Erythema multiforme, Stevens–Johnson syndrome and toxic epidermal necrolysis: a comparative review

Abstract

(1) Histopathological lesions do not reliably differentiate EM, SJS and TEN. (2) A multicentre study to develop a consensus set of clinical criteria for EM and SJS/TEN in animals is overdue. (3) No adjunctive therapies, including intravenous immunoglobulin and ciclosporin, have met evidence-based standards.

Presumed phenobarbital-induced Stevens–Johnson syndrome in a 4-year-old female Great Dane

“…The present case had only oral mucosal involvement. Although this is present in the majority of SJS cases, and has been reported as one of the criteria to diagnose SJS, mucosal involvement is no longer required to make the diagnosis of SJS (BastujiGarin et al 1993;Yager 2014). The dermatopathological changes reflected a cytotoxic lymphocyte response against altered keratinocytes, as can also be seen in EM.…”

“…For many years, the position in human dermatology has been that EM, SJS and TEN occupy a spectrum, with EM at the milder end and TEN at the severe extremity. The current position, however, is that EM is a separate disease, mostly triggered by infection with herpes simplex virus (Yager 2014). In contrast, SJS and TEN represent a spectrum of largely drug-induced disease.…”

“…In contrast, SJS and TEN represent a spectrum of largely drug-induced disease. In veterinary medicine, confusion abounds around EM, SJS and TEN, still representing EM as a milder form of SJS/TEN as there are no universally agreements upon clinical criteria for EM in animals (Swartz et al 2013;Yager 2014). In human dermatology, SJS can be distinguished from EM clinically as the lesions in SJS are almost always flat compared to raised lesions in EM (Bastuji-Garin et al 1993).…”

“…However, the keratinocyte cell death was more extensive than in classical EM, and there was some epidermal detachment present. However, it is not possible to differentiate accurately between EM, SJS and TEN using histological criteria alone (Bastuji-Garin et al 1993;Yager 2014).…”

“…Indeed, epidermal detachment, as seen in this case is a hallmark of SJS. The extent of the epidermal detachment on the body surface is the main criterium to differentiate SJS from TEN (Yager 2014;Banovic et al 2015). SJS typically has epidermal detachment of less than 10% of the body surface, whilst TEN presents with epidermal detachment of more than 30% of the body surface.…”