Which of the following statements about Cushing’s disease is true?
Serum adrenocorticotropin (ACTH) levels usually are low
Pituitary microadenoma usually is present
There is a high incidence of nonendocrine tumors
Nonsuppression of cortisol production by the high-dose dexamethasone suppression test is a characteristic finding
Cushing’s syndrome is due to increased adrenal cortisol production, regardless of etiology.
Cushing’s disease usually is caused by a pituitary microadenoma producing high adrenocorticotropin (ACTH) levels.
In most patients, cortisol levels would be suppressed as a result of the high-dose dexamethasone suppression test.
Transsphenoidal microsurgical removal of the microadenoma is the treatment of choice in most centers.