A 27-Year-Old Woman Presented to the ER Complaining of Nausea

A 27-year-old woman presented to the ER complaining of nausea and vomiting for 1 week. She also reported 8 months of progressively worsening fatigue. The patient was previously very active as a ballet student, but for the past 8 months she stopped participating in ballet because of lack of energy and poor concentration. One week prior to admission, she developed nausea and had several episodes of vomiting which provoked her visit to the ER. She also reported a poor appetite for months and had lost 10 lb. Physical examination showed dryness and darkening of the skin in several areas. She repeatedly denied purposefully restricting food intake or binging and purging behaviors. There was no abdominal pain, diarrhea, fevers, dysuria, or headache. As the attending physician you suspect this patient is exhibiting signs of Addison disease. Testing for which of the following would be most useful in your diagnosis?

A) decreased plasma estrogen
B) decreased urinary cortisol
C) increased plasma ACTH
D) increased plasma aldosterone
E) increased plasma cortisol