Sections View Full Chapter Figures Tables Videos Annotate Full Chapter Figures Tables Videos Supplementary Content +++ KEY FEATURES +++ ESSENTIALS OF DIAGNOSIS ++ Inability to increase serum cortisol to > 20 mg/dL in response to synthetic adrenocorticotropic hormone (ACTH) during rapid ACTH stimulation testing Orthostatic hypotension, urinary salt wasting, and serum hyperkalemia in primary adrenal insufficiency (Addison’s disease) Hyponatremia in both primary and secondary (pituitary) adrenal insufficiency Elevated ACTH in Addison’s disease Hypovolemic shock, hypoglycemia, and fever in adrenal crisis +++ GENERAL CONSIDERATIONS ++ Primary adrenal insufficiency (Addison’s disease) is caused by destruction of the adrenal cortex usually by an autoimmune disease today (granulomatous diseases such as tuberculosis in the past) Secondary adrenal insufficiency is usually caused by withdrawal of steroids, which depress the hypothalamic pituitary adrenal axis resulting in ACTH hyposecretion, which leads to decreased adrenal glucocorticoid production Incidence in the general population is < 0.01%, but occurs more commonly in critically ill patients, especially those over age 55 who are hypotensive +++ CLINICAL PRESENTATION +++ SYMPTOMS AND SIGNS ++ Fatigue Anorexia, nausea, vomiting, abdominal pain, weight loss Depressed mentation, syncope, coma +++ PHYSICAL EXAM FINDINGS ++ Hyperpigmented skin if chronic; vitiligo if autoimmune Decreased pubic and axillary hair Dehydration Hypotension Fever +++ DIFFERENTIAL DIAGNOSIS ++ Other causes of orthostatic hypotension Other causes of hypovolemic shock Other causes of hyperkalemia, hyponatremia, hypercalcemia, hypoglycemia, and acidosis +++ DIAGNOSTIC EVALUATION +++ LABORATORY TESTS ++ Electrolytes and glucose show: hyponatremia, hyperkalemia (if primary), hypercalcemia, hypoglycemia, and acidosis CBC: anemia, lymphocytosis, and eosinophilia Serum cortisol < 25 mg/dL in critically ill patients; elevated in primary adrenal insufficiency +++ ELECTROCARDIOGRAPHY ++ Sinus bradycardia or tachycardia Nonspecific ST-T–wave changes Signs of hyperkalemia (peaked T waves) Short QT if hypercalcemic +++ IMAGING STUDIES ++ Echocardiogram shows small cardiac chambers with normal function +++ DIAGNOSTIC PROCEDURES ++ Rapid ACTH stimulation test causes cortisol to increase to ≥ 20 mg/dL in primary adrenal insufficiency +++ TREATMENT +++ CARDIOLOGY REFERRAL ++ Significant cardiac arrhythmias +++ HOSPITALIZATION CRITERIA ++ Suspected adrenal insufficiency +++ MEDICATIONS ++ Hydrocortisone 100 mg IV every 6–8 hours acutely Saline and glucose IV Treatment of precipitating infection Long-term adrenal hormone replacement, such as hydrocortisone PO 20 mg in the morning and 10 mg in the evening, plus fludrocortisone 0.05–0.1 mg PO daily in primary adrenal insufficiency +++ MONITORING ++ ECG in hospital as appropriate +++ DIET AND ACTIVITY ++ High-sodium diet and fluids until condition is controlled by therapy Restricted activity until treatment is underway +++ ONGOING MANAGEMENT ... Your Access profile is currently affiliated with [InstitutionA] and is in the process of switching affiliations to [InstitutionB]. Please select how you would like to proceed. Keep the current affiliation with [InstitutionA] and continue with the Access profile sign in process Switch affiliation to [InstitutionB] and continue with the Access profile sign in process Get Free Access Through Your Institution Learn how to see if your library subscribes to McGraw Hill Medical products. Subscribe: Institutional or Individual Sign In Error: Incorrect UserName or Password Username Error: Please enter User Name Password Error: Please enter Password Sign in Forgot Password? Forgot Username? Download the Access App: iOS | Android Sign in via OpenAthens Sign in via Shibboleth You already have access! Please proceed to your institution's subscription. Create a free profile for additional features.