Dermatomyositis is swelling and redness of muscle and skin.
The exact cause of dermatomyositis is not known. It may be an autoimmune disorder. The immune system identifies and attacks viruses and harmful bacteria in your body. An autoimmune disorder means the immune system begins to attack normal healthy tissue.
A viral infection may trigger dermatomyositis.
Your chance of developing dermatomyositis is higher if you have a connective tissue disorder such as: Lupus erythematosusRheumatoid arthritisScleroderma
Diabetes mellitus in children
Dermatomyositis is also associated with certain genes.
Dermatomyositis may cause:
Skin changes such as:
Violet-colored, bumpy, or scaly skin rash, especially around the eyes, upper back, elbows, or knucklesItching, especially the scalpSensitivity to sunlightNail changesSkin nodules
problems such as:
Weakness especially in hips, thighs, arms or neckAching pain in legs, shoulder, arm, or neckTender musclesDifficulty swallowing and speakingAching and color changes in fingers, especially in cold temperaturesJoint painShortness of breath
Your doctor will ask about your symptoms and medical history. A physical exam will be done. You may be referred to a specialist for further evaluation.
Your bodily fluids and tissues may be tested. This can be done with: Blood tests
Your muscles may be tested. This can be done with
Images may be taken of your bodily structures. This can be done with: MRI
CAT scan (CT)
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There is no cure for dermatomyositis. Treatment is focused on managing the symptoms. Talk with your doctor about the best treatment plan for you. Treatment options include the following:
You may be referred to a physical therapist. The therapist will help improve or prevent the loss of muscle strength and function. It may include: Strength and flexibility exercisesGuidelines for a general exercise programTips to modify day to day activities if muscle weakness is affecting them
Corticosteroids can suppress your immune system. This will decrease inflammation in the muscle. Steroid medication can also be used on the skin to relieve skin symptoms. Corticosteroids can cause problems, like lower bone density. They can also increase infections. To lower these effects, you will be given the lowest dose needed to control your symptoms. You may also be asked to take supplements like calcium and vitamin D to improve your bone strength.
There are other medication options that can help to suppress the immune system. They may be used with or instead of the corticosteroids.
Immune globulin has healthy antibodies from several donors. These antibodies can block the unhealthy antibodies associated with dermatomyositis. It is given through an IV.
The infusion needs to be repeated every few weeks.
Regular exercise can help you develop and maintain muscle strength. Modify the program as needed to prevent irritating your condition. Check with your doctor and physical therapist for exercise guidelines. Rest when needed.
Your skin may also be more sensitive to the sun. Use sunscreen or cover your skin with clothes or a hat.
There are no known ways to prevent dermatomyositis.
Chung L, Genovese MC, et al. A pilot trial of rituximab in the treatment of patients with dermatomyositis.
Dermatomyositis. National Institute of Neurological Disorders and Stroke website. Available at:
http://www.ninds.nih.gov/disorders/dermatomyositis/dermatomyositis.htm. Updated August 26, 2011. Accessed August 7, 2013.
Idiopathic inflammatory myopathy. EBSCO Dynamed website. Available at:
http://www.ebscohost.com/dynamed/what.php. Updated April 7, 2013. Accessed August 7, 2013.
Dold S, Justiniano ME, et al. Treatment of early and refractory dermatomyositis with infliximab: a report of two cases.
Wong EH, Hui AC, et al. MRI in biopsy-negative dermatomyositis.
Last reviewed August 2013 by Michael Woods, MD
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.
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