An unusual cause of recurrent spontaneous pneumothorax: the Mounier-Kuhn syndrome.

We present a case of 63-year-old man who was referred to the emergency department with a right-sided pneumothorax. He had a history of spontaneous pneumothorax for 2 times. The chest computed tomographic scan showed tracheobronchomegaly with an increase in the diameter of the trachea and right and left main bronchus. Fiberoptic bronchoscopy revealed enlarged trachea and both main bronchus with diverticulas. These findings are consistent with a diagnosis of Mounier-Kuhn syndrome. Mounier-Kuhn syndrome is a rare clinical and radiologic condition. It is characterized by a tracheal and bronchial dilation. Diagnosis is made by computed tomography and bronchoscopy. Mounier-Kuhn syndrome should be kept in mind in the differential diagnosis of recurrent spontaneous pneumothorax.