There is no cure for JDM. However, there are effective treatments that can reduce or eliminate the symptoms and allow people with JDM to lead active, healthy lives.
The goals of any treatment program for JDM are to control muscle inflammation and damage, maintain and improve muscle strength and function, relieve pain, control or prevent other symptoms, and help the child and the family learn to live with the illness.
To reach these goals, doctors work with families to find a treatment plan that works best for them. Treatment usually includes medication, physical therapy, and education. As your child's symptoms change, the treatment plan may also be changed. Some common drug therapies include:
Prednisone is the most commonly used drug in the group of medications called steroids, corticosteroids, or glucocorticoids. Other drugs in this group are Solumedrol or Prednisolone. Prednisone (or one of the other steroids) is the first treatment for children with JDM in most cases. Prednisone works quickly to control inflammation in the muscles, joints, and skin.
This drug is similar to cortisone, a hormone produced naturally in the body. At first, high doses of this drug are given until your child's muscle enzyme tests and strength improve. As your child gets better, the dose will be gradually reduced. In most cases children will remain on prednisone for at least two years.
Side effects depend on both the dose used and the length of therapy. Common side effects include weight gain, increased appetite, mood changes, increased risk for infections and facial swelling. Prednisone suppresses the immune system which is important in suppressing the inflammation but also increases the risk for infection. The degree of immune suppression is related to the dose. Over a long period of time, the drug can also cause decreased calcium content in the bones, cataracts, high blood pressure, and slowed growth rate. The doctor will lower the dose as soon as possible to lessen the side effects, while keeping the disease under control.
For almost all patients with JDM (unless there is a specific reason in a patient that it should not be used), methotrexate is started at the same time or very soon after prednisone. To help control the disease and to allow for fewer steroids to be used, methotrexate is often used. Methotrexate also suppresses the immune system. Methotrexate is also used to treat cancer but in much higher doses. Methotrexate has been used in the treatment of children with JDM and other rheumatic disease for over 30 years.
The effect in the body (both in the way that it affects the immune system as well as side effects) of methotrexate, in the doses used for treatment of children with JDM, is much milder than that seen in treatment of cancer. The doctor will use the lowest dose possible and will usually use it in combination with prednisone. Methotrexate can be given as a pill or by injection. It is given once a week.
Common side effects include nausea, feeling tired for about 12-24 hours after the dose (20-30 percent of patients) and mouth sores (5-10 percent of patients). Folic acid is a vitamin that can decrease the frequency and severity of these side effects. Less common side effects include increased liver enzymes and an increased risk of getting infections.
Hydroxychloroquine (brand name Plaquenil)
Hydroxychloroquine is a drug that is often used to treat the rash in children with JDM. The drug is given as a pill, usually once a day, and is given in combination with other drugs that control the other symptoms in children with JDM.
Hydroxychloroquine is generally tolerated very well. Some children will develop stomach upset. About 1 in every 3,000-5,000 people who take hydroxychloroquine will accumulate pigment in the retina of the eye. If this is allowed to progress, it could interfere with a person's vision. For this reason, an ophthalmologist (eye doctor) needs to check your child's eyes every 12 months while your child is taking hydroxychloroquine. If the eye doctor detects any pigment accumulation, the hydroxychloroquine will be stopped before any visual problems develop.
Cyclosporine (brand names Neoral or Sandimmune)
If prednisone and methotrexate don't fully control your child's JDM, your doctor may use cyclosporine. This is another type of immune suppressive drug that was originally developed for organ transplantation. Cyclosporine, in combination with methotrexate, can help better control the inflammation so that lower prednisone doses can be used with decreased risk for repeat episodes of disease.
Side effects that may occur include extra hair growth on the face and arms, swelling of gums, and high blood pressure.
Intravenous Immunoglobulin (IVIG)
IVIG is a blood-derived product that has been used in the treatment of children with JDM. IVIG consists of purified antibodies which are proteins that the body's immune system uses to fight infection. The mechanism of action is unclear, but IVIG has been shown to slow down the inflammatory process. IVIG is given through a needle into a vein (intravenous or IV) in the hospital usually once a month.
Side effects like headache, fever, and vomiting can occur, but they are usually prevented by pretreating with Tylenol, Benadryl, and sometimes the addition of a steroid.
Mycophenolate Mofetil (Cellcept)
Cellcept is a medication that is becoming increasingly used to treat severe disease that is not adequately controlled by the medications listed above. Cellcept is a powerful immune suppressive drug that is also used to treat severe lupus and other autoimmune diseases. It comes as a capsule, pill, or liquid and is taken twice a day.
Side effects include nausea, abdominal pain and increased risk of infection. While taking this medication, your child’s doctor will frequently monitor blood cell counts to make sure the risk of infection does not become too great. This medicine can often be very effective in allowing for lower prednisone doses.