Myositis is a rare auto-immune disease in which the body’s immune system attacks its own skeletal muscles causing inflammation and progressive weakening of these muscles.
Skeletal muscles are voluntary muscles that we can consciously control to move different parts of our body. Myositis occurs both in children and adults.
The cause of myositis is not known. It is not passed on from the parent to the child, but the presence of certain genes can increase the risk for the disease. It is believed that an injury or infection may trigger the onset of the disease.
Initially myositis results in pain and weakness of hip and shoulder muscles making it difficult to do simple daily chores likes combing hair and climbing stairs. As the disease progresses it affects other muscles such as that of the throat and chest resulting in difficulty with swallowing, speaking and even breathing. Other general symptoms include fever, joint pain and swelling, and some forms of myositis also cause a skin rash.
There are four types of myositis:
- Polymyositis affects mainly the throat muscles causing difficulty in swallowing and speaking. It can occur both in adult and children.
- Dermatomyositis causes a distinct rash on the face, back, chest, elbow, knees and knuckles apart from affecting the various muscles of the body. It can occur both in adults and children.
- Inclusion body Myositis occurs mostly in people above 50 years of age. It is a progressive disease and slowly causes weakening of all voluntary muscles of the body.
- Juvenile Myositis usually occurs in children. It causes joint pain, skin rash and difficulty in swallowing.
There is no cure for the disease. Treatment only slows the progression of the disease and is aimed at reducing pain and inflammation. Treatment recommendations include rest, exercise, non-steroidal anti-inflammatory drugs (NSAID’s), corticosteroids and immune-suppressants.