Juvenile dermatomyositis (JDM)

This material is intended to provide you with information about your child’s diagnosis of juvenile dermatomyositis (JDM).

What is JDM?

JDM is a condition which mainly affects the muscles and skin, but can affect other parts of the body. The word juvenile means this condition appears in childhood. Dermatomyositis means inflammation (itis) for example pain, redness, and swelling, of the skin (dermato) and muscle (myositis).

What causes JDM?

No one knows the exact cause of JDM. Lots of doctors and scientists are working to try and find out why some people get JDM. It may be a combination of genetic and environmental factors.

What are the signs and symptoms of JDM?

In most children with JDM symptoms include weakness and discomfort in the muscles which develops over a period of days, weeks or even months. Some children become uncharacteristically miserable and bad tempered. The muscle weakness tends to affect the large muscles around the trunk, hips and shoulders. You might notice your child has difficulty with walking, climbing the stairs, getting up from the floor or lifting their arms and they may tire quickly.

Some children have difficulty swallowing and their voice may sound different. Some children develop skin rashes or obvious reddening over the face (particularly cheeks and eyelids), upper chest, knuckles, elbows and knees.

How is JDM diagnosed?

Your child may need to have blood tests and other investigations such as an MRI scan of the muscles. They will be seen by a team of people including rheumatology consultants, specialists nurses, physiotherapists and or occupational therapists.

How is JDM treated?

There are treatments available for this condition. Usually treatment starts with steroids which can help dramatically. Some children may need other drugs which work by suppressing and reducing the inflammation. Nursing staff will talk you through the different medications and any side effects they have before they are started. Once treatment is working, your child can slowly reduce the steroid dose over many weeks. JDM is a chronic condition and relapses can occur.

Once discharged home, your child will need regular check-ups as an outpatient. This will usually include regular blood tests to monitor the effects of the medication and the activity of the disease. The treatment may change over time depending on how JDM is affecting your child. Physiotherapy is important to help strengthen weak muscles and prevent joints and muscles getting tight. You will meet your physiotherapist in hospital and you will see them most days. They will do an assessment to see which muscles are weak and this will be repeated at regular intervals to monitor progress. Physiotherapy will continue after your child has gone home. Your child will be given a home exercise programme and follow up appointments will be made either at Sheffield Children’s Hospital or at your local hospital. You may meet an occupational therapist (OT).

An OT will ensure your child can manage their daily tasks (such as dressing, bathing, attending school, writing). Your OT will advise you on when your child is ready to go back to school. It may be a few months before your child can return and usually your child will start going in for shorter days and then gradually increase time at school until he or she can manage full time. Some children may need a meeting at school prior to returning so that their teachers understand their needs

What does the future hold?

Fortunately most children will have a good improvement in response to treatment, however it is important to bear in mind that children will require close monitoring and regular visits to the rheumatologist for some time.