Addison disease occurs when the adrenal glands are no longer able to produce certain hormones needed for life, such as cortisol and aldosterone.
There are two adrenal glands in the body, one on top of each kidney. They produce two hormones: cortisol and aldosterone.
Cortisol
Cortisol is a type of hormone called a glucocorticoid. It affects almost every organ and tissue in the body. Experts believe cortisol may have hundreds of effects, but its main job is to help the body respond to stress. Other vital tasks include the following.
Cortisol is vital to health, so the body maintains a precise balance. As with many other hormones, the hypothalamus and pituitary gland are key to this control.
Aldosterone
Aldosterone is a type of hormone called a mineralcorticoid. It helps with the following functions:
Addison disease is a rare disorder that affects only about 1 in every 100,000 people. It occurs in all age groups, and affects both men and women equally. Addison disease may be caused by either a disorder of the adrenal glands themselves, which is called primary adrenal insufficiency. Or, it may be caused by inadequate secretion of ACTH by the pituitary gland. In primary adrenal insufficiency, an autoimmune disorder that makes the person's own immune system attack and destroy the outer layer of the adrenal glands, called the cortex, is often at fault. When at least 90 percent of the cortex has been destroyed, adrenal insufficiency occurs. Experts believe causes for this type may include:
Secondary adrenal insufficiency is due to a lack of ACTH, which causes the adrenal glands to produce less cortisol. It does not affect production of aldosterone. Causes of this type of insufficiency include:
In most cases, the symptoms come on gradually. Addison disease commonly causes these symptoms:
If symptoms progress too long without treatment, the person may go into an addisonian crisis. Symptoms of this crisis include:
Without treatment, addisonian crisis can be fatal.
In its early stages, Addison disease can be hard to diagnose. Diagnosis of Addison disease begins with a medical history and physical exam. Dark tanning of the skin is will often lead the doctor to suspect Addison disease. Blood tests, such as the ACTH stimulation test, can confirm the low cortisol level and its effects on the body. X-ray exams of the adrenal and pituitary glands may be helpful in identifying the cause of the disease.
Usually, nothing can be done to prevent Addison disease. People with certain infections such as tuberculosis can sometimes avoid this condition if the infection is treated early.
Shock and death can result if the condition is not treated. With treatment, there are generally no long-term effects. In life-threatening situations and illnesses, a person may need increased doses of hormones given as pills or shots to help the body adapt.
Addison disease poses no risks to others.
Treatment of Addison disease involves replacing the missing adrenal hormones. Initial therapy may include IV fluids, other medicines to support blood pressure or treat infections, and IV hormones. Once a person is stable, hormone pills alone can be used. Patients who need to replace aldosterone may also be advised by their doctors to increase their salt intake.
Medicines to support blood pressure or treat infections may cause allergic reactions and stomach upset. If hormones are given in too low or too high an amount, uncomfortable symptoms can result. For example, if adrenal hormone levels are too high, people can have mood swings and body swelling.
In most cases, lifelong hormone replacement is required because adrenal function does not usually return to healthy levels once it is lost. People with Addison disease should wear or carry identification, such as a Medic Alert bracelet, describing their condition and emergency treatment needed. When people with this disease travel, they should bring along an injectable form of cortisol that can be used in case of emergency. A plan for increasing cortisol medicine dosing during periods of high stress or with mild respiratory infections should also be discussed with the doctor.
Blood tests can be used to check for salt balance and hormone levels. Immediate medical attention will be needed if the person develops a severe infection or severe vomiting and diarrhea. These conditions can bring on addisonian crisis. Any new or worsening symptoms should be reported to the doctor as well.
Author:Adam Brochert, MD
Date Written:
Editor:Crist, Gayle P., MS, BA
Edit Date:09/23/02
Reviewer:Kathleen A. MacNaughton, RN, BSN
Date Reviewed:09/19/02
Endocrinology, 1989, DeGroot et al.
Harrison's Principles of Inernal Medicine, 1998, Fauci et al.