Dermatomyositis

This inflammatory myopathy is believed to be related to immune-mediated muscle damage.¹ An increased incidence of malignancy is associated with dermatomyositis (DM), especially in patients older than 50 years.²The characteristic cutaneous features of DM are heliotrope rash and Gottron papules. The rash is a dark, violaceous, erythematous discoloration usually distributed symmetrically over the periorbital skin (A). It may or may not be associated with edema. Gottron papules are firm, erythematous papules found over bony prominences, especially the metacarpophalangeal, proximal, and distal interphalangeal joints (B). They can precede clinically obvious muscle disease. Less characteristic skin lesions of DM include malar erythema, poikiloderma in a photosensitive distribution, violaceous erythema on the extensor surfaces, and periungual and cuticular changes. Patients may also exhibit periungual telangiectasia with hypertrophic changes of the cuticle and small infarcts.