FRI346 Can We Miss Panhypopituitarism After Transsphenoidal Surgery?

Disclosure: A. Makawi: None. J. Huynh: None. G. Elshimy: None. Introduction: Disorders of water and osmolality due to aberrant ADH secretion and posterior pituitary function are common causes of morbidity among patients who undergo transsphenoidal hypophysectomy surgery (TSS). Postoperatively, central diabetes insipidus (DI) may present as a complication in up to 30% of cases. Moreover, hypopituitarism is an important complication of TSS, and can manifest as adrenal crises if missed by clinicians. We present a patient who underwent TSS for pituitary adenoma with postoperative course complicated by hypogonadism that was misdiagnosed for 10 years. Additionally he developed DI, secondary adrenal insufficiency (AI), and central hypothyroidism after resolution of his central hypogonadism. Case Description: 64-year-old male with medical history significant for chronic hypogonadism on hormonal replacement therapy and diabetes, presented for sleep disturbance and deviated septum with incidental finding of a large sphenoidal mass on CT imaging. MRI of brain confirmed a 4 cm macroadenoma invading from the inferior sella into the bilateral cavernous sinuses, clivus, and sphenoid sinus. Patient was then referred to neurosurgery for transsphenoidal resection. Patient underwent surgery and perioperative course complicated by a small CSF leak. He stayed in the neuro-ICU after the surgery and was monitored by the surgical team without endocrine consultation. He was discharged without proper postoperative evaluation of the HPA axis or education on symptoms of pan-hypopituitarism. Shortly after, he experienced significant symptoms consistent with adrenal insufficiency which prompted a visit to the emergency room. Thereafter, he finally presented to the neuroendocrine clinic for follow-up. Labs were notable for cortisol 1.2 mcg/dl, TSH 0.018 mcIU/ml, FT4 0.2ng/dl, and Na 130 mEq/ml, normal testosterone 551 ng/dl, mildly persistently elevated Na 147 mEq/ml with positive water deprivation test confirming central DI. He was treated with hydrocortisone and Synthroid for adrenal insufficiency and hypothyroidism respectively and was started on desmopressin for central DI. Discussion: Pan-hypopituitarism frequently occur after neurosurgical interventions and failure to involve endocrinology in the management of these cases may lead to missed diagnoses, unnecessary morbidity and mortality. This report serves as an excellent illustration of the importance of both surgical and medical management to prevent life-threatening complication such as adrenal crises as a result from pan-hypopituitarism. Presentation: Friday, June 16, 2023