Juvenile dermatomyositis in children
Juvenile
dermatomyositis is a form of arthritis that occurs in children. This is a rare
condition that causes inflammation and swelling of the muscles and blood
vessels under the skin. It can also be called inflammatory myopathy.
Scientists don't know
exactly what causes this type of arthritis. This is an autoimmune disease,
which means that the immune system mistakenly attacks the muscle cells and
blood vessels of the skin.
Symptoms
The most common signs
of juvenile dermatomyositis are muscle pain, weakness, and rash. About half of
children with the disease have weak muscles, especially in muscles closer to
the trunk, hips, thighs, shoulders, and neck. The disease affects both sides of
the body and tends to get worse over time.
Your child may not
tell you that his muscles are weak. Here are some signs to look out for:
- She has a hard time getting out of a chair.
- She can't lift her arms above her head (if she's brushing her hair, for example).
- She turns over in bed slowly.
- She has trouble climbing stairs.
- She falls sometimes for no reason.
The rash may appear
with muscle weakness, or it may appear months later. Symptoms can be mild to
severe. The rash may look like this:
- A red, purple rash on his cheeks and eyelids
- A patchy rash on the skin around the nails, elbows, chest, back, and knees
- Redness or swelling near his fingernails
- Skin ulcers (open wounds on his skin)
- Sometimes, the rash may look like eczema.
Other symptoms of
juvenile dermatomyositis depend on which area of your child's body is
affected. They may include:
- Hard lumps of calcium under her skin (calcinosis)
- Joints that are strangely bent (contractures)
- Weak voice
- Hard time swallowing
- Fatigue, fever, and weight loss
- Problems breathing (which can be life threatening)
- Stomach aches
Diagnostics
If your child has a
rash or muscle weakness, make an appointment with the pediatrician. Early
diagnosis of juvenile dermatomyositis is important to prevent permanent muscle
damage.
Your child's doctor
will ask about their symptoms and medical history. Some tests can help diagnose
juvenile dermatomyositis or rule out other conditions. They understand:
- Blood tests to check for proteins associated with inflammation, or so-called autoantibodies, which are associated with juvenile dermatomyositis.
- Electromyography to measure the electrical activity of your child's muscles and find the location of the disease. Small patches are placed on your child's skin and wires connect them to a device that records the activities.
- Magnetic resonance imaging to detect early signs of inflammation and muscle swelling. It uses strong magnets and radio waves to create a detailed picture of your child's affected areas.
- Biopsy of the muscles to look for signs of inflammation or infection. A small piece of muscle tissue is removed for examination under a microscope.
- Careful examination of the nails and cuticles with a magnifying glass (capillaroscopy of the nail fold) to identify active signs of the disease.
Treatment
There is no cure for
juvenile dermatomyositis.
But early treatment
can help prevent irreversible health problems. Treatment includes medication,
physical therapy, and speech therapy, depending on your child's symptoms.
- Medications: Strong anti-inflammatory drugs called corticosteroids,
usually prednisone, are used primarily to relieve symptoms. Your child will
take them for a long time (sometimes years). They may act quickly, but often
have side effects, some of them serious. Long-term use of corticosteroids can
affect your child's bone growth and vision. Another drug called methotrexate is
often given with prednisone. Sometimes nonsteroidal drugs may be prescribed.
They include immunoglobulin IV, cyclosporine, azathioprine, tacrolimus,
hydroxychloroquine, and mycophenolate mofetil. For very severe symptoms,
anti-tumor necrosis factor drugs or rituximab may be used. Always ask your
child's doctor about expected side effects.
- Physical therapy: Your child's therapist will teach him stretching and
exercises to strengthen muscles and prevent weakness.
- Speech therapy: juvenile dermatomyositis can damage the muscles a child
uses to speak. Speech therapy can help.
- Dietary help: Muscle weakness in your child's tongue, throat, and
neck can make it difficult to chew and swallow food. Soft foods may be easier
to eat. A registered dietitian can show you how to develop a suitable and
balanced diet. More protein may be recommended to compensate for muscle damage.
If eating is especially difficult, your baby may need a feeding tube.
With proper
treatment, the signs of the disease may disappear (go into remission). But some
children have long-term symptoms that do not improve with treatment.
How can I help my child?
Juvenile
dermatomyositis is a lifelong disease. It's important to make sure your child
sticks to their treatment plan and stays as healthy as possible. Here are some
ways to help him with this:
- Make sure your child gets plenty of exercise. Physical activity maintains muscle strength and joint health. Exercise also helps maintain a healthy body weight.
- Use sunscreen. The sun's ultraviolet rays can make your child's rash worse. Choose one that protects against UV A and UV B rays. Wide-brimmed hats and sun protection clothing are also helpful.
- Talk to your child's teachers and school leaders about their illness. This is especially important because he may not appear sick.