Lupus -- also known as systemic lupus erythematosus -- is a disease of the immune system. Normally, the immune system protects the body from infection. In lupus, however, the immune system inappropriately attacks tissues in various parts of the body. This abnormal activity leads to tissue damage and illness.
According to the Lupus Foundation of America, approximately 1.5 million people in the U.S. have lupus. People of African, Asian, and Native American descent are more likely to develop lupus than are Caucasians. Although it can occur in both men and women, 90% of people diagnosed with the disease are women. Women of childbearing age (14 to 45 years old) are most often affected and as many as 1 in 250 people may develop lupus.
What Are the Symptoms of Lupus?
The symptoms of lupus differ from one person to another. Some people have just a few symptoms, while others have many. In addition, there are many different symptoms of lupus because the disease can affect any part of the body. Some of the more common symptoms include:
Many people with active lupus feel ill in general and complain of fever, weight loss, and fatigue. People with lupus also develop specific problems when the immune system attacks a particular organ or area in the body. The following areas of the body can be affected by lupus:
Skin.Skin problems are a common feature of lupus. Some people with lupus have a red rash over their cheeks and the bridge of their nose -- called a "butterfly" or malar rash. Hair loss and mouth sores are also common. One particular type of lupus that generally affects only the skin is called "discoid lupus." With this type of lupus, the skin problems consist of large red, circular rashes that may scar. Skin rashes are usually aggravated by sunlight. A common lupus rash called subacute cutaneous lupus erythematosus is often worse after exposure to the sun. This type of rash can affect the arms, legs, and torso. An uncommon but serious form of lupus rash results in the development of large blisters and is called a "bullous" lupus rash.
Joints.Arthritis is very common in people with lupus. There may be pain, with or without swelling. Stiffness and pain may be particularly evident in the morning. Arthritis may be a problem for only a few days or weeks, or may be a permanent feature of the disease. Fortunately, the arthritis usually is not crippling.
Kidneys.Kidney involvement in people with lupus can be life threatening and may occur in up to half of those with lupus. Kidney problems are more common when someone also has other lupus symptoms, such as fatigue, arthritis, rash, fever, and weight loss. Less often, kidney disease may occur when there are no other symptoms of lupus.
Blood. Blood involvement can occur with or without other symptoms. People with lupus may have dangerous reductions in the number of red blood cells, white blood cells, or platelets (particles that help clot the blood).