Parents pay a lot of attention to the skin of their child and, certainly, the skin exam is a valuable tool for the vigilant clinician (ex, Cap Refill , Petechiae below Nipple Line , Leukemia , RMSF ). That being said, the majority of pediatric rashes (See Peds Rash ) that present to the ED are often met with a combination of disdain and fear: “This looks like nothing, but is it something?” or “This looks awful, but is it a big deal?” One of the concerning characteristics is the target lesion , but not all target lesions are created equal. Let us take a minute to digest a morsel on Erythema Multiforme (EM) .
Similarities in clinical and histopathologic findings have led to controversy over the distinction between EM and Stevens-Johnson syndrome (SJS), an often drug-induced disorder that may present with cutaneous targetoid lesions and mucosal erosions. However, there is suggestive evidence that EM with mucous membrane involvement and SJS are different diseases with distinct causes [ 1 ]. The term erythema multiforme major should not be used to refer to SJS. (See "Stevens-Johnson syndrome and toxic epidermal necrolysis: Pathogenesis, clinical manifestations, and diagnosis" .)