Target lesions on the lips: Childhood herpes simplex associated with erythema multiforme mimics Stevens-Johnson syndrome

Erythema multiforme and Stevens-Johnson syndrome are both characterized by areas of epithelial necrosis. An important clinical feature that distinguishes the two is the extensive mucosal necrosis in Steven-Johnson syndrome but not in erythema multiforme. Because significant and serious complications may develop with Stevens-Johnson syndrome and not with erythema mutiforme, it is important to differentiate between the conditions. We describe three boys with herpes simplex virus–associated erythema multiforme who had severe necrosis of the lips develop and were initially diagnosed with Stevens-Johnson syndrome. The lip lesions were large target lesions of erythema multiforme rather than the extensive necrosis seen in Stevens-Johnson syndrome and all three had a benign course. (J Am Acad Dermatol 1997;37:848-50.)