Bronchogenic Cyst Rupture and Pneumonia after Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration: A Case Report
A 54-year-old female patient was referred to our hospital with abnormal chest radiography. She was asymptomatic except for sputum, not purulent, and had a normal physical examination. Contrast-enhanced computed tomography (CT) of the chest revealed a 69-mm-sized, well-defined, homogeneous, and non-enhancing mass in the retrobronchial region of the bronchus intermedius (). For further diagnostic evaluation, EBUS was performed using a 7.5-MHz-frequency convex probe bronchoscope (CP-EBUS, BF-UC260F-OL8; Olympus, Tokyo, Japan). A dedicated ultrasound scanner (EU-C2000; Olympus) was used as the image processor. On flexible bronchoscopic examination, there was no endobronchial lesion in the trachea, left or right main bronchus, or bronchus intermedius. On EBUS, an approximately 40-mm-sized low-echogenic mass was seen on the posterior side of the right main bronchus (). Although the ultrasound characteristics were suspicious for a cystic lesion, TBNA was performed for histological confirmation of the mass lesion.\nA dedicated 22-gauge needle (NA-201SX-4022; Olympus) was used to puncture and aspirate the lesion under direct visual guidance. Serous fluid was aspirated by EBUS-TBNA. Cytological examination identified an acellular smear with negative microbiological cultures. The patient did not experience any immediate complication such as hemorrhage, pneumothorax, or pneumomediastium from the procedure. The EBUS images correlated with the TBNA aspirate findings, and the patient was diagnosed with bronchogenic cysts.\nOne week after EBUS-TBNA, the patient reported fever, cough, and purulent sputum. A CT scan of the chest revealed a cavitary consolidation communicating with an adjacent bronchogenic cyst that replaced the air space (). With a suspected diagnosis of pneumonia from bronchogenic cyst rupture, the patient was started on empirical oral antibiotics. A 3-week course of amoxicillin/clavulanate was prescribed. During the weeks following the event, the size of the consolidation in the right upper lung zone slowly decreased on chest radiography, and the patient was free from symptoms. At 4-month follow-up, chest CT revealed interval improvement of combined pneumonia over the bronchogenic cyst in the right upper lobe (). She had no evidence of ongoing infection.