Lymphocytic adenohypophysitis with sudden onset of diabetes insipidus in menopausal female--case report.

A rare case of a postmenopausal (60-year-old) female with lymphocytic adenohypophysitis manifesting as a sudden onset of diabetes insipidus is reported. Magnetic resonance imaging with gadolinium-diethylene-triaminepentaacetic acid enhancement showed a spherical lesion, approximately 1 cm in diameter, in the sella turcica and a thickened, deviated pituitary stalk. The abnormal tissue was totally removed. Histological examination showed marked infiltration of lymphocytes and plasma cells. Postoperatively, the pituitary stalk became normal. Preoperative differentiation of lymphocytic adenohypophysitis from pituitary adenoma is extremely difficult, and biopsy is essential.