If your doctor suspects that you have dermatomyositis, he or she might suggest some of the following tests:
- Blood analysis. A blood test will let your doctor know if you have elevated levels of muscle enzymes that can indicate muscle damage. A blood test can also detect autoantibodies associated with different symptoms of dermatomyositis, which can help in determining the best medication and treatment.
- Chest X-ray. This simple test can check for signs of the type of lung damage that sometimes occurs with dermatomyositis.
- Electromyography. A doctor with specialized training inserts a thin needle electrode through the skin into the muscle to be tested. Electrical activity is measured as you relax or tighten the muscle, and changes in the pattern of electrical activity can confirm a muscle disease. The doctor can determine which muscles are affected.
- MRI. A scanner creates cross-sectional images of your muscles from data generated by a powerful magnetic field and radio waves. Unlike a muscle biopsy, an MRI can assess inflammation over a large area of muscle.
- Skin or muscle biopsy. A small piece of skin or muscle is removed for laboratory analysis. A skin sample can help confirm the diagnosis of dermatomyositis. A muscle biopsy might reveal inflammation in your muscles or other problems, such as damage or infection. If the skin biopsy confirms the diagnosis, a muscle biopsy might not be necessary.
There's no cure for dermatomyositis, but treatment can improve your skin and your muscle strength and function.
Medications used to treat dermatomyositis include:
- Corticosteroids. Drugs such as prednisone (Rayos) can control dermatomyositis symptoms quickly. But prolonged use can have serious side effects. So your doctor, after prescribing a relatively high dose to control your symptoms, might gradually reduce the dose as your symptoms improve.
- Corticosteroid-sparing agents. When used with a corticosteroid, these drugs can decrease the dose and side effects of the corticosteroid. The two most common medications for dermatomyositis are azathioprine (Azasan, Imuran) and methotrexate (Trexall). Mycophenolate mofetil (Cellcept) is another medication used to treat dermatomyositis, particularly if the lungs are involved.
- Rituximab (Rituxan). More commonly used to treat rheumatoid arthritis, rituximab is an option if initial therapies don't control your symptoms.
- Antimalarial medications. For a persistent rash, your doctor might prescribe an antimalarial medication, such as hydroxychloroquine (Plaquenil).
- Sunscreens. Protecting your skin from sun exposure by applying sunscreen and wearing protective clothing and hats is important for managing the rash of dermatomyositis.
Depending on the severity of your symptoms, your doctor might suggest:
- Physical therapy. A physical therapist can show you exercises to help maintain and improve your strength and flexibility and advise you about an appropriate level of activity.
- Speech therapy. If your swallowing muscles are affected, speech therapy can help you learn how to compensate for those changes.
- Dietetic assessment. Later in the course of dermatomyositis, chewing and swallowing can become more difficult. A registered dietitian can teach you how to prepare easy-to-eat foods.
Surgical and other procedures
- Intravenous immunoglobulin (IVIg). IVIg is a purified blood product that contains healthy antibodies from thousands of blood donors. These antibodies can block the damaging antibodies that attack muscle and skin in dermatomyositis. Given as an infusion through a vein, IVIg treatments are expensive and might need to be repeated regularly for the effects to continue.
- Surgery. Surgery might be an option to remove painful calcium deposits and prevent recurrent skin infections.
Explore Mayo Clinic studies testing new treatments, interventions and tests as a means to prevent, detect, treat or manage this condition.
Lifestyle and home remedies
With dermatomyositis, areas affected by your rash are more sensitive to the sun. Wear protective clothing or high-protection sunscreen when you go outside.
Coping and support
Living with a chronic autoimmune disease can make you wonder whether you're up to the challenge. To help you cope, try the following:
- Know your illness. Read all you can about dermatomyositis and other muscle and autoimmune disorders. Talk to people who have a similar condition. Don't be afraid to ask your doctor questions concerning your illness, diagnosis or treatment plan.
- Be a part of your medical team. Consider yourself, your doctor and other medical experts involved in your care as a united front in the management of your disease. Following the treatment plan you agreed to is vital. Keep your doctor updated on any new signs or symptoms you develop.
- Get active. A regular exercise routine can help you maintain and build your muscle strength. Be sure to get a detailed plan and recommendations from your doctor or physical therapist before starting an exercise program.
- Rest when you're tired. Don't wait until you're exhausted. This will only set you back further as your body tries to recuperate. Learning to pace yourself can help you maintain a consistent level of energy, accomplish just as much and feel better emotionally.
- Acknowledge your emotions. Denial, anger and frustration are normal when dealing with dermatomyositis. Feelings of fear and isolation are common, so stay close to your family and friends. Try to maintain your daily routine as best you can and don't neglect doing things you enjoy. Many people find support groups helpful.
Preparing for your appointment
You're likely to first see your family doctor, who might refer you to a doctor who specializes in the treatment of arthritis and other diseases of the joints, muscles and bones (rheumatologist) and to a doctor who specializes skin diseases (dermatologist).
What you can do
Make a list that includes:
- Detailed descriptions of your symptoms and when they began
- Information about medical problems you've had, and those of your parents or siblings
- All the medications and dietary supplements you take and their doses
- Questions to ask the doctor
Take a family member or friend along, if possible, to help you remember the information you're given.
For dermatomyositis, questions to ask your doctor include:
- What is likely causing my symptoms?
- What are other possible causes?
- Are my symptoms likely to change over time?
- What tests might I need? Are special preparations required?
- Are treatments available for my condition? What treatments do you recommend?
- I have other medical conditions. How can I best manage them together?
- Do you have brochures or other printed material I can have? What websites do you recommend?
Don't hesitate to ask other questions.
What to expect from your doctor
Your doctor will likely ask you questions, such as:
- Did your condition develop gradually or come on suddenly?
- Are you easily fatigued during waking hours?
- Does your condition limit your activities?
- Has anyone in your family been diagnosed with a condition that affects the muscles?
- What, if anything, seems to improve your symptoms?
- What, if anything, appears to worsen your symptoms?