CSF hydrothorax: An unusual cause of pleural effusion.

A 20-year-old male with hydrocephalus managed with a ventriculoperitoneal shunt (VP) was diagnosed with a cerebrospinal fluid (CSF) pleural effusion. Imaging studies revealed an intrathoracic course of a disconnected VP shunt. Physicians should consider CSF effusion in their differential diagnosis in patients with a VP shunt and an unexplained pleural effusion.