Late-appearing diaphragmatic hernia following resolution of right pleural effusion

A case of late-appearing congenital diaphragmatic hernia in a premature infant with previously normal chest X-ray is reported. Pleural effusion accumulation and resolution preceded herniation of the liver to the right hemithorax and development of respiratory symptoms. Chest X-ray, ultrasound and computed tomography of the chest were useful in establishing the correct diagnosis. Pleural effusion without obvious cause should alert the paediatrician to the possibility of this rare condition.