBUS-TBNA sample was positive for Mycobacterium tuberculosis in 12 (38.7%) patients. Other supportive investigations like purified protein derivative (PPD) skin test was positive in 28 (90.3%) participants. Overall, the sensitivity of the EBUS-TBNA alone was 83.9%. No complications were recorded during the procedure. The EBUS-TBNA aspirate culture positivity was significantly related to having a larger size lymph node (p=0.048) only, while PPD positivity was significantly related to baseline and clinical features of the participants.

CONCLUSION

The EBUS-TBNA demonstrated effective utility and safety in the evaluation and diagnosis of intrathoracic TB lymphadenopathy among individuals with compatible symptoms in a country with low-moderate TB-incidence.