Autoimmune disorders are conditions in which the immune system mistakenly attacks healthy cells in the body. Some of these diseases cause pain in the joints and muscles due to inflammation and swelling.
Autoimmune disorders that result in joint and muscle pain include rheumatoid arthritis and systemic lupus. According to the Women's Health Information Center, chronic fatigue syndrome and fibromyalgia are not considered autoimmune conditions, though symptoms are the same.
Autoimmune diseases may be triggered by the alteration of normal substances within the body (by drugs, virus or radiation) or by a malfunction of white blood cells, according to Merck.
Diagnosis of an autoimmune disorder is often made by the descriptions of your symptoms, blood tests and sometimes X-rays. Some diseases are difficult to diagnose and may only be determined as a result of other conditions being ruled out.
Treatment of autoimmune disorders include drugs that suppress the immune system, such as azathioprine, methotrexate and cyclophosphamide. Corticosteroids (such as Entocort and prednisone) also suppress the immune system and reduce inflammation in the joints.
There is no cure for autoimmune disorders that cause pain in joints and muscles. In order to manage the disease it is important to eat a nutritious, balanced diet, exercise regularly (though gently), get sufficient rest and reduce stress.