Myositis (my-o-SY-tis) is a rare type of autoimmune disease that inflames and weakens muscle fibers.
Autoimmune diseases occur when the body’s own immune system attacks itself.
In the case of myositis, the immune system attacks healthy muscle tissue, which results in inflammation, swelling, pain, and eventual weakness.
What autoimmune disease affects muscles?
Autoimmune myositis is a group of autoimmune rheumatic disorders that cause inflammation and weakness in the muscles (polymyositis) or in the skin and muscles (dermatomyositis).
What causes weak and painful muscles?
Other conditions that may cause muscle weakness include:
- herniated disc.
- chronic fatigue syndrome (CFS)
- hypotonia, a lack of muscle tone that’s usually present at birth.
- peripheral neuropathy, a type of nerve damage.
- neuralgia, or sharp burning or pain following the path of one or more nerves.
What are the signs and symptoms of polymyositis?
What are the symptoms of polymyositis?
- Muscle pain and stiffness.
- Muscle weakness, particularly in the belly (abdomen), shoulders, upper arms, and hips.
- Joint pain and stiffness.
- Trouble catching your breath.
- Problems with swallowing.
- Irregular heart rhythms, if the heart muscle becomes inflamed.
What triggers myositis?
Myositis refers to any condition causing inflammation in muscles. Weakness, swelling, and pain are the most common myositis symptoms. Myositis causes include infection, injury, autoimmune conditions, and drug side effects. Treatment of myositis varies according to the cause.