Adrenal insufficiency

Differential Diagnosis

• Inflammatory/Autoimmune
  • Primary (autoimmune) adrenal insufficiency
  • Sarcoidosis
  • Antiphospholipid syndrome
• Infectious
  • Tuberculosis
  • Meningococcemia causing Waterhouse-Friderichsen syndrome
  • HIV, CMV
  • Histoplasmosis
• Malignancy
  • Metastases, especially breast cancer
• Other
  • Systemic anticoagulation
  • Adrenoleukodystrophy

Management

• Treat with dexamethasone while awaiting result of ACTH stimulation test to confirm diagnosis
  • At 1h after ACTH, cortisol should be above 550 and have increased by 250
• Stress dosing, to be given for 24h unless ongoing illness
  • Hydrocortisone 300mg (divided q8h)
  • Prednisone 60mg
  • Methylprednisolone 50mg
  • Dexamethasone 8mg
• After stress dosing, can deescalate quickly to physiologic doses
  • Prednisone 7.5mg daily or 5mg/2.5mg split, with fludrocortisone 0.1mg daily
  • Hydrocortisone 20mg/10mg split, without fludrocortisone
• For future stress dosing during intercurrent illnesses, can simply double dose when febrile