What is dermatomyositis?
Dermatomyositis is a rare autoimmune inflammatory disease. People with the condition experience a very distinctive skin rash, as well as muscle weakness and inflammation, and the tissues surrounding the muscles can be affected too. Although there isn’t currently a cure, the symptoms can usually be managed with medication, physiotherapy or another treatment.
It is not known what actually causes the condition to develop, but is one of three types of a condition called myositis (which means inflammation of the muscles).
Dermatomyositis can affect anyone, including children, but it is more common in women than men. The onset of the disease peaks between the ages of 5 to 15 in children and in adults, between their 40s to 60s.
If think you may have dermatomyositis, have a skin rash or are experiencing muscle weakness, should see a GP.
What are the symptoms of dermatomyositis?
The first noticeable symptom of dermatomyositis is the distinctive skin rash, which is blue-violet, or red in colour, and patchy. In some people this can develop quite suddenly, whilst in others, the rash can develop over time.
It most commonly appears on your knees, toes, elbows, chest, back, eyelids, nose, cheeks, knuckles or nail cuticles. The rash may be itchy and can sometimes be painful. Lumps of hard tissue and calcium can also develop under your skin, though this is more common in children and is called calcinosis, and can be removed with surgery.
Muscle weakness is the second most common symptom, but it may not develop till a few weeks, or even months after the rash. You may first notice it in your hips, thighs, shoulders and the tops of your arms and neck, and it will get worse over time.
You may also have other symptoms, which include:
- sore or painful muscles
- Swelling around the affected areas
- Weight loss (more so in adults than children)
- Night sweats
- Swallowing problems
- Breathing problems, such as shortness or breath or aspiration (where you breathe in food or liquids) - this is usually linked to the swallowing problems the condition can cause.
- Tiny red dots around your fingernails, which are leaky capillaries
You can also have the symptoms without experiencing any muscle weakness or pain, which is called amyopathic dermatomyositis.
Symptoms will vary from person to person - some people only have mild symptoms, while others can be severely affected by the condition.
The doctor will listen to the symptoms you have to see if they are associated with the condition. They will be able to assess any rash you have over video consultation. If they do believe you could have dermatomyositis, they will refer you for further testing.
The tests that the doctor may refer you for include:
- Muscle biopsy - A sample of muscle tissue may be examined for inflammation, or any other problems.
- Skin biopsy - A skin sample can be examined to look for changes caused by the disease
- Blood tests - to check the levels of auto-antibodies and muscle enzymes, which can mean that your muscles have been damaged
- Electromyography (EMG) - this can record your body’s electrical impulses, which control your muscles to let the specialist see if any of your muscles are showing signs of damage
- MRI - A magnetic resonance imaging scan can check your whole body for any muscle abnormalities and inflammation
- X-ray - the condition can be linked to lung damage, so you may have a chest X-ray to check for any signs of damage
Treatment for dermatomyositis
If you have a skin rash and/or muscle weakness then it is a good idea to see a doctor. If you are diagnosed with the condition, treatment can help you manage it, although there currently is not a cure. Dermatomyositis treatment may include:
Physiotherapy can help to preserve or even improve your muscle strength. When symptoms are severe, exercise is not recommended, though it is important to keep your muscles moving.
Corticosteroid medication (steroids)
This is the usual way dermatomyositis is treated. Creams can be applied to the rash, and tablets can be used to help with muscle weakness. Injections may also be used.
Corticosteroids reduce inflammation and suppress your immune system’s response, in-turn lowering the amount of the antibodies in your body. They can have side effects though, so should not be taken in high doses for a long period of time. You’ll usually be prescribed a higher dose to start with, and the doctor will then reduce the dose as quickly as they can to try to prevent any side effects occurring.
Intravenous immunoglobulin therapy
This is usually only used for severe cases of dermatomyositis where your breathing or swallowing is being affected.
Intravenous immunoglobulin therapy (IVIG) injects healthy antibodies into your body that block your own antibodies, which are attacking your muscles and skin. These good antibodies are administered through an IV, using donated blood.
Disease modifying anti rheumatic drugs
Disease modifying anti rheumatic drugs (DMARDs) can be used when muscle weakness is particularly bad. These reduce inflammation by suppressing your immune system.
If you and your dermatomyositis do not respond to immunosuppressants and steroid medications, then biological therapies may help. They block the process of inflammation in your body.
You may be prescribed one, or a number of these treatments depending on how dermatomyositis affects you. Usually, the condition responds well to treatment, though you may need to be on medication, or a treatment plan, for the rest of your life.
How can Push Doctor help?
You can see a GP about dermatomyositis at a time that suits you. Our doctors are available 7 days a week and can offer you the advice you may need. They can refer you to a specialist for further investigation or treatment. Book an appointment online today.