Dermatomyositis

Key points

• an inflammatory disorder causing symmetrical, proximal muscle weakness and characteristic skin lesions
• may be idiopathic or associated with connective tissue disorders or underlying malignancy (typically ovarian, breast and lung cancer, found in 20-25% - more if patient older)
• polymyositis is a variant of the disease where skin manifestations are not prominent Skin features
• photosensitive
• macular rash over back and shoulder