[A case of granulomatous hypophysitis]

The patient was an unmarried, 25-year-old woman who presented herself with amenorrhea and lactation as her chief complaints. Radiography revealed a tumor in the sella turcica. Upon neurological examination at the time of admission, there were no abnormal findings affecting the field of vision or visual acuity, and no abnormalities were seen in the fundus oculi. In endocrinological tests, the basal plasma values of pituitary hormones were normal except for that of prolactin, which was 69.1 ng/ml. The preoperative diagnosis was nonfunctioning pituitary adenoma, and this neoplasm was resected by the transsphenoidal approach. Postoperative histological investigation showed vermiculous destruction of the anterior lobe of the pituitary gland, and also scattered lymph follicles accompanying infiltration by numerous lymphocytes and multinucleated foreign-body giant cells, and deposition of calcium. These findings, together with the epithelioid cells gathered around them, pointed to a diagnosis of granulomatous hypophysitis. The causes of granulomatous hypophysitis are known to include syphilis, tuberculosis, sarcoidosis, mycotic granuloma, and foreign-body granuloma due to the rupturing of a Rathke's cleft cyst, but no evidence of any of these was found in this patient. Another known source of inflammatory lesions in the hypophysis is lymphocytic hypophysitis, which resembles Hashimoto's autoimmune disease of the thyroid gland, and which is characterized both by the formation of lymph follicles and by extensive lymphocyte infiltration. In relation to the cause of granulomatous hypophysitis, thinking that it might possibly be an autoimmune disease, we conducted an immunological investigation, and also made a serological study of autoantibodies, but obtained no positive results.(ABSTRACT TRUNCATED AT 250 WORDS)