Myositis is a disease associated with inflammation of the muscles. It is often associated with severe muscle weakness. Myositis can also affect other organ systems including the skin, joints, lungs, heart, and gastrointestinal system. It is a chronic disease and can last a long time. The most common forms of myositis are polymyositis, dermatomyositis and inclusion body myositis.
Myositis is an autoimmune disease. This means that the body's immune system does not behave normally. Instead of only fighting infections such as bacteria and viruses, the body's own immune system attacks itself. With myositis, the immune system may attack specific muscles resulting in muscle damage and destruction. The immune system may also attack other organs such as the lungs, skin, and joints.
This information has been approved by Aryeh Fischer, MD (April 2008).
