Introduction
-Primary adrenocortical insufficiency (Addison disease) is a syndrome resulting from the chronic deficiency of cortisol caused by adrenocortical insufficiency
-Secondary adrenocortical insufficiency is due to ACTH deficiency, caused by exogenous glucocorticoid therapy, pituitary or hypothalamic tumors
-in primary adrenal insufficiency, low or absent cortisol level results in hypersecretion of ACTH by the pituitary
-ACTH stimulates melanocyte activity, resulting in generalized hyperpigmentation, which is the most specific sign of primary adrenal insufficiency
-Addison’s disease occurs when >90% of adrenal tissue is destroyed
-The most common cause is autoimmune destruction
Symptoms & Signs
General: Weakness, malaise, anorexia, weight loss, craving for salt
Vascular: postural hypotension
GI: Nausea, vomiting, diarrhea, constipation, abdominal pain
Musculoskeletal: Myalgia, arthralgia
Metabolic: Hypoglycemia, hyponatremia,hyperkalemia
Psychiatric: Personality changes
Dermatological: Hyperpigmentation of the buccal mucosa and gums preceded by generalized hyperpigmentation of the skin, loss of axillary and pubic hair, vitiligo,calcification of auricular cartilage (petrified ears), longitudinal pigmented bands in the nails
Gynecological: Amenorrhea, ovarian failure, infertility
Obstetrical: preterm delivery, low-birth weight newborn, increase in cesarean delivery
Emergency: Shock, coma, and death, if untreated
Diagnosis
Labs: hyponatremia, hyperkalemia, acidosis, elevated serum creatinine and blood urea nitrogen, hypoglycemia, hypercalcemia
Hematology: Normochromic, normochromic anemia, neutropenia, eosinophilia, and lymphocytosis
Best screening test/Definitive diagnosis: Failure to respond adequately to corticotropin stimulation test
-MRI to rule out pituitary or hypothalamic tumor
-CT scan of the adrenal glands
-Secondary Adrenal insufficiency: Diminished pigmentation, Normal serum potassium
Treatment
-Register with a medical alert system
-Patient should be instructed in the self-administration of steroids
-Lifelong replacement therapy of glucocorticoids and mineralocorticoids
-Medications: Hydrocortisone, prednisone, dexamethasone, fludrocortisone
-Acute adrenocortical insufficiency: Medical emergency, parenteral hydrocortisone, correction of fluid and electrolytes
| Primary adrenal deficiency | Secondary adrenal deficiency |
| ACTH elevated | ACTH low or inappropriately normal |
| Aldosterone level can be low | Aldosterone level is normal |
| Hyperpigmentation | Diminished pigmentation |
| Elevated Potassium | Normal Potassium |
| Mineralocorticoid replacement needed | Mineralocorticoid replacement not needed |