Diagnostic Factors Associated with Sarcoidosis in Patients Referred for EBUS-TBNA Due to Mediastinal Lymphadenopathy

Sarcoidosis is a multisystem granulomatous disease of unknown aetiology that frequently presents with mediastinal lymphadenopathy and often requires invasive diagnostic procedures. Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is widely used in this setting; however, a definitive diagnosis cannot always be established at first attempt. This study aimed to identify clinical, laboratory, and radiological factors associated with a definitive diagnosis of sarcoidosis in patients referred for EBUS-TBNA. A retrospective analysis was performed including patients undergoing first-time ever EBUS-TBNA for mediastinal lymphadenopathy over a 12-month period. Demographic data, clinical features suggestive of sarcoidosis, chest computed tomography findings, and white blood cell count, were analysed, and definitive diagnoses were established based on cytological results and available follow-up data. Younger age (≤55 years), female sex, the absence of a pulmonary mass >10 mm on imaging, normal white blood cell count, and the presence of clinical features typical of sarcoidosis were significantly associated with a definitive diagnosis of sarcoidosis. Based on these variables, two point-based diagnostic scoring models were developed, demonstrating clinically relevant discriminatory performance. Readily available pre-procedural clinical and radiological factors may assist in estimating the probability of sarcoidosis in patients undergoing EBUS-TBNA for mediastinal lymphadenopathy and may support risk stratification and clinical decision-making.