The diagnostic efficacy of EBUS-TBNA in tuberculous lymphadenitis

Aim: Endobronchial ultrasound (EBUS) transbronchial needle aspiration (TBNA) is an important diagnostic procedure for the interrogation of mediastinal lymph nodes. In this study, we aimed to evaluate the diagnostic contribution of EBUS-TBNA in the evaluation of intrathoracic tuberculous lymphadenitis. Methods: This retrospective study included 527 patients who had undergone EBUS-TBNA between December 2012 and December 2014. Final diagnosis of 527 patients and complications of the procedure were evaluated. Results from the procedures were recorded, including microscopy for acid-fast bacilli (AFB), cytology, mycobacterial cultures, standard bacterial cultures and the results of nucleic acid amplification techniques (NAAT). Final diagnosis of tuberculous lymphadenitis (TBLA) were evaluated and the sensitivity, negative predictive value (NPV) of EBUS-TBNA for TBLA were calculated. Results: Tuberculous was diagnosed in 28 patients (28/527, 5.2%). EBUS-TBNA diagnostic in 23 (82.1%) patients. In 5 TBLA patients, EBUS-TBNA was not able to confirm a diagnosis and additional procedures were required. Sensitivity of EBUS-TBNA for all microbiological tests was 53.5% in TBLA. The sensitivity for a composite microbiological and clinicopathological diagnosis of EBUS-TBNA was found 82.1 %. Sensitivity of NAAT was 14.8%. The negative predictive value (NPV) for microbiologic and composite clinicopathological investigation diagnosis was 97.8% and 99% respectively. Conclusions: EBUS-TBNA is a safe and effective procedure in the assessment of patients with TBLA. When microbiological tests and histological results are combined with high clinical suspicion, EBUS-TBNA demonstrates good diagnostic accuracy and NPV for the diagnosis of TBLA.