Dermatomyositis and lichen planus-an association or manifestation?

Summary Two patients with dermatomyositis presented with violaceous lichenoid eruptions on the light exposed areas. Histology and direct immunofluorescence showed the typical features of lichen planus. The rash in dermatomyositis usually consists of a purplish‐red heliotrope erythema on the face, erythematous changes on the hands and backs of the fingers with diffuse redness and shining of the nail folds (Rowell, 1979). A pathognomonic sign in dermatomyositis is the Gottron papule, a violaceous flat‐topped lesion over the dorsal interphalangeal joints and occasionally a diffuse lichenoid eruption occurs which may be mistaken for lichen planus (Braverman, 1983). However, there have been no previous reports of the histology and immunofluorescence findings in these patients. Two cases are reported showing clinically a violaceous lichenoid eruption on the dorsal aspect of both hands with the histology and direct immunofluorescence typical of lichen planus. The association of lichen planus and dermatomyositis is discussed.