Endobronchial ultrasound-guided transbronchial needle aspiration in diagnosing intrathoracic tuberculosis

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a minimally invasive procedure that has enabled mediastinal and hilar lymph node assessment with a high sensitivity, but its role in the diagnosis of intrathoracic tuberculosis (TB) has not been established.

We prospectively studied 59 patients suspected of having TB with thoracic lymph node lesions or intrapulmonary lesions accessible by EBUS-TBNA at a clinical center for thoracic medicine from January 2010 to December 2011. Bronchoscopic findings, EBUS-TBNA procedures, pathologic findings, and microbiologic results were recorded.

Of 59 eligible patients, 41 patients had TB, 5 had lung cancer, 7 had inflammation, and 6 had sarcoidosis. Sensitivity was 85%, specificity was 100%, positive and negative predictive values were 100% and 75%, respectively, and accuracy was 90% by EBUS-TBNA for TB. Pathologic findings were consistent with TB in 80% of patients (33 of 41), and in 27% (11 of 41) the smear was positive. A total of 37 patients with TB had cultures, of whom 17 (46%) were positive. There were 80 mediastinal and hilar lymph nodes and 5 intrapulmonary lesions that were biopsied in the 41 patients with TB. Multivariate logistic regression revealed that short-axis diameter was an independent risk factor associated with positive pathology, smear, and culture (p < 0.05). Additionally, pathology showing necrosis was an independent risk factor associated with a positive culture.

Endobronchial ultrasound-guided transbronchial needle aspiration has a high diagnostic yield in the investigation of suspected intrathoracic TB by means of aspiration of intrathoracic lymph nodes and tracheobronchial wall-adjacent lung lesions.