Addison disease occurs when the adrenal glands are no longer able to produce certain hormones needed for life, such as cortisol and aldosterone.
What is going on in the body?
There are two adrenal glands in the body, one on top of each kidney. They produce two hormones: cortisol and aldosterone.
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.
- It helps maintain blood pressure, heart function, and blood vessel function.
- It helps slow the immune system's inflammation response.
- It helps balance the effects of insulin in breaking down glucose for energy.
- It helps control the metabolism of proteins, carbohydrates, and fats.
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 is a type of hormone called a mineralcorticoid. It helps with the following functions:
- maintains blood pressure
- maintains water and salt balance in the body by helping the kidneys hang on to sodium and get rid of potassium
What are the causes and risks of the disease?
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:
- an inherited syndrome called polyendocrine deficiency syndrome, type 1 or type 2
- tuberculosis, called TB
- chronic infections, mainly fungal infections
- cancer that has spread from somewhere else in the body
- surgical removal of the adrenal glands
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:
- surgical removal of the benign, known as noncancerous, tumors of the pituitary gland linked with Cushing disease. These tumors produce excess ACTH, and when they are removed, the body is unable to adapt quickly
- hypopituitarism, due to tumors, infections, loss of blood flow to the pituitary, radiation for pituitary tumors, or surgical removal of parts of the hypothalamus or the pituitary gland
What are the treatments for the disease?
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.
What are the side effects of the treatments?
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.
What happens after treatment for the disease?
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.
How is the disease monitored?
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.