Endobronchial ultrasound-guided cautery-assisted transbronchial mediastinal cryobiopsy in the diagnosis of fibrosing mediastinitis secondary to atypical sarcoidosis: a case report

Background: Fibrosing mediastinitis (FM) secondary to atypical sarcoidosis (atypical presentation of sarcoidosis) is rarely reported at home and abroad. Its clinical manifestations represent a lack of specificity, and the initial diagnosis is frequently difficult. In particular, this case has multiple pulmonary nodules with mediastinal lymph node enlargement and bilateral pleural effusion, and pulmonary fibrosis still exists after treatment, which is inconsistent with any clinical stage of pulmonary sarcoidosis, further increasing the diagnostic difficulty. We retrospectively analyzed the clinical data of a case of FM secondary to atypical sarcoidosis diagnosed by endobronchial ultrasound-guided cautery-assisted transbronchial mediastinal cryobiopsy (EBUS-CA-TBMCB) in Chongqing University Fuling Hospital, to improve clinicians' attention to FM and understand that EBUS-CA-TBMCB remains an effective way of etiological diagnosis.