A patient with muscle weakness

A 29 year old woman presented with symptoms of muscle weakness and difficulty swallowing. Physical examination showed swollen upper eyelids with a violaceous eruption (fig 1⇓). The dorsal side of her fingers was covered with an erythematous eruption. She also had bilateral symmetric purple discoloration of her skin in the area of the sternocleidomastoid muscle (fig 2⇓) and difficulty raising her arms above her head. A full blood cell count was normal. Creatinine kinase was raised at 1577 U/L (reference range 30-135). Fig 1 Fig 2 1. What is the diagnosis? 2. Does this disease have other skin specific manifestations? 3. Which laboratory tests can help confirm this diagnosis? 4. What should patients with this disease be screened for? 5. How would you treat this patient? ### 1. What is the diagnosis? #### Short answer Acute dermatomyositis (with heliotrope rash). #### Discussion Dermatomyositis is, together with polymyositis and inclusion body myositis, an idiopathic inflammatory myopathy. It is characterised by proximal muscle weakness and evidence of muscle inflammation. Dermatomyositis, unlike polymyositis, is associated with a variety of skin manifestations, including a heliotrope eruption. It is …