A Case of Lymphocytic Hypophysitis Masked as Pituitary Apoplexy

Program: Abstracts - Orals, Featured Poster Presentations, and Posters
Session: SUN 163-194-Pituitary Disorders & Case Reports
Basic/Clinical
Sunday, June 16, 2013: 1:45 PM-3:45 PM
Expo Halls ABC (Moscone Center)

Poster Board SUN-172
Aren Skolnick*1, Mark Eisenberg2, B. Todd Schaeffer2 and Yael Harris3
1North Shore-LIJ Health Sys, Great Neck, NY, 2North Shore-LIJ Health System, Manhasset, NY, 3North Shore University Hospital/LIJHS, Great Neck, NY
A Case of Lymphocytic Hypophysitis Masked as Pituitary Apoplexy

Background

Lymphocytic hypophysitis is caused by lymphocytic infiltration of the anterior pituitary gland leading to enlargement, and frequently fibrosis and atrophy. While generally a peripartum phenomenon, it can occur in men and postmenopausal women. Evidence supports an autoimmune etiology and co-existing autoimmune conditions are common.  Hormone deficiencies usually involve ACTH and TSH with rare preservation of pituitary function. We present a case of lymphocytic hypophysitis initially diagnosed as pituitary apoplexy in a postmenopausal woman without clinically significant hormonal deficits.

Case:

A 51-year-old woman presented to her internist with 6 months of headaches and fatigue. Blood tests including thyroid function tests were normal. CT of the head was nondiagnostic; MRI showed a  1.3x1.5x1.4 cm sellar mass with posterior expansion and partial effacement of the suprasellar cisterns. Endocrine evaluation revealed prolactin 14ng/ml, GH 0.08ng/ml, ACTH 28.2 pg/ml, IGF-1 81ng/ml. LH 11.3 mIu/ml and FSH  18.3 mIU/ml were inappropriate for a postmenopausal female. Visual fields were fully intact. The patient was referred for neurosurgical evaluation and recommended 6 month follow-up MRI. She developed a severe headache on the day of the MRI, which showed enlargement of the adenoma to 2.5x1.5x1.6cm with invasion into the cavernous sinus and T1 hyperintensity with possible apoplexy.  AM cortisol was 16ug/dl, TSH 1.61, Free T4 1.2, ESR 82 mm/hr, Prolactin 23.5 ng/ml. Worsening headaches prompted transphenoidal surgery with intraoperative biopsy revealing adenohypophyseal tissue with lymphoplasmacytic infiltration, occasional polymorphonuclear leukocytes, rare eosinophils consistent with lymphocytic hypophysitis. The area was drained and the remainder of the pituitary was left intact. The patient’s headaches improved, with no further hormone dysfunction.

Conclusion:

Lymphocytic hypophysitis is an uncommon disorder characterized by inflammation and eventual destruction of the anterior pituitary. Varying degrees of hormone dysfunction produce a spectrum of clinical symptoms that can mimic pituitary adenoma or even apoplexy.  This case demonstrates that consideration of lymphocytic hypophysitis in the differential diagnosis can defer complete surgical resection of the pituitary and potentially spare long-term pituitary function. The elevated ESR, in this case, likely reflected pituitary inflammation, and may have utility as a marker of treatment-response.

Nothing to Disclose: AS, ME, BTS, YH

*Please take note of The Endocrine Society's News Embargo Policy at http://www.endo-society.org/endo2013/media.cfm