Adrenal insufficiency
Formal Definition
Inadequate production of cortisol (and often aldosterone) from the adrenal cortex; classified as primary (Addison disease — adrenal gland destruction, most commonly autoimmune) or secondary (hypothalamic-pituitary dysfunction or abrupt glucocorticoid withdrawal); can present acutely as an adrenal crisis with hypotension, hyponatremia, hyperkalemia, and hypoglycemia.
How It's Used on the Ward
"AI" or "adrenal crisis" — the feared state of cortisol deficiency, often unmasked by physiologic stress in a patient on chronic steroids who misses doses.
Example
""Post-op day 2 patient on chronic prednisone for RA suddenly hypotensive to 70s systolic, sodium 127, glucose 58 — stress-dose steroids now, 100 mg hydrocortisone IV bolus, then q8h. Cannot wait for cosyntropin stim test in an unstable patient.""
Clinical Context
Classic electrolytes in primary adrenal insufficiency: hyponatremia + hyperkalemia (aldosterone deficiency) + hypoglycemia + eosinophilia. Secondary AI: cortisol deficiency only (aldosterone preserved via renin-angiotensin, so no hyperkalemia). Adrenal crisis = life-threatening: hypotension that does not respond to fluids, Treat first: hydrocortisone 100 mg IV bolus. Do NOT wait for cortisol levels if unstable. Stress dosing: double or triple baseline dose during illness/surgery. Carry Medical Alert ID. Steroids must not be stopped abruptly after >3 weeks of use (HPA suppression).