A 58-year-old woman comes to the office after she experienced a near-fainting spell 1 day ago. She was outside playing tennis when she vomited and felt light-headed. She spent the rest of the day lying down with mild, diffuse, abdominal pain and nausea. She had no fever or diarrhea. She reports several months of worsening fatigue, mild, intermittent, generalized abdominal pain, and loss of appetite with a 10- to 15-lb unintentional weight loss. Her medical history is significant for hypothyroidism for which she takes levothyroxine. She takes no other medications. On examination, her temperature is 99.8°F, heart rate is 102 bpm, blood pressure is 89/62 mm Hg, and normal respiratory rate. She does become light-headed, and her heart rate rises to 125 bpm upon standing with a drop in systolic blood pressure to 70 mm Hg. She is alert and well tanned, with hyperpigmented creases in her hands. Her chest is clear, and her heart rhythm is tachycardic but regular. On abdominal examination, she has normal bowel sounds and mild diffuse tenderness without guarding. Her pulses are rapid and thready. She has no peripheral edema. Initial laboratory studies are significant for Na 121 mEq/L, K 5.8 mEq/L, HCO3 16 mEq/L, glucose 52 mg/dL, and creatinine 1.0 mg/dL.
1) What is the most likely diagnosis?
2) What is your next step?
3) What are the most common causes of primary and secondary adrenal insufficiency?
4) what is the treatment of adrenal insufficiency?
5) What is Stress dose of Steroids? dosage?