A pituitary abscess masquerading as recurrent hypernatremia and aseptic meningitis.

Pituitary abscess is a rare condition. In the setting of multiple surgical interventions, the risk of its development increases. A 49-year-old man presented with episodes of altered mental status. He had two surgeries for a recurrent suprasellar arachnoid cyst. The second surgery was complicated by a persistent cerebrospinal fluid (CSF) leak that required two repairs following which he developed panhypopituitarism and central diabetes insipidus. Twelve months after his last surgery he was diagnosed with aseptic meningitis. This was followed by recurrent hospitalisations for severe hypernatremia blamed on poor medication compliance. He was subsequently hospitalised for the evaluation of a febrile illness. Brain MRI showed ventriculitis and enhancement of the sella. Exploratory surgery revealed a purulent collection in the sella and a mucosal graft which had been used to repair the CSF leak. After drainage of pus and replacement of the graft he recovered completely but requiring life-long hormonal replacement.