Role of EBUS-TBNA in the Diagnosis of Tuberculosis and Sarcoidosis.

Endobronchial ultrasound (EBUS)-guided transbronchial needle aspiration (TBNA) has diagnostic accuracy and negative predictive value for the diagnosis of mediastinal tubercular lymphadenitis, especially when culture and cytological diagnosis is combined with high clinical suspicion. Both sarcoidosis and tuberculosis (TB) demonstrate granulomatous inflammation on cytology. Diagnosis of sarcoidosis in regions with a high burden of TB is challenging. We conducted a prospective study in 179 cases of suspected granulomatous pathology in mediastinal lymphadenopathy cases to evaluate the role of EBUS-TBNA in diagnosis of sarcoidosis and TB. It was found that extensive caseous necrosis, acid-fast bacilli positivity on Ziehl-Neelsen staining, and/or microbiological culture positivity have high positive predictive value for the diagnosis of TB.