AEMCA Practice Exam

What is a primary characteristic of Cushing's syndrome?

1. Underproduction of cortisol

2. Overproduction of cortisol

3. Normal release of ACTH

4. Increase in insulin sensitivity

The correct answer is: Overproduction of cortisol

The primary characteristic of Cushing's syndrome is the overproduction of cortisol. Cushing's syndrome occurs due to prolonged exposure to elevated levels of cortisol, which can result from various causes, including a tumor on the pituitary gland that secretes excessive adrenocorticotropic hormone (ACTH), leading to increased cortisol production by the adrenal glands. Cortisol is crucial in various bodily functions, including metabolism and the stress response; however, when produced in excess, it can lead to several signs and symptoms such as weight gain, skin changes, and hypertension. The other options do not accurately describe Cushing's syndrome. Underproduction of cortisol would be indicative of conditions such as Addison's disease, which is the exact opposite. A normal release of ACTH would imply that there is no abnormal stimulation of cortisol and would generally not be consistent with Cushing's. An increase in insulin sensitivity does not correlate with the pathophysiology of Cushing's syndrome, as individuals with this condition often experience insulin resistance. This highlights why overproduction of cortisol is the definitive characteristic of Cushing's syndrome.