Although not common I have seen about 4 or 5 since working in rheumatology. I have found that early diagnosis is essential to minimise muscle damage. If undiagnosed and treated with exercise it can do more damage initially when they are in active disease. Therefore corticosteroids are best to control the inflammation. They are usually given a second line drug to prevent further increase in inflammatory markers. Once they have been given steroids they can begin to exercise gently. I have had good success with hydrotherapy. It is unlikely you will recover full power, it depends on how much damage has occurred to the muscles affected. A muscle biopsy usually diagnoses the problem but it can mimic other rheumatic diseases like polymyalgia. Dermatomyositis presents with rashes on the face, hands, lower limb.

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