Dermatomyositis

Symptoms

The symptoms of dermatomyositis can appear at once or they can come on over time. The most common symptoms include:

• Skin changes. A violet-colored or dusky red rash appears, most often on the face and eyelids and on the knuckles, elbows, knees, chest and back. The rash may be harder to see on Black skin or brown skin.

  The rash is often the first sign of dermatomyositis. It may hurt and itch. There also may be small bumps on the hands, mainly near the knuckles.

  Children also may get white spots on their skin from calcium deposits, called calcinosis.

• Muscle weakness. Muscle weakness involves the muscles closest to the center of the body, called the trunk. This includes the muscles in the hips, thighs, shoulders, upper arms and neck. The weakness affects both the left and right sides of the body. It tends to get worse over time.

Some people with dermatomyositis have only the skin symptoms. But muscle weakness may start years later.

Causes

Experts don't know the exact cause of dermatomyositis. Having certain gene changes may make people more likely to get the condition.

Complications

Possible complications of dermatomyositis include:

• Trouble swallowing. The condition may affect the muscles in the tube that carries food from the throat to the stomach, called the esophagus. This can lead to trouble swallowing, called dysphagia. Trouble swallowing may cause weight loss and not getting enough nutrition.
• Aspiration pneumonia. Trouble swallowing also may cause breathing food or liquids, including saliva, into the lungs. This is called aspiration and can lead to pneumonia.
• Breathing problems. Dermatomyositis may affect the chest muscles. This can cause breathing issues, such as shortness of breath. If breathing is affected enough, it can cause failure of the system that allows breathing, called respiratory failure.
• Calcium deposits. These can happen in the muscles, skin and connective tissues as the disease gets worse. These deposits are more common in children with dermatomyositis.

Linked conditions

Dermatomyositis might cause other conditions or raise the risk of getting them, including:

• Raynaud's disease. This condition causes the fingers, toes, cheeks, nose and ears to turn pale, purple or red in response to cold temperatures or stress. Color changes may be harder to see on Black skin or brown skin. The condition also may cause numbness and tingling.
• Other diseases. Other autoimmune conditions, such as lupus, rheumatoid arthritis, scleroderma and Sjogren syndrome, can happen with dermatomyositis.
• Cardiovascular disease. Dermatomyositis may cause the muscular walls of the heart to become inflamed, called myocarditis. A small number of people who have dermatomyositis may get congestive heart failure and irregular heart rhythms, called arrythmias.
• Lung disease. A condition called interstitial lung disease may happen with dermatomyositis. Interstitial lung disease is a group of conditions that cause scarring of lung tissue. Called fibrosis, the scarring makes lung tissue stiff and thick. This makes it hard for the lungs to expand and fill with air.
• Cancer. Dermatomyositis in adults has been linked to a higher risk of getting certain types of cancer. Ask your healthcare professional what cancer screenings you may need.

Treatment

There's no cure for dermatomyositis. But treatment can improve muscle strength and help the muscles work better. Treatment also can help the skin.

Medications

Medicines used to treat dermatomyositis include:

• Corticosteroids. Medicines such as prednisone can manage dermatomyositis symptoms well. But using these medicines over time can cause serious side effects, including muscle weakness. So your healthcare professional tapers the dosage little by little.
• Corticosteroid-sparing agents. When used with a corticosteroid, these medicines may allow for a lower dosage and fewer side effects of the corticosteroid. The two most common medicines for dermatomyositis are azathioprine (Azasan, Imuran) and methotrexate (Trexall, Xatmep).
• Medicines for more-serious illness. Other medicines that treat dermatomyositis include mycophenolate mofetil (Cellcept, Myhibbin) and rituximab (Rituxan). These medicines can lessen the need for long-term corticosteroids.
• Intravenous immunoglobulin. Also called IVIg, this purified blood product has healthy antibodies from thousands of blood donors. These healthy antibodies can block the antibodies that attack muscle in dermatomyositis.

  IVIg involves getting the medicine through a vein, called an infusion. IVIg treatments may be used regularly or sometimes. The treatment mainly helps with trouble swallowing.

• Antimalarial medicines. For an ongoing rash, a healthcare professional might prescribe this type of medicine, such as hydroxychloroquine (Plaquenil, Sovuna).

Therapy

Depending on how serious the symptoms are, treatment might include:

• Physical therapy. A physical therapist can show you exercises to improve your strength and tell you what level of activity is right for you.
• Speech therapy. If dermatomyositis weakens muscles used for swallowing, speech therapy can help you learn how to work with the weakness.
• Nutrition help. Over time, dermatomyositis can make it harder to chew and swallow. A registered dietitian can teach you how to make easy-to-eat foods that give you enough nutrition.

Coping and support

Living with a chronic autoimmune disease can be a challenge. To help you cope, try the following:

• Know your illness. Read all you can about dermatomyositis and other muscle conditions. Talk to people who have a condition like yours. Ask your healthcare professional any questions that you have about your condition, diagnosis or treatment.
• Be a part of your medical team. Work with the healthcare professionals involved in your care. Follow your treatment plan, including physical therapy. Tell your healthcare team about any new symptoms you have.
• Know your limits. Ask for help when you need it. And let others know about the ways dermatomyositis limits you.
• Be active. Exercise can help you keep muscles strong. Ask your healthcare professional or physical therapist for a detailed plan before starting an exercise program.
• Rest when you're tired. Don't wait until you're worn out. Learn to pace yourself so that you keep your energy level, get done what you need to do and feel better mentally.
• Accept your feelings. Dealing with an ongoing illness may cause anger, sadness and other feelings. You might feel like your life is a challenge and that you're alone.

  Stay close to family and friends. Stick to your daily routine as best you can. Do things you enjoy. Many people find support groups helpful.