Background: Inflammation of the pituitary gland can occur in a variety of primary or secondary disorders. Idiopathic granulomatous hypophysitis is a rare inflammatory disease of the pituitary gland that can closely mimic a pituitary adenoma clinicoradiologically. Most authorities agree on minimally invasive transsphenoidal surgery as the mainstay in diagnosis and treatment of this disorder. There is still some controversy regarding pure medical management of idiopathic granulomatous hypophysitis in the literature.
Case presentation: A 47-year-old Iranian woman of Azeri ethnicity with a history of benign breast cysts with a chief complaint of galactorrhea presented to our endocrinology clinic. Her past medical history was negative for any menstrual irregularities, hirsutism, visual complaints, diplopia, polyuria and polydipsia or seizures. She was taking 100 mcg of levothyroxine daily. Her familial history and physical examination were unremarkable. Her initial laboratory work-up revealed hyperprolactinemia (82.4 ng/mL) with otherwise normal pituitary axes. Brain magnetic resonance imaging showed a pituitary macroadenoma for which she was treated with 0.5 mg of cabergoline weekly. Although her serum prolactin level dropped to 1.7 ng/mL and her galactorrhea was resolved, she continued to complain of headaches and nausea. Repeated imaging showed no decrease in size of the macroadenoma. Therefore, she underwent transsphenoidal surgery of the macroadenoma which was reported as chronic granulomatous hypophysitis by expert pathologists. Tuberculosis, sarcoidosis, Wegener's granulomatosis, Langerhans cell histiocytosis, and syphilis were ruled out by appropriate tests and she was diagnosed as having idiopathic granulomatous hypophysitis. Fortunately, her condition was not complicated by hypopituitarism and she was symptom free 9 months after transsphenoidal surgery.
Conclusions: Idiopathic granulomatous hypophysitis, a rare inflammatory disease of the pituitary gland, is a diagnosis of exclusion for which both medical and surgical management are reported in the literature. We present a case of idiopathic granulomatous hypophysitis who was symptom free with no complications of hypopituitarism following its transsphenoidal resection after 9 months of follow-up.
Keywords: Autoimmune hypophysitis; Galactorrhea; Idiopathic granulomatous hypophysitis; Pituitary gland; Transsphenoidal surgery.