Dear Doctor: What can you tell me about lupus? Is it true that there are two different kinds? One of the skin, and one that affects the entire body?
Dear Reader: There are actually several types of lupus-related skin conditions. While some of these can affect the skin alone, many are related to systemic lupus erythematosus (SLE). This is the most common type of lupus and can affect the skin and any organ in the body. First recognized in the 19th century, SLE was initially thought to be a skin disorder because of its obvious external effects. It took many more years for physicians to realize that it was actually a systemic autoimmune disease with the ability to affect any organ in the body.
In the United States, estimated prevalence of the disease varies, but is generally regarded as slightly more than 1 in 1,000 people. In adults, lupus occurs more frequently in women than in men, with a female-to-male ratio of about 8-to-1. In the United States, it's more common among people of African, Asian and Hispanic ancestry, with African-Americans having nearly 2 1/2 times the likelihood of lupus compared to those of European ancestry.
Genetics are a significant risk factor for the disease. In a study among Latinos, if one sibling had SLE, the other sibling had a 29 times greater risk of developing lupus compared to the rest of the population. Certain medications also can increase the risk of lupus.
Lupus develops when the immune system's antibodies attack cell structures -- the nuclei and membranes -- and form immune complexes that circulate and deposit in different portions of the body. These immune complexes, made of antibodies attached to antigens, bring in white blood cells that release inflammatory chemicals, which damage the tissues further.
The disease is marked by cycles of flares and remissions. When the disease is flaring, or active, a person suffers from fatigue, muscle aches, joint pain and sometimes fever. He or she also may lose a considerable amount of weight.
Lupus affects the kidneys 50 percent of the time, which can lead to kidney dysfunction, and the gastrointestinal system 40 percent of the time, which can include the esophagus, the small or large intestine, the pancreas and the liver. Joint pain and arthritis are also common, and although lupus can affect any joint, the knees, wrists and fingers are most susceptible.
Lupus can also damage the heart and lungs, and the deposits of immune complexes can cause inflammation of blood vessels. In short, any part of the body can be affected, including the brain, eyes, blood cells, muscles, bone and skin.
People with systemic lupus most typically develop a type of rash that affects the face at the cheeks and nose, described as a "butterfly" rash. The rash is often exacerbated by sun exposure, and this may be the first sign of lupus, occurring months or years before other symptoms.
Some types of lupus-related skin conditions are not associated with systemic lupus. These lesions, commonly diagnosed with a biopsy, are often circular and plaquelike and can be located anywhere upon the body.
Treatment for these skin conditions includes non-steroidal immune-modulating creams and possibly immunosuppressant oral drugs; stronger immunosuppressant drugs are necessary for systemic lupus erythematosus.
With all types of lupus, treatment is focused on controlling symptoms. With SLE specifically, it will be a lifelong commitment.
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