7412 A Case of Exogenous Cushing Syndrome in a Patient with History of Acromegaly Status Post Transsphenoidal Resection Complicated by Panhypopituitarism Requiring Glucocorticoid Replacement

Abstract Disclosure: A. Capozza: None. C. Heluey: None. S.S. Chaidarun: None. Introduction: Exogenous Cushing syndrome is a complication of long-term glucocorticoid therapy. Frequency of Cushingoid features such as truncal obesity, buffalo hump, moon faces, weight gain, striae, ecchymosis, and skin thinning increases as the glucocorticoid dose increases. Here we present a case of exogenous Cushing syndrome in a patient with history of acromegaly status post transsphenoidal resection of adenoma complicated by panhypopituitarism requiring glucocorticoid replacement. Clinical Case: A 37-year-old female with history of acromegaly status post transsphenoidal resection of somatotroph/thyrotroph adenoma in 2019 complicated by panhypopituitarism, diabetes insipidus, and type 2 diabetes was admitted after presenting with diarrhea and electrolyte derangements. At home, the patient was on desmopressin 0.1 mg nightly, dexamethasone 1.5 mg daily, levothyroxine 175 mcg nightly, and estradiol 1 mg daily. Her dexamethasone dose had been increased from 0.75 mg-1 mg daily to 1.5 mg daily over the years due to hypoglycemia. At time of admission, labs were significant for free T4 of 2.20 (0.93-1.70 ng/dL), free T3 1.7 (2-4.4 pg/mL), sodium 130 (135-145 mmol/L), potassium 2.8 (3.5-5 mmol/L), calcium 7.4 (8.5-10.5 mg/dL), phosphorous 1.0 (2.5-4.5 mg/dL), PTH 237 (15-65 pg/mL), 25-OH vitamin D 39 (21-100), 1,25 vitamin D 31 (18-78 pg/mL), and glucose 207 (65-199 mg/dL). On physical exam, she had signs of acromegaly including large tongue, thick lips, large nose, prognathism, frontal bossing, and deep voice. She also appeared Cushingoid with rounded face, thin skin, multiple areas of ecchymosis, wide purple striae over the abdomen and upper arms, posterior cervical hump, supraclavicular fullness, and trunk obesity. Long-term, supra-physiologic dose glucocorticoids were thought to be the cause of her Cushingoid appearance. Glucocorticoids were also contributing to hyperglycemia and reduced conversion of free T4 to free T3. Conclusion: Glucocorticoids have numerous adverse effects such as hyperglycemia, exogenous Cushing syndrome, osteoporosis to name a few. Higher doses and longer duration of glucocorticoids carry a higher risk of adverse effects. This case illustrates the importance of thorough physical exam and frequent assessment for adverse effects in patients on glucocorticoids. Both acromegaly and Cushing syndrome render poor health outcomes, so optimal treatment and long-term care of post-surgical hypopituitarism is important. Presentation: 6/3/2024