SAT328 Severe Exogenous Cushing Syndrome Caused By A Potent Steroid Concealed In Arthritis Supplement

Abstract Disclosure: S. Maraqa: None. L. Bushnaq: None. R. Singh, PhD: None. N. Genere: None. Cushing syndrome (CS) is a rare disorder caused by excessive systemic glucocorticoids and associated with increased mortality and worsening quality of life. CS most commonly occurs from exogenous glucocorticoid use, while Cushing disease causes most of endogenous cases. Here, we present a case of a 64-year-old woman with rapidly progressive CS due to an over-the-counter (OTC) arthritis supplement with unlisted dexamethasone. A 64-year-old woman with reported CS who was evaluated in our Endocrinology center after she moved to the United States. She was previously diagnosed with pituitary CS in Mexico following a 6 months history of rapid 50-pound weight gain, profound proximal muscle weakness requiring assistive device, and unprovoked vertebral fractures; laboratory evaluation found elevated 24-hour urinary cortisol 272 mcg/24h, 1mg dexamethasone suppression test total cortisol 5.6 mcg/dl (< 1.8), and adrenocorticotropic hormone (ACTH) 16 pg/mL. Pituitary MRI was unremarkable. Past medical history included primary hypothyroidism and hypertension. Physical exam was notable for blood pressure 160/108 mmHg, heart rate 96, BMI 33 kg/m², moon face, supraclavicular fat pads, central obesity, skin bruises, and proximal muscle weakness. Unexpectedly, re-evaluation showed undetectable serum ACTH and cortisol. A thorough review of medications identified no recent exposure to glucocorticoids. However, a synthetic glucocorticoid screen showed markedly elevated serum dexamethasone concentration. Follow-up discussion revealed that she had started an arthritis supplement “Artri-King” 6 months prior to these symptoms. We collaborated with Mayo Clinic Labs to evaluate dexamethasone contents in this drug; each tablet was found to contain 0.9 mg of dexamethasone, which was unreported in the ingredient list. This supplement was stopped, and the patient was started on physiologic hydrocortisone. Two months later, AM cortisol was 5.6 mcg/dL and ACTH 23 pg/ml. Eight months later, she continues to have adrenal insufficiency but has had a substantial clinical improvement.Exogenous CS is readily diagnosed in patients taking prescribed glucocorticoids; however, diagnosis can be more challenging in cases where the presence of glucocorticoids is concealed. The US Food and Drug Administration follows more limited regulatory guidelines for dietary supplements compared to prescribed drugs. A study by Tucker.et.al. reported that 20% of dietary supplements have unapproved ingredients.1 This is especially concerning, considering that over half of the US population admits to taking dietary supplements.2 On April 2022, the FDA published a public notice for “Artri-King”, declaring the presence of unlisted dexamethasone.3 Should such agents prove to be the culprit of CS, they must be tapered off gradually or in the presence of physiologic hydrocortisone to avoid the risk of adrenal crisis. Presentation: Saturday, June 17, 2023