Lupus is a type of immune system disorder known as an autoimmune disease. In autoimmune diseases, the body harms its own healthy cells and tissues. This leads to inflammation and damage of various body tissues. Lupus can affect many parts of the body, including the joints, skin, kidneys, heart, lungs, blood vessels, and brain. Although people with the disease may have many different symptoms, some of the most common ones include extreme fatigue, painful or swollen joints (arthritis), unexplained fever, skin rashes, and kidney problems. Lupus is also known as a rheumatic disease. The rheumatic diseases are a group of disorders that cause aches, pain, and stiffness in the joints, muscles, and bones.

At present, there is no cure for lupus. However, the symptoms of lupus can be controlled with appropriate treatment, and most people with the disease can lead active, healthy lives. Lupus is characterized by periods of illness, called flares, and periods of wellness, or remission. Understanding how to prevent flares and how to treat them when they do occur helps people with lupus maintain better health. Intense research is underway and scientists funded by the NIH are continuing to make great strides in understanding the disease, which ultimately may lead to a cure.

Two of the questions researchers are studying are who gets lupus and why. We know that many more women than men have lupus. Lupus is three times more common in black women than in white women and is also more common in women of Hispanic, Asian, and Native American descent. In addition, lupus can run in families, but the risk that a child or a brother or sister of a patient also will have lupus is still quite low. It is difficult to estimate how many people in the United States have the disease because its symptoms vary widely and its onset is often hard to pinpoint.

Although "lupus" is used as a broad term, there actually are several kinds of lupus:

Systemic lupus erythematosus (SLE), which is the form of the disease that most people are referring to when they say "lupus." The word "systemic" means the disease can affect many parts of the body. The symptoms of SLE may be mild or serious. Although SLE usually first affects people between the ages of 15 and 45 years, it can occur in childhood or later in life as well. This booklet focuses on SLE.

Discoid lupus erythematosus primarily affects the skin. A red, raised rash may appear on the face, scalp, or elsewhere. The raised areas may become thick and scaly. The rash may last for days or years and may recur. A small percentage of people with discoid lupus later develop SLE.

Drug-induced lupus refers to a form of lupus caused by medication. It causes some symptoms similar to those of SLE (arthritis, rash, fever, and chest pain, but not kidney disease) that go away when the drug is stopped. Common medications that may cause drug-induced lupus include hydralazine (Apresoline), procainamide (Procan, Pronestyl), methyldopa (Aldomet), quinidine (Quinaglute), isoniazid (INH), and some anti-seizure medications such as phenytoin (Dilantin) or carbamazepine (Tegretol).

Neonatal lupus can affect some newborn babies of women with SLE or certain other immune system disorders. Babies with neonatal lupus may have a serious heart defect. Other affected babies may have a skin rash, liver abnormalities, or low blood counts. Physicians can now identify most at-risk SLE patients, allowing for prompt treatment of the infant at birth. Neonatal lupus is very rare, and most infants of mothers with SLE are entirely healthy.

SOURCE: National Institutes of Health National Institute of Arthritis and Musculoskeletal  and Skin Diseases