Idiopathic giant-cell granulomatous hypophysitis mimicking acute meningitis

A 32-year-old woman presented with severe headache, photophobia, fever, nausea, vomiting, and worsening vision. She had also noted several months of amenorrhea. She was febrile to 38.9 degrees C. Laboratory evaluation revealed a markedly elevated erythrocyte sedimentation rate. Lumbar puncture revealed a cerebrospinal fluid lymphocytic pleocytosis and an elevated protein level. Endocrine studies revealed evidence of panhypopituitarism without diabetes insipidus. A magnetic resonance imaging study showed a 2-cm pituitary mass with optic chiasmal compression. The patient had a trans-sphenoidal resection of the mass. Pathology revealed multinucleated giant cells in necrotic debris, but no evidence of pituitary tumor. Studies looking for evidence of systemic granulomatous disease were negative. The patient was considered to have idiopathic giant-cell granulomatous hypophysitis. After surgery, the patient's vision improved and hormone replacement therapy was initiated. This case illustrates that idiopathic giant-cell granulomatous hypophysitis should be considered in the differential diagnosis of a patient presenting with a pituitary mass, hypopituitarism, and meningitis-like symptoms.