ESSENTIALS OF DIAGNOSIS
Weakness, vomiting, diarrhea; abdominal pain, arthralgias; amenorrhea.
Sparse axillary hair; increased skin pigmentation, especially of creases, pressure areas, and nipples.
Hypotension, small heart.
Hyponatremia; potassium, calcium, and BUN elevated; mild anemia and relative neutropenia, lymphocytosis, and eosinophilia.
Plasma ACTH level elevated; cosyntropin unable to stimulate serum cortisol to 20 mcg/dL (550 nmol/L) or more.
Acute adrenal crisis: above manifestations become critical, with fever, shock, confusion, coma, death.
Primary adrenal insufficiency (Addison disease) is caused by dysfunction or absence of the adrenal cortices. It is distinct from secondary adrenal insufficiency caused by deficient secretion of ACTH. (See Anterior Hypopituitarism.)
Addison disease is an uncommon disorder with a prevalence of about 140 per million and an annual incidence of about 5 cases per million in the United States. Addison disease is characterized by a chronic deficiency of cortisol. Serum ACTH and alpha-MSH levels are consequently elevated, causing pigmentation that ranges from none to strikingly dark. Patients with destruction of the adrenal cortices or with classic 21-hydroxylase deficiency also have mineralocorticoid deficiency, typically with hyponatremia, volume depletion, and hyperkalemia. In contrast, mineralocorticoid deficiency is not present in patients with familial corticosteroid deficiency and Allgrove syndrome.
Acute adrenal (addisonian) crisis is an emergency caused by insufficient cortisol. Crisis may occur in the course of treatment of chronic adrenal insufficiency, or it may be the presenting manifestation of adrenal insufficiency. Acute adrenal crisis is more commonly seen in primary adrenal insufficiency than in secondary adrenal insufficiency.
Adrenal crisis may occur in the following situations: (1) during stress (eg, infection, trauma, surgery, hyperthyroidism, or prolonged fasting) in a patient with latent or treated adrenal insufficiency; (2) following sudden withdrawal of adrenocortical hormone in a patient with chronic insufficiency or in a patient with temporary insufficiency due to suppression by exogenous corticosteroids or megestrol (eFigure 26–23); (3) following bilateral adrenalectomy or removal of a functioning adrenal tumor that had suppressed the other adrenal gland; (4) following sudden destruction of the pituitary gland (pituitary necrosis), or when thyroid hormone is given to a patient with adrenal insufficiency; (5) following injury to both adrenals (by trauma, hemorrhage, anticoagulant therapy, thrombosis, infection or, rarely, metastatic carcinoma); and (6) following administration of intravenous etomidate (used for rapid anesthesia induction or intubation).
Pattern of plasma ACTH and cortisol values in patients recovering from prior long-term daily treatment with large doses of corticosteroids. (Courtesy of R Ney. Reproduced, with permission, from Ganong WF. Review of Medical Physiology, 19th ed. Copyright © 1999 by The McGraw-Hill Companies, Inc.)
Autoimmunity is the most common cause of Addison disease in industrialized countries, accounting for about 90% of spontaneous cases. With such autoimmunity, adrenal function decreases over several years as it progresses to overt ...