Dermatomyositis is a serious illness that in rare cases can be fatal. It’s important to get diagnosed and start treatment as early as possible. While there is no cure for dermatomyositis, symptoms can often be managed with long-term (sometimes life-long) medications and physical therapy.
Dermatomyositis is a rare disease that causes muscle weakness and rashes on your skin. It’s a form of myopathy. It can also cause severe symptoms that affect your ability to breathe and swallow.
Dermatomyositis is a form of polymyositis that affects your skin in addition to your muscles.
See your provider right away if you experience any symptoms of dermatomyositis. Some cases take months to develop, but dermatomyositis can develop quickly. The sooner you begin treatment, the more likely it is you can avoid having severe complications.
In rare cases, dermatomyositis can be fatal, especially in the first year after symptoms start. It can also increase your risk of developing certain kinds of cancer.
Dermatomyositis is similar to lupus and other autoimmune diseases. However, experts aren’t sure what causes dermatomyositis, so it’s not classified as an autoimmune condition.
If you have lupus, you might experience joint pain, skin sensitivities and rashes, and issues with your internal organs (brain, lungs, kidneys and heart). Many of your symptoms might come and go in waves — often called flare-ups.
Dermatomyositis causes muscle weakness and degeneration (tissue death) and a rash on your skin. It’s diagnosed with blood tests, biopsies and imaging tests.
Both dermatomyositis and lupus need diagnosed and treated as soon as possible. Visit your provider right away if notice any new symptoms.
Anyone can be affected by dermatomyositis, but some groups of people are more likely to develop it, including:
Dermatomyositis is very rare. Around 1 in every 100,000 people develop it each year.
Dermatomyositis could affect your body for the rest of your life.
If it damages your muscles badly enough you might lose the ability to move or use a part of your body the way you used to. This usually takes years to develop, but some people experience severe muscle weakness earlier than others.
Dermatomyositis has also been found to increase your risk of developing certain types of cancer.
Around 15% of people with dermatomyositis develop cancer later in their life. Some of the most common cancers people with dermatomyositis develop include:
Talk to your healthcare provider about your cancer risk and any screenings you need.
The most common symptoms of dermatomyositis are muscle weakness and a rash on your skin.
Some people notice muscle weakness and a rash around the same time. You might have one symptom for weeks, months or even years without the other.
Muscle weakness might make it hard for you to do common motions, including:
Dermatomyositis may cause a rash on your skin (especially on parts of your body exposed to the sun). Areas with a rash will be discolored and might be swollen. The most common locations include:
Other symptoms of dermatomyositis include:
Some people (especially kids) diagnosed with dermatomyositis grow out of it and never have symptoms again. However, 80% of cases are chronic (they come back over time) and cause lifelong symptoms.
Experts aren’t certain what causes dermatomyositis, but a few causes might include:
Dermatomyositis is usually diagnosed with blood tests and biopsies of your skin and muscles.
Your provider will test your blood for:
You might need one of a few imaging tests. Your provider will use these to evaluate your muscles, nerves, lungs and other organs. These tests can help them determine if your symptoms are caused by dermatomyositis or another issue. The most common imaging tests used to diagnose dermatomyositis include:
In some cases, your provider may request an electromyography (EMG). This test measures electrical activity in response to muscle or nerve stimulation.
Dermatomyositis treatments include:
Which treatments you need depends on where you’re having symptoms, and how severe they are. Talk to your provider about what to expect and when you’ll need certain treatments.
Managing your dermatomyositis symptoms will likely be a long-term process — possibly for the rest of your life.
If you have dermatomyositis, it’s important to see your healthcare provider regularly. They’ll need to monitor your symptoms and make sure your condition isn’t spreading or getting more severe.
It might take a few months for your symptoms to improve after you start treatment. Most people living with dermatomyositis feel better as they regain their original levels of muscle strength after treatment.
How long it takes you to feel better depends on which treatments you need, which symptoms you’re experiencing and how severe they are.
Talk to your provider about what to expect and when you should notice your symptoms getting better.
There’s no known way to prevent dermatomyositis. Because experts don’t know what causes it, there’s nothing you can do to prevent it.
There’s no cure for dermatomyositis. You should expect to manage your symptoms for the rest of your life.
Even with treatment, 80% of people have chronic dermatomyositis (sometimes referred to as polycyclic dermatomyositis). Your symptoms might come and go in waves throughout your life. Visit your provider right away as soon as you notice the signs of a symptom flare up.
Two-thirds of people living with dermatomyositis develop a physical disability because of the damage to their muscles.
Dermatomyositis is fatal for approximately 5% of people diagnosed with it. This is especially true in the first year after being diagnosed. But, about 20% of people with dermatomyositis go into long-term remission.
Some symptoms and other factors can increase your risk of dying, including if you:
Visit your provider right away if you notice new weakness in your muscles, especially if you have a rash on your skin around the same time. The sooner dermatomyositis is diagnosed, the faster you can start treatment. This can decrease your chances of experiencing severe symptoms and other complications.
Ask your provider how often you should schedule follow-up visits so they can track your symptoms and any changes in your muscles or on your skin.
A note from Cleveland Clinic
Being diagnosed with dermatomyositis can be extremely scary. Knowing you have a condition that will affect you for the rest of your life – especially one that can be fatal — is a huge shock. Take every day one step at a time. The sooner you’re diagnosed, the sooner you can begin treatment.
Talk to your provider about planning out your treatment and symptom management journey. They’ll help you understand what’s coming next and how to prepare for any changes you’ll need to make if the dermatomyositis causes more severe symptoms.
Last reviewed by a Cleveland Clinic medical professional on 05/11/2022.
Learn more about our editorial process.