Which of the following best describes idiopathic Cushing syndrome due to cortisol excess?

• A. Hyperpigmentation with hypokalemia.
• B. Weight loss with hypotension.
• C. Central obesity with moon facies, buffalo hump, and proximal muscle wasting.
• D. Hyperglycemia with fasting plasma glucose.

Answer: (C)

Hypercortisolism from cortisol excess produces a characteristic fat redistribution pattern: central (truncal) obesity with facial rounding (moon facies) and a dorsocervical fat pad (buffalo hump), accompanied by proximal muscle wasting from cortisol’s catabolic effects on skeletal muscle. This combination is the classic presentation of endogenous Cushing syndrome, which fits the scenario described as idiopathic cortisol excess. The other descriptions reflect processes not typical of cortisol excess: hyperpigmentation with hypokalemia suggests adrenal insufficiency or ACTH-related issues with mineralocorticoid effects, weight loss with hypotension points to cortisol deficiency, and hyperglycemia can occur in many conditions but does not capture the specific fat redistribution and muscle wasting hallmark of Cushing.