Addison’s disease
Addison’s disease
Addison’s disease (also called adrenocortical deficiency, primary adrenal hypofunction, chronic adrenal insufficiency, and hypocortisolism) is a rare condition caused by destruction of the cortex of the adrenal gland, one of several glands the endocrine system. Because Addison’s disease is treatable, those who develop the illness can expect to have a normal life span. One of the more well-known persons to have Addison’s disease was U.S. President John F. Kennedy (1917–1963).
The adrenal glands
The adrenal glands, also called suprarenal glands, sit like flat, triangular caps atop each kidney. They are divided into two distinct areas-the medulla at the center and cortex surrounding the outside. The cortex, which makes up about 80% of the adrenal gland, secretes three types of hormones—sex hormones, mineralocorticoids (principally aldosterone), and glucocorticoids (primarily cortisol or hydrocortisone). Scientists believe these hormones perform hundreds of regulatory functions in the body, including helping to regulate metabolism, blood pressure, the effects of insulin in the breakdown of sugars, and the inflammatory response of the immune system. Addison’s disease results from an injury or disease that slowly destroys the adrenal cortex, therefore shutting down the production of these hormones.
The production of cortisol by the adrenal cortex is precisely metered by a control loop that begins in an area in the brain called the hypothalamus, a collection of specialized cells that control many of the functions of the body. When necessary, the hypothalamus secretes a releasing factor that tells the pituitary gland to secrete another hormone to stimulate the adrenal gland to release more cortisol. The increased cortisol levels signal the pituitary to stop producing the adrenal stimulant. This is a finely tuned loop, and if it is interrupted or shut down, as in Addison’s disease, profound changes occur in the body.
History of Addison’s disease
The disease is named for its discoverer, British surgeon Thomas Addison (1793–1860), who described adrenal insufficiency in 1849, though endocrine functions had yet to be explained. Addison later wrote a publication called On the Constitutional and Local Effects of Disease of the Suprarenal Capsules, which provided more details on the disease. Addison described the condition from autopsies he performed. At the time, there was no cure for adrenal insufficiency, so victims died after contracting it. Addison also noted that 70 to 90% of patients with adrenal insufficiency had tuberculosis as well.
Addison’s disease is no longer a fatal illness if it is properly diagnosed. Today, doctors note that up to 70% of cases are the result of the adrenal cortex being destroyed by the body’s own immune system, so Addison’s is called an autoimmune disease. Those who have sustained an injury to the adrenal gland and people who have diabetes are at increased risk of Addison’s disease. Tuberculosis is also linked to the disease, but since this disease can now be cured, Addison’s disease is rarely caused by tuberculosis today.
Addison’s disease
The effects of adrenal insufficiency do not manifest themselves until more than 90% of the adrenal cortex has been lost. Then, weakness and dizziness occur, and the skin darkens, especially on or near the elbows, knees, knuckles, lips, scars, and skin folds. These symptoms begin gradually and worsen over time.
The patient becomes irritable and depressed and often craves salty foods. Some people do not experience these progressive symptoms, but become aware of the disease during what is called an addisonian crisis. In this case, the symptoms appear suddenly and require immediate medical attention. Severe pain develops in the lower back, abdomen, or legs; vomiting and diarrhea leave the patient dehydrated. A person may become unconscious and may even die.
A doctor’s examination reveals low blood pressure that becomes even lower when the patient rises from a sitting or lying position to a standing position. A blood test shows low blood sugar (hypoglycemia), low blood sodium (hyponatremia), and low levels of cortisol. Other tests are carried out to determine whether the condition is the result of adrenal insufficiency or if the low levels of cortisol are the result of problems with the hypothalamus or pituitary.
Treatment
Once diagnosed, Addison’s disease is treated by replacing the natural cortisol with an oral medication. The medicine is adjusted by a doctor to bring cortisol levels in the blood up to normal and maintain them. A patient also is advised to eat salty foods, not skip any meals, and carry a packet containing a syringe with cortisone to be injected in case of an emergency.
With the loss of the ability to secrete cortisol under stress, a patient must take extra medication when he/she undergoes dental treatments or surgery. Even though Addison’s disease is not curable, a patient with this condition can expect to live a full life span.
See also Adrenals; Diabetes mellitus; Insulin.
Resources
BOOKS
Langford, Rae. Mosby’s Handbook of Diseases. St. Louis, MO: Elsevier Mosby, 2005.
Litin, Scott C., ed. Mayo Clinic Family Health Book. New York: HarperResource, 2003.
The Official Patient’s Sourcebook on Addison’s Disease: A Revised and Updated Directory for the Internet Age. San Diego: ICON Health Publications, 2002.
Tamparo, Carol D. Diseases of the Human Body. Philadelphia, PA: F.A. Davis Company, 2005.
PERIODICALS
Erickson, Q.L. “Addison’s Disease: The Potentially Life-threatening Tan.” Cutis 66, no. 1 (2001): 72-74.
National Institute of Diabetes and Digestive and Kidney Diseases. “Addison’s Disease.” (fact sheet). National Institutes of Health Publication No. 90-3054.
Ten, S. “Addison’s Disease 2001.” The Journal of Clinical Endocrinology & Metabolism 86, no. 7 (2001): 2909-2922.
Larry Blaser