Endobronchial Ultrasonography Features in Tuberculous Mediastinal Lymphadenopathy

Area of Science:

• Pulmonology
• Infectious Diseases
• Radiology

Background:

• Mediastinal lymphadenopathy signifies intrathoracic pathology, with Tuberculous Mediastinal Lymphadenopathy (TML) being an early indicator of tuberculosis (TB) infection, particularly in developing nations.
• Underdiagnosis and limited diagnostic tools obscure the true incidence of TML, highlighting the critical need for prompt diagnosis to prevent fatal complications.
• Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a key diagnostic procedure, though its application faces limitations.

Purpose of the Study:

• To investigate the diagnostic utility of Endobronchial Ultrasound (EBUS) features in assessing Tuberculous Mediastinal Lymphadenopathy (TML).
• To identify specific EBUS characteristics associated with TML for improved diagnostic accuracy.

Main Methods:

• A cross-sectional study involving patients over 18 years old with suspected TML undergoing EBUS-TBNA.
• Systematic evaluation of mediastinal lymph nodes via EBUS, focusing on largest nodes for characteristic analysis.
• Analysis of aspirated samples for pathology, acid-fast bacilli, Mycobacterium tuberculosis (MTB) culture, and Xpert Ultra testing.

Main Results:

• Out of 100 recruited patients, 53 were diagnosed with TML.
• Significant associations were found between TML and lymph node characteristics: small short axis size (p<0.001), oval shape (p=0.034), indistinct margin (p<0.001), central hilum (p<0.001), internal echo (p<0.049), thin layer echogenicity (p=0.033), and nodal matting (p<0.001).
• Xpert Ultra demonstrated the highest sensitivity (71.7%) for TML diagnosis among the tested modalities.

Conclusions:

• Specific Endobronchial ultrasonographic features such as small size, round shape, indistinct margin, central hilum, internal echo, thin layer, and nodal matting are indicative of TML.
• These EBUS findings can guide clinicians towards a diagnosis of TML, facilitating timely treatment.
• The study underscores the importance of integrating EBUS imaging characteristics with microbiological tests for accurate TML diagnosis.