Juvenile Dermatomyositis

Juvenile dermatomyositis (JDM) is an autoimmune disorder that affects blood supply to muscles, and causes muscle inflammation. If untreated, this inflammation can lead to muscle deterioration, muscle weakness and joint problems.

No one knows exactly what causes dermatomyositis in children. But many researchers believe that genetics, the immune system and environmental influences all play a role.

Juvenile dermatomyositis affects roughly 3,000 to 5,000 children in the U.S. Most cases of the condition occur in children ages 5 to 10.

The earliest sign of juvenile dermatomyositis is the gradual development of a skin rash. The rash might appear as a reddish-purple patch, or as a purple rash around the eyelids and cheeks.

Some children start experiencing muscle weakness at the same time as they develop the dermatomyositis rash. Other kids might not notice muscle weakness until days, weeks or even months after the initial rash. A child’s weakest muscles are typically those closest to the torso—for example, neck, shoulders, stomach, back and hips.

Common symptoms of juvenile dermatomyositis include:

• Fever ranging from 101 to 104 degrees.
• Hardened lumps or sheets of calcium (calcinosis) under the skin.
• Hoarse or weak-sounding voice.
• Muscle pain.
• Poor appetite.
• Stomach problems.
• Tiredness.
• Trouble lifting the head.
• Trouble swallowing.
• Weight loss.

Less common symptoms of juvenile dermatomyositis include:

• Vasculitic ulcers: These open sores in the skin or gastrointestinal tract result from inflamed blood vessels. They can extend deep into tissues, and can be very painful.
• Contractures: Sometimes juvenile dermatomyositis causes joint muscles to shorten (contract). Shortened muscles, in turn, lead to limited joint movement.

Your child might undergo the following tests to confirm a dermatomyositis diagnosis or check for other conditions:

• Laboratory tests: Laboratory work—such as blood tests—looks for signs of inflammation, including antibodies and muscle enzymes.
• Electromyography (EMG): An EMG measures nerve or muscle damage.
• Muscle biopsy: This test involves removing a small piece of muscle and examining it for microscopic signs of inflammation and vascular disruption.
• MRI: MRIs produce detailed images of inflamed muscle and blood vessels.

There is no single cure for juvenile dermatomyositis. But medicine, physical therapy, and regular exercise can help children who have JDM live typical, active lives. Treatment plans vary depending on the symptoms and complications dermatomyositis causes in each child.

If your child has dermatomyositis, treatment options might include:

If your child has juvenile dermatomyositis, the experts at Gillette Children’s Specialty Healthcare in rheumatology and neuromuscular conditions can offer specialized care to help manage symptoms and improve function.

Kids with JDM require full evaluations, correct diagnoses, and tailored treatments. As a regional referral center, Gillette treats hundreds of children annually who have juvenile dermatomyositis. We help kids improve function and mobility by reducing or eliminating the inflammation caused by juvenile dermatomyositis.

To give your child their best chance at leading a typical, active life we organize our treatment programs around the complex conditions that accompany juvenile dermatomyositis. Your child might receive care from experts in the following areas of service:

• Child life.
• Nutrition and feeding.
• Psychology.
• Radiology and imaging.
• Rehabilitation therapies, including physical therapy and occupational therapy.