Neuroepithelial cyst presenting as recurrent aseptic meningitis

A 41-year-old man had three episodes of acute aseptic meningitis from the age of thirty-six. With each episode he had severe occipital headache associated with a mononuclear pleocytosis and an increase in CSF protein. He had a neuroepithelial cyst originating from the choroid plexus of the right cerebellomedullary cistern. Spontaneous ruptures of the cyst probably caused recurrent chemical meningitis. A neuroepithelial cyst must be considered in the differential diagnosis of intracranial cystic tumors presenting with aseptic meningitis.