Endobronchial Ultrasonography Features in Tuberculous Mediastinal Lymphadenopathy

Mediastinal lymphadenopathy indicates an intrathoracic pathological process. Tuberculous mediastinal lymphadenopathy (TML) can be an early sign of tuberculosis infection, particularly in developing countries. Its incidence is often unclear due to underdiagnosis and limited access to diagnostic tools. Timely diagnosis is essential, as delayed treatment can result in severe complications. Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a reliable method for obtaining samples and establishing a diagnosis, although its use is constrained by various factors. This study aims to clarify the role of EBUS features in assessing TML.

This is a cross-sectional study that recruited ≥18 years old patients with suspected TML who underwent EBUS-TBNA. Mediastinal lymph nodes were systematically evaluated EBUS, with a focus on the largest nodes for further characteristic analysis. A TBNA was performed, and the retracted samples were assessed for pathology, acid-fast bacilli, Mycobacterium tuberculosis (MTB) culture, and Xpert Ultra examinations.

One hundred patients were recruited for the study. Fifty-three of these patients were ultimately diagnosed with TML. Significant associations were found between TML and several factors: short-axis size (p<0.001), oval-shaped lymph nodes (p=0.034), indistinct margins (p<0.001), central hilar presentation (p<0.001), internal echoes (p<0.049), thin layer echogenicity (p=0.033), and nodal matting (p<0.001). Among the diagnostic modalities, Xpert Ultra demonstrated the highest sensitivity for TML at 71.7%.

Endobronchial ultrasonographic features such as small size, round shape, indistinct margin, central hilar presentation, internal echo, thin layer echogenicity, and nodal matting are indicative of TML.