FAMILY MEDICINE® COLUMN
By John C. Wolf, D.O.
Associate Professor of Family Medicine®
Ohio University College of Osteopathic Medicine

IN ADDISON'S DISEASE, BODY TRIES TO "KILL" ITS OWN ADRENAL GLAND

Question: My friend was diagnosed with Addison's disease. What happens in this illness, and what causes it?

Answer: Addison's disease is an illness named after Thomas Addison, the British physician who described the illness in the 1800s. A much better name for this illness is the newer term that describes the underlying abnormality chronic adrenal insufficiency, although the older term, Addison's disease, is still used quite commonly.

The adrenal glands are part of the body's hormone-manufacturing machinery, and in this illness, they fail to produce a sufficient quantity of the hormone cortisol. This hormone, like all hormones, is produced by one tissue in this case the adrenal glands which are located atop the kidneys. All hormones, once produced, are conveyed by the bloodstream to other parts of the body to affect the metabolism and other activities of these distant organs.

The adrenal glands release their hormones into the blood in response to the level of the regulating hormone ACTH, produced by an organ at the base of the brain called the pituitary gland. In chronic adrenal insufficiency, the adrenal gland is damaged and unable to respond to the stimulation of ACTH. The pituitary gland attempts to correct the low levels of cortisol by increasing the amount of ACTH it produces.

The pituitary gland makes many hormones. One of these controls skin pigmentation. This hormone, released at the same time as ACTH, is pumped into the bloodstream in increased amounts because of the elevated ACTH production. The high levels of this second hormone cause one of the common physical symptoms of Addison's disease increased skin pigmentation.

The increased skin pigment is particularly noticeable when looking at the creases of the palms, elbows and other places the skin routinely folds. There is also increased pigment around the nipples and where the skin is chronically irritated by pressure, such as the belt line. General weakness, loss of appetite with resultant weight loss, and low blood pressure are other common signs of this illness. So this describes "what happens" in Addison's disease.

Chronic adrenal insufficiency results from an auto-immune illness in 70 percent of cases. This occurs when the body's defense mechanisms inappropriately identifies the adrenal gland as an invader as though it was an infecting bacteria and tries to kill it. There are no widely accepted explanations for the cause of this or other auto-immune illnesses.

About 20 percent of those with Addison's disease develop it as a consequence of an infection in the adrenal gland. The most common cause of this is tuberculosis, but histoplasmosis, sarcoidosis, and blastomycosis can also attack the gland. About 5 percent of individuals have AIDS as the cause of their adrenal insufficiency, and less than 5 percent have cancer or other illness as the cause.

Question: My friend had symptoms for years before she finally was treated for Addison's disease. Is the treatment any better if the illness is identified early?

Answer: Death can result from untreated chronic adrenal insufficiency while early treatment can lead to a normal life. So, early diagnosis and treatment is clearly an advantage. The specific treatment depends on the severity of symptoms as well as the underlying cause. In the most common auto-immune cause, replacement of the missing adrenal hormone is the proper treatment. Adrenal insufficiency caused by infection or cancer responds best to treatment of the underlying disease. It is usually necessary to take supplemental adrenal hormones in these illness, too. But, as the gland recovers from the original disease, it may begin to function properly again and make the daily supplement of cortisone unnecessary.

Family Medicine® is a weekly column. To submit questions, write to John C. Wolf, D.O., Ohio University College of Osteopathic Medicine, Grosvenor Hall, Athens, Ohio 45701.