Xanthomatous Hypophysitis Presenting with Diabetes Insipidus Completely Cured Through Transsphenoidal Surgery: Case Report and Literature Review.

BACKGROUND: Xanthomatous hypophysitis (XH) is extremely rare. Only 27 cases have been reported in the literature. No XH patient presenting with diabetes insipidus (DI) has been completely cured through surgery. Here, we describe the first XH case of a DI patient whose pituitary function was normalized postoperatively, without hormone replacement therapy.

CASE DESCRIPTION: A 41-year-old woman suffered from polydipsia, DI, headache, and breast discharge. Laboratory investigation revealed hyperprolactinemia. Pituitary magnetic resonance imaging showed a 2.0-cm × 1.4-cm × 1.6-cm lesion that demonstrated heterogeneous intensity on T1-weighted imaging and peripheral ring enhancement following contrast; the lesion was totally removed through transsphenoidal surgery. Histopathologic and immunohistochemical examinations confirmed the diagnosis of XH. At the 4- and 15-month follow-up visits, all pituitary-related hormones were normal, and the patient was not taking medication. A repeat pituitary magnetic resonance imaging showed no evidence of recurrence.

CONCLUSIONS: To the best of our knowledge, this case is the first documented occurrence of XH with DI completely cured through surgery. If XH is suspected, total surgical resection of the lesion is recommended and normal pituitary tissue should be carefully protected intraoperatively.