The full name for lupus erythematosus
is actually systemic lupus erythematosus meaning that the the disease by its very nature affects more than one area of the body i. e. it is systemic. In fact, part of the usual diagnostic criteria are that multiple sights are affected. So not only can multiple muscle sites be affected such as the arms and legs, but frequently the skin, kidneys, heart, nervous system, GI tract and the blood. The overall course of the disease is usually determined by the extent of kidney involvement, with worsening renal functioning portending a worse prognosis.
Depending on how severe your disease you may experience involvement of many organ systems may become involved over the course of your life. Despite, this not everyone has involvement of all the organ systems listed above. About 4 out 5 people will have involvement of the skin with slightly more having muscle involvement as you do. The same amount typically have kidney involvement, and a much smaller percentage, 1 out of 3 have GI involvement. Finally, half will have involvement of the nervous system. To prevent these complications it is important to be under the medical care of a physician trained to treat lupus. A rheumatologist
can discuss the best ways to treat your symptoms and answer more of your questions. Good luck!