Pituitary apoplexy with sterile meningitis.

In 255 patients with evidence of a pituitary tumor, 7 patients presented with typical symptoms of meningitis, which all proved to be sterile. In these patients a pituitary adenoma was surgically verified in 4. In one patient the presence of acromegaly indicated a pituitary adenoma. In 2 patients an enlarged, empty sella was found, taken to reflect spontaneous disappearance of an adenoma. It is thought that the cause of the sterile meningeal reaction in the 7 patients was a spontaneous necrosis of the adenoma with expulsion of necrotic material into the suprasellar subarachnoid space. Although this sequence has been described before it has been considered to occur very rarely. Pituitary apoplexy as the underlying cause of meningitis should be suspected in patients with evidence of pituitary endocrine disturbances or lesion of structures adjacent to the fossa. The diagnosis may be established by computer tomography. Therapeutically, it may be of importance that the nature of the meningeal reaction is promptly recognized. Swift neurosurgical decompression of the sella and adequate hormonal substitution therapy may be essential.