SUN-186 Case Report: Mifepristone Taper in an Individual with Equivocal Cushing’s Syndrome Screening Tests

Abstract

We present a 75-year-old male evaluated by the inpatient endocrine service during an admission for hemorrhagic stroke. Approximately 1 year prior to this admission he was started on mifepristone therapy for presumed Cushing’s Syndrome. Initial Cushing’s work-up was equivocal: 1 mg dexamethasone suppression cortisol level of 1.9 and midnight salivary cortisol 167 ng/dl. Random ACTH measurement was not obtained as part of this initial evaluation. Review of prior imaging studies did not demonstrate obvious culprit pituitary nor adrenal lesions. Mifepristone induced hyperaldosteronism, thyroid dysfunction and adrenal insufficiency were demonstrated presumably secondary to cortisol receptor antagonist induced up-regulation of adrenocorticotropic hormone and cortisol. We describe our experience stopping mifepristone and performing re-evaluation. We propose a tapering protocol in the setting of potentially untreated Cushing’s Syndrome and suggest use as a bridge therapy to surgical intervention rather than destination therapy.