Clinical usefulness of routine AFB culture and MTB PCR of EBUS‐TBNA needle rinse fluid

ABSTRACT Background and objective We evaluated the usefulness of acid‐fast bacilli (AFB) culture and Mycobacterium tuberculosis (MTB) polymerase chain reaction (PCR) of endobronchial ultrasound‐guided transbronchial needle aspiration (EBUS‐TBNA) needle rinse fluid for diagnosing tuberculous lymphadenitis. Methods EBUS‐TBNA needle rinse fluid was routinely used for AFB culture and MTB PCR. The patients were categorized according to the pre‐procedural diagnosis (Group A, suspected/histology‐confirmed lung cancer; Group B, extrapulmonary malignancy; and Group C, other benign diseases). Results Of the 4672 subjects, 104 (2.2%) were diagnosed with tuberculous lymphadenitis; 1.0%, 4.6% and 12.7% of Group A, B and C, respectively. Tuberculous lymphadenitis was diagnosed in 0.2%, 1.0% and 4.5% Group A, B and C patients, respectively, by histopathology. On addition of AFB culture to histopathology, tuberculous lymphadenitis was diagnosed in 1.0%, 4.4% and 10.3% of Group A, B and C patients, respectively (P