8695 What Comes Fast, Goes Fast: Acute Megestrol Acetate Induced Adrenal Insufficiency

Abstract Disclosure: P.N. Kabir: None. S.S. Bantu: None. F. Bril: Other; Self; Novo Nordisk. Megestrol acetate (MA; Megace®) is oftentimes used in the treatment of anorexia, cachexia, or unexplained weight loss in the setting of acquired immunodeficiency syndrome or disseminated carcinomatosis. MA is a synthetic progestin which has partial cross affinity to the glucocorticoid receptor. Its use can affect the pituitary-adrenal axis in a wide range of ways, from adrenal insufficiency (AI) to Cushing’s syndrome. We present a patient with advanced heart failure who developed acute AI after starting MA, which showed clinical and biochemical resolution after discontinuation of the medication.A 26-year-old male with a history of non-ischemic cardiomyopathy, heart failure with reduced ejection fraction, left ventricular thrombus, and CVA, who was admitted for management of heart failure exacerbation. Patient had a prolonged and complicated hospital course due to oliguric acute kidney injury requiring hemodialysis. He was subsequently diagnosed with protein calorie malnutrition. Oral calorie intake was poor and nutrition via tube feeds was insufficient, and the patient was started on MA 400 mg daily. Subsequently he developed hypotension, but after appropriate work-up, it was thought to be unrelated to cardiac etiology or infection, prompting further work up. Other causes of hypotension were ruled out, and an initial 6 am cortisol was 2.1 μg/dL. Repeat 8 am cortisol was 4.0 μg/dL, and an ACTH level was inappropriately normal at 14 pg/mL. Endocrinology service was consulted, and the recommendation was to discontinue MA. Repeat cosyntropin test results 1 week later were: cortisol at baseline 4.8μg/dL, at 30 minutes it was 19.2 μg/dL, and at 60 minutes it was 22.1μg/dL. Upon MA discontinuation, episodes of hypotension/orthostatism resolved, and the patient was discharged shortly afterwards. AI could be easily overlooked in patients taking MA due to confounding symptoms of cachexia. Moreover, because of the partial agonism of glucocorticoid receptor, many of the symptoms of MA-induced AI may be mild. Indeed, MA has been frequently associated with Cushing’s syndrome or AI upon discontinuation of the drug. Our case illustrates a patient that presented with acute MA-induced AI, which resolved quickly after MA discontinuation. Literature review mentions use of MA for weeks prior to development of AI usually seen with doses more than 400 mg/day. There is limited data regarding the timeline for resolution of AI, although it has been reported that symptoms usually resolve within days to months off the MA. Early recognition and prompt diagnosis of AI in patients initiating MA can prevent severe complications, such as adrenal crisis, as early discontinuation of MA can result in reversal of AI symptoms, avoiding the use of steroids to treat these individuals. Presentation: 6/2/2024