ODP331 Management and Long Term Outcomes in a Patient with Pituitary Apoplexy in Pregnancy

BACKGROUND: Pituitary apoplexy is caused by hemorrhage or infarction of the pituitary gland. This diagnosis is rare in pregnancy, with little data to guide management in this population. CASE: A 30-year-old previously healthy pregnant female G4P3002 at 31 weeks gestation, presented with three days of severe headaches, dizziness, polyuria, polydipsia, and photophobia without vision loss. Her last pregnancy two years prior was uncomplicated. Pituitary MRI showed a 1.5 cm lesion with internal blood products, possibly indicating recent hemorrhage within an adenoma or cyst. The pituitary gland extended into the suprasellar cistern without compressing the optic chiasm. She was empirically started on stress dose steroids. Labs showed an ACTH of 32.9 pg/mL [9. 0-50. 0], cortisol 27.13 mcg/dL [3. 09-22.40], TSH 1.404 uIU/mL [0.550-4.780], with free T4 0.94 ng/dL [0.93-1.76] and total T4 of 11. 0 mcg/dL [4.5-10.9]. Glucocorticoids were continued given the inability to verify adrenal insufficiency after steroid initiation. Central hypothyroidism was diagnosed based on total T4 being less than 1.5 times the upper limit of the pre-pregnancy normal range, and she was started on levothyroxine. Prolactin was 93. 0 ng/mL [9.7-208.5] without hook effect on dilutional testing; this value was considered lower than expected for the third trimester. IGF-1 was normal at 296 ng/mL [117-329]. FSH was <0.3 mIU/mL [<0.3], LH <0.7 mIU/mL [<0.1-1.5], and estradiol >4000 pg/mL [reference range unavailable], all normal values for pregnancy. She had a normal serum sodium, however had polyuria at 266 mL/hour during a six hour water restriction test, with persistently dilute urine studies. Urine output and concentration improved after giving desmopressin. She was diagnosed with partial central diabetes insipidus and started on maintenance desmopressin. Per her obstetric team's recommendation, she underwent an uncomplicated Caesarean section at 38 weeks and was able to breastfeed shortly after delivery . Due to refractory headaches, 8 weeks after delivery she underwent transsphenoidal resection of an intrasellar cystic lesion with old blood products. No adenoma was identified. She was able to taper off hydrocortisone, desmopressin, and levothyroxine over one year after surgery. Follow up FSH, LH, estradiol, and prolactin levels normalized, and she resumed regular menses. Annual MRI's over five years have shown no evidence of lesion recurrence. CONCLUSION: Studies have shown successful treatment of pituitary apoplexy with both surgical and non-surgical management, with surgery favored in patients with severe and/or progressive neuro-ophthalmologic deficits (1). However, there is a lack of data to guide treatment in pregnant patients. We present a case of pituitary apoplexy in pregnancy in which symptoms and hormonal function fully recovered after surgery, and imaging has been stable. Further research is needed to compare surgical and non-surgical treatment in this population, as well as the risk of tumor recurrence. (1) Marx et al. Endocrine, 2021. Presentation: No date and time listed