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Polymyositis and dermatomyositis

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What are polymyositis and dermatomyositis?

Myositis means an inflammation of the muscles. Polymyositis affects many muscles, especially around your shoulders, hips and thighs. Dermatomyositis causes muscle inflammation similar to polymyositis, but the symptoms also include a particular skin rash. Read more >

What are the symptoms of polymyositis and dermatomyositis?

Symptoms of polymyositis include:
  • weak and tired muscles
  • muscles that feel tender to the touch and painful
  • feeling generally unwell, weight loss and night sweats
When myositis occurs with a red/pink rash, it’s called dermatomyositis. The rash occurs on your upper eyelids, face and neck, and the backs of your hands and fingers. You may also notice swelling in the affected areas, which causes a characteristic puffiness and colouring around your eyes. Read more >

Who gets polymyositis and dermatomyositis?

Polymyositis and dermatomyositis are rare diseases, affecting only 6–8 people out of 100,000. They mostly affects adults, although children can be affected by a type of dermatomyositis called juvenile dermatomyositis. Read more >

What causes polymyositis and dermatomyositis?

Polymyositis and dermatomyositis are autoimmune diseases, but we don’t yet know why they happen. Read more >

What is the outlook for polymyositis and dermatomyositis?

Even severe cases of polymyositis and dermatomyositis respond to treatment, so the outlook is good. But your muscle strength may take longer to recover. Read more >

What are the possible complications of polymyositis and dermatomyositis?

Polymyositis and dermatomyositis can have some severe complications. It’s important to be aware of these and the symptoms they may cause. Read more >

How are polymyositis and dermatomyositis diagnosed?

The symptoms for polymyositis and dermatomyositis can be similar to many other conditions, so your doctor may base the diagnosis on:
  • an examination
  • blood tests
  • an electromyography (EMG) test
  • a muscle biopsy
  • a magnetic resonance imaging (MRI) scan of the muscles with the most symptoms
Read more >

What are the other types of myositis?

Other types of myositis include:
  • post-infectious reactive myositis
  • inclusion body myositis (IBM)
Read more >

What treatments are there for polymyositis and dermatomyositis?

Your doctor may recommend one or more of the following treatments for polymyositis and dermatomyositis: Read more >

Research and new developments for polymyositis and dermatomyositis

A study is looking at the effectiveness of steroids in various combinations with other drugs with the aim of finding the best combination of drugs for treating polymyositis and dermatomyositis. Read more >
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