Cushing's Syndrome Diagnosis and Management

Introduction to Cushing's Syndrome

• The American Heart Association recommends that blocking the mineralocorticoid actions of excess cortisol with spironolactone or eplerenona is the most sensible strategy for hypertension in Cushing's syndrome 1
• The Endocrine Society and ACC/AHA guidelines recommend starting with 2-3 screening tests, including cortisol-free urinary excretion, nocturnal salivary cortisol, and a dexamethasone suppression test 2, 6

Diagnostic Approach

• The Endocrine Society recommends that any of the three tests, including post-dexamethasone cortisol, cortisol-free urinary excretion, and nocturnal salivary cortisol, can confirm hypercortisolism 2
• The lack of suppression of morning cortisol (<1.8 μg/dL or <50 nmol/L) after 1 mg of dexamethasone at night is a standard confirmatory test for Cushing's syndrome 2, 6, 7, 8

Management of Cushing's Syndrome

• Surgery is the first-line treatment to remove the source of cortisol production (pituitary adenoma, adrenal tumor, or ectopic tumor) 3, 4
• Medical management with steroidogenesis inhibitors (ketoconazole, metyrapone) is reserved for non-surgical patients or as a bridge to surgery 3, 4, 2

Treatment Guidelines

• The American College of Cardiology recommends that spironolactone is the most appropriate initial anti-hypertensive management in Cushing's syndrome because it blocks the mineralocorticoid receptors that mediate hypertension due to excess cortisol 1, 5
• The American Heart Association establishes that conventional anti-hypertensives (ACE inhibitors, ARB-II, calcium antagonists) may not be effective in achieving blood pressure targets in Cushing's syndrome 5