Lichen planus presenting with erythema-multiforme-like bullous lesions in a patient with systemic scleroderma

A patient with systemic scleroderma is described who developed a cutaneous eruption of papules and vesicobullae. Over time, the latter turned into papules. The histopathological and immunofluorescence features of the papular lesions were unequivocally those of lichen planus, while those of the bullous lesions reminded of erythema multiforme. Histologically, erythema multiforme shares common features with lichenoid reactions, such as necrotic keratinocytes. Our case suggests that erythema multiforme and lichen planus may coexist or succeed each other as different stereotype immune reactions against the same antigen(s) within the epidermis.