From Diagnosis to Emergency: Mediastinal Abscess After Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration in a Patient With Sarcoidosis.

Sarcoidosis is a systemic granulomatous disease of unknown etiology, primarily affecting the lungs and the lymphatic system. Its diagnosis is challenging, and in many cases, it requires histopathological confirmation through the identification of non-caseating granulomas. The presented case illustrates its diagnostic complexity and highlights a rare, delayed complication associated with endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA). The patient developed a mediastinal abscess, a serious and uncommon post-procedural event, which likely resulted from microperforation of the bronchial wall during the aspiration. Symptoms developed several days after the procedure, with fever, chest pain, and signs of mediastinal infection. This case emphasizes the need for heightened clinical awareness and careful monitoring following EBUS-TBNA.