A 32 year-old man complains of fatigue, weakness, edema and acne for 6 months. He is 70in tall and weighs 220 Ib. His blood pressure is 148/90 mmHg. He has central obesity, enlarged subclavicular fat pads and prominent abdominal striae. His lab tests are:
The 24-hour urine cortisol excretion is 288
Serum cortisol level is 18 at 8:00 am after taking 1 mg of dexamethasone at bedtime and next day it was 18.9 after at 8:00 am after taking 8 mg of dexamethasone at bedtime.
Plasma ACTH level is 281
What is the most likely site of the disorder causing Cushing syndrome in this patient?
A- Pituitary gland
B- Hypothalamus
C- Lungs
D- Adrenal glands
E- Pancreas
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