A pitfall in the diagnosis of giant bronchogenic cyst presented as loculated pleural effusion.

Being considered as an uncommon congenital anomaly, pulmonary bronchogenic cyst requires surgical treatment due to its rarity and mortality especially in complicated forms. In the present paper, we are presenting a case report of a giant pulmonary bronchogenic cyst (18 cm × 15 cm × 10 cm) misdiagnosed with loculated pleural effusion. Because of unsuccessful treatment of tube thoracostomy, the patient was scheduled for left thoracotomy. Later giant pulmonary cyst was removed completely without any complications. Histopathology studies revealed a giant bronchogenic cyst with abscess formation.