Utility of microbiological testing of thoracic lymph nodes sampled by endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) in patients with mediastinal lymphadenopathy

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) represents a minimally invasive technique to sample peribronchial and mediastinal lymph nodes for diagnosis of cancer, lymphoma, or sarcoidosis. However, the value of EBUS-TBNA in diagnosis of respiratory infections has not been well explored. Here, microbiologic testing data for EBUS-TBNA samples collected from 82 patients over a 30-month period were retrospectively reviewed. No organisms were identified on Gram, acid-fast, or fungal stains. Bacterial cultures were positive in 52% of samples; however, all but 1 culture were considered contaminants. Mycobacterial cultures yielded Mycobacterium avium-intracellulare not identified in a concurrent bronchoalveolar lavage sample in 1 patient. Fungal cultures were negative. Overall, routine microbiologic tests on EBUS-TBNA samples do not appear sufficiently sensitive to rule out infectious causes of adenopathy. High clinical suspicion for infection may require modification of sampling techniques or more sensitive detection methods.