Granulomatous Hypophysitis with Meningitis and Hypopituitarism

We report an unusual case of granulomatous hypophysitis in which visual impairment, meningitis and hypopituitarism in a 76-year-old female were associated with radiological evidence of a pituitary mass. The sellar lesion was indistinguishable from pituitary tumor on neuroimaging studies, but the recovery of visual acuity and visual field abnormalities together with the improvement of pituitary function after steroid administration indicated that the mass lesion was due to an inflammatory disease of the pituitary gland. The pituitary tissue obtained by transsphenoidal hypophysectomy revealed granulomatous inflammatory cell infiltration with epithelioid cells and scattered multinucleated giant cells. Although a causal relationship with meningitis was not ascertained, possible exposure of the CSF space to the autoimmune inflammatory process of the pituitary gland was likely in view of the positive pituitary antibody reaction and radiological evidence of suprasellar extension. This entity should be considered when evaluating patients with a pituitary mass, hypopituitarism and meningitis. (Internal Medicine 31 : 1147-1150, 1992)