Dermatomyositis is a very rare autoimmune condition that leads to muscle inflammation, pain and very classic skin rash. It can lead to swelling of your muscles, which can lead to pain and muscle weakness.
Dermatomyositis affects children and adults, but most commonly is found is patients aged 50-70 years old. Women are more commonly affected than men, and patients who have other autoimmune diseases such as rheumatoid arthritis or lupus may be at a higher risk to develop dermatomyositis.
The symptoms of dermatomyositis are split into two categories: muscle symptoms and skin symptoms. Since this disease affects both the muscles and your skin, it can lead to a large variety of symptoms.
Symptoms include:
The exact trigger or cause of dermatomyositis is unknown. However, there are a few known risk factors that increase your overall risk of the disease. Other than the factors stated above, the following can increase your risk of the disease:
Dermatomyositis is diagnosed with both physical exam findings and with blood and imaging tests. Your physician will start by taking a thorough history and doing a physical exam that focuses on muscle strength and ability. Often patients with dermatomyositis cannot stand up easily from chairs due to hip weakness and have issues with shoulder strength as well. This type of muscle weakness plus calcinosis or classic rashes on the eyelids may lead to your physician doing labs and imaging tests. Blood tests can be done to look for muscle inflammation and other autoimmune antibodies that are pathognomonic for dermatomyositis.
If imaging tests are needed for diagnosis, then certain tests can be completed to see if there is inflammation in your muscles.
Dermatomyositis is treated with both symptomatic support and with medications that calm down your immune system. Physical therapy can help you strengthen your muscles and learn how to best use the muscle strength that you have. Immunosuppressive drugs may also be used to help decrease the activity of your immune system to decrease your immune system attacking your muscles and your skin.
Dermatomyositis is part of a group of autoimmune muscle diseases that leads to muscle weakness and pain. Its key finding is that it also affects the skin. Fortunately, treatment is available and can help patients lead a healthy life.