A 49-year-old man comes to the physician because of a 4-month history of gradually worsening fatigue. He has lost 5 pounds during this time. He has no past medical history and works as a carpenter. Vitals are: temperature 98.5 F, RR 12, HR 70, BP 100/60. BMI is 24. Fasting glucose is 80 mg/dL. Physical examination shows slight darkening of the skin of the forearms. Serum ACTH is elevated. Which of the following is most likely to be seen in this patient?
A) Decreased corticotropin releasing hormone
B) Eosinophils of 15%
C) Failure of suppression with high-dose Dex
D) Hilar coin lesion
E) Serum sodium of 147 mEq/L
