The rare autoimmune disease juvenile dermatomyositis (JDM) affects children under 16 and causes inflammation and damage to the skin, muscles, and blood vessels. It can lead to serious complications, including infections, ulcers, calcinosis, and lung problems. However, there is no cure for JDM. It can be treated with medications, therapies, and lifestyle changes.
The exact cause of JDM is unknown, but it is believed to be triggered by environmental factors, such as viruses or bacteria, in children who have a genetic predisposition to develop autoimmune diseases. In autoimmune diseases, the immune system mistakenly attacks its own tissues rather than foreign invaders, causing inflammation and damage to the skin and muscles.
JDM is characterized by skin rashes and muscle weakness. Most commonly, these skin rashes appear on the face, eyelids, knuckles, elbows, knees, and ankles. They can be red or purple in color and scaly or bumpy in texture. As a result of muscle weakness in the neck, shoulders, hips, and thighs, a child may have difficulty climbing stairs, getting up from the floor, or swallowing. Other symptoms may include:
Fatigue and fever
Joint pain and swelling
Weight loss and poor appetite
Difficulty breathing and coughing
Abdominal pain and vomiting
Hard, white lumps under the skin (calcinosis)
Mouth sores and dental problems
There is no specific test for JDM, but the diagnosis is based on the child’s medical history, physical examination, and laboratory tests. Some of the tests that may be used to diagnose JDM are:
Blood tests: These can measure the levels of certain antibodies, enzymes, and inflammatory markers that indicate JDM. They can also check the function of the liver, kidneys, and other organs.
Urine tests: These can detect the presence of blood, protein, or calcium in the urine, which may indicate kidney damage or calcinosis.
Muscle biopsy: This involves taking a small sample of muscle tissue and examining it under a microscope. It can show signs of inflammation, damage, and vasculitis in the muscle fibers.
Skin biopsy: This involves taking a small sample of skin tissue and examining it under a microscope. It can show signs of inflammation, damage, and vasculitis in the skin layers.
Electromyography (EMG): This involves inserting a thin needle into a muscle and measuring the electrical activity. It can show signs of muscle weakness or damage.
Magnetic resonance imaging (MRI): This involves using a powerful magnet and radio waves to create images of the muscles and other tissues. It can show signs of inflammation, damage, and calcinosis in the muscles.
The treatment of JDM aims to reduce the inflammation, prevent the complications, and improve the quality of life of the child. The treatment may include:
These include corticosteroids, which suppress the immune system and reduce inflammation; immunosuppressants, which lower the activity of the immune system and prevent further damage; and antimalarials, which reduce calcinosis and improve skin rashes. A doctor must monitor medications for side effects, such as weight gain, infection, bone loss, or growth problems.
Exercises and stretching are used in physical therapy to maintain or improve muscle strength, flexibility, and function. They can also prevent muscle contractures, which are permanent shortenings of the muscles.
Occupational therapy involves activities and devices that help the child perform daily tasks, such as dressing, eating, and writing. It can also improve the child's self-esteem and independence.
Physiotherapy: This involves exercises and techniques that help the child improve their speech and swallowing skills, as well as prevent aspiration, which is the inhalation of food or liquids.
In order to prevent skin cancer, you need to avoid or limit exposure to the sun, which can worsen skin rashes. You also need to wear sunscreen, hats, sunglasses, and protective clothing.
Providing sufficient calories, protein, vitamins, and minerals for the child's growth and development is essential to preventing or treating malnutrition, anemia, or osteoporosis, which are common complications of JDM.
A surgical procedure can be used to remove or drain the calcinosis, which can cause pain, infection, or ulceration, as well as to correct muscle contractures, which can reduce joint movement and function.
There is no known way to prevent JDM, but some of the possible ways to reduce the risk or severity of the condition are:
Avoiding or treating the infections that may trigger JDM, such as colds, flu, or strep throat
Getting regular vaccinations to protect against the diseases that may trigger JDM, such as measles, mumps, rubella, or chickenpox
Seeking medical attention as soon as possible if the child develops any signs or symptoms of JDM, such as skin rashes, muscle weakness, or fever
Following the doctor’s advice on the medications, therapies, and lifestyle changes that can help treat JDM and prevent the complications
Having regular check-ups and tests to monitor the child’s condition and response to the treatment
