A 60 year old male presented with skin hyperpigmentation, central obesity, violet striae & proximal myopathy. His BP is 160/90 mmHg. Lab studies show hypokalemic metabolic alkalosis. Which of the following statements is true regarding this condition?
Basal ACTH level is likely to be low.
Circulating coicotropin-releasing hormone is likely to be elevated.
Pituitary magnetic resonance imaging (MRI) will visualize all ACTH-secreting tumors.
Serum potassium level <3.3 mmol/L is suggestive of ectopic ACTH production
The given scenario suggests the diagnosis of Cushing syndrome. Basal ACTH levels are elevated in pituitary tumors & ectopic ACTH secretion Coicotropin-releasing hormone is rarely the cause of Cushing syndrome. MRI of the pituitary gland will not visualize lesions <2 mm Serum potassium level <3.3 mmol/L is suggestive of ectopic ACTH production Also, hypeension, hypokalemic metabolic alkalosis & glucose intolerance are more prominent in ectopic ACTH secretion than in pituitary tumors
Cushing Syndrome