There are certain skin characteristics of Addison disease. Skin changes may appear along with symptoms such as fatigue, weight loss, and weakness.
About Addison Disease
Addison disease is an endocrine disorder. The endocrine system involves the production and regulation of the many different hormones in the body. Two important ones, cortisol and aldosterone, are affected in Addison disease.
- Cortisol. Cortisol is produced by the adrenal glands. These triangle-shaped glands sit just above the kidneys. Cortisol is a very important hormone in the body. It helps maintain blood pressure, so that the blood can carry oxygen throughout the body. It also helps control the immune system. It's involved in metabolism, the processing of fats, proteins, and carbohydrates. And it helps keep you feeling awake and alert.
- Aldosterone. Aldosterone is also involved in maintaining blood pressure. It's part of the system that regulates salt and water balance and also helps maintain the correct level of potassium. Potassium balance is important to keep the heart working properly.
Causes of Addison Disease
Addison disease can occur when the adrenal glands themselves fail, or when the pituitary stops sending the right signals to the adrenal glands.
Primary Adrenal Insufficiency
Primary adrenal insufficiency involves the destruction of the adrenal glands. Both aldosterone and cortisol production fail. The adrenals can be damaged by the body's own immune system, by tuberculosis or other infection, or for other, less common reasons including cancer.
Secondary Adrenal Insufficiency
Secondary adrenal insufficiency happens when the pituitary fails to signal the adrenals to produce cortisol. It can happen when someone who has been taking artificial steroids, such as prednisone, suddenly stops. It can also be caused by other problems including tumors or infections in the pituitary gland, loss of blood flow to that gland, or surgical removal of the pituitary.
Addison disease can seem to appear suddenly, when an illness or accident puts stress on the body and causes an "Addisonian crisis." There may be a sudden drop in blood pressure, severe vomiting and diarrhea, pain in the lower back, legs, or abdomen, fainting, or other frightening symptoms. A person with Addisonian crisis needs medical help right away.
Before a crisis occurs, however, symptoms tend to come on gradually. There may be chronic fatigue, poor appetite, weight loss, weakness, and cravings for salt. Low blood pressure can lead to dizziness on standing. And many people have nausea, vomiting, or diarrhea.
Skin Characteristics of Addison Disease
The skin changes tend to appear gradually, too. The skin characteristics of Addison disease are called "hyperpigmentation," meaning that the skin becomes more pigmented, or darker, than normal. It may look like a deep tan, but it covers both sun-exposed skin and skin that wouldn't normally need sunscreen. Most, but not all, people with Addison disease will have skin manifestations.
Skin changes are most prominent on
- Skin folds, such as the armpits or groin
- Pressure points, like the backs of the elbows, knees, or toes
- Mucous membranes, such as the inside of the cheeks and the gums
Why Skin Changes Happen
The skin changes are due to overproduction of a substance called corticotropin, which the pituitary makes to try to stimulate the adrenal glands. When the adrenal glands are working, a feedback signal tells the pituitary to stop making corticotropin. But if there's no feedback signal because the adrenals aren't working, the pituitary makes more and more corticotropin. Corticotropin also happens to stimulate the production of melanin, which causes darkening of the skin.
In addition to skin discoloration, women with primary Addison disease may lose their pubic and underarm hair. This is because androgens, the hormones responsible for that hair growth, are made in the adrenals. The hair loss does not happen in men because their testes make androgens as well.
Making the Diagnosis
The skin characteristics of Addison disease won't usually appear alone. There are other diseases, including vitiligo, diabetes, melasma, and even cancer (skin cancer as well as other types), that can cause discoloration of the skin.
If your doctor is concerned that you might have a problem with your adrenal glands or pituitary, he or she will do some blood tests to find out. You may also need a CT scan or MRI.
Treatment for the skin characteristics of Addison disease is the same as the treatment for the disease itself. It involves replacing the missing hormones, usually in the form of pills. Extra medicine is needed when the body is under physical stress, such as during surgery. Addisonian crisis requires emergency treatment in a hospital.