Mediastinal Tuberculous Lymphadenitis Diagnosed by Tissue Culture with Endobronchial Ultrasound-guided Transbronchial Needle Aspiration

In this study, a 60-year-old man with psoriatic arthritis receiving adalimumab was referred for abnormalities found from the results of his chest radiograph and computed tomography (CT) scan. He did not have a fever, and the blood tests showed no remarkable findings. Nonenhanced CT revealed mediastinal lymphadenopathy. We performed a bronchoscopy, specifically endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA), of the subcarinal lymph node (#7). The tissue cultures obtained by EBUS-TBNA were positive for Mycobacterium tuberculosis (M.Tb). The tissue M.Tb polymerase chain reaction (TB-PCR) test was also positive, but the culture and the TB-PCR of the bronchial wash fluid and rinse fluids of the brush and the needle of EBUS-TBNA were negative for M.Tb. A mediastinal tuberculous lymphadenitis (TBL) diagnosis was made, and the patient was prescribed antituberculosis drugs for 9 months. After the completion of the antituberculosis treatment, the size of the mediastinal lymph nodes reduced. In conclusion, performing EBUS-TBNA and analyzing the culture and the TB-PCR of the tissue obtained by EBUS-TBNA to test for susceptibility to M.Tb may aid with TBL diagnosis and treatment.