A case of bronchogenic cyst mimicking foreign body aspiration.

Bronchogenic cysts (BCs) can be life threatening if they compress vital structures in infants and small children. In particular, subcarinal cysts can be life-threatening and compromise the airways. In infants, the initial presentation may be respiratory distress. We report a case of mediastinal cystic mass compressing the main left bronchus. The case was an 18-month-old boy who had been admitted with acute respiratory distress. Chest x-ray showed overdistension of the left lung and a mediastinal shift. Foreign body aspiration was diagnosed. Magnetic resonance imaging was performed, which has shown a mediastinal cystic mass; therefore, the patient underwent thoracotomy. Surgical intervention revealed a subcarinal extrapulmonary BC that compresses the left main bronchus. The diagnosis of BC was confirmed with pathological investigation. In this report, we present a case of BC with the emphasis on the differential diagnosis with foreign body aspiration.