CUTANEOUS DRUG ERUPTIONS WITH EPIDERMAL NECROSIS - A DISCUSSION OF PATHOPHYSIOLOGIC AND COMPARATIVE ASPECTS

Cutaneous drug eruptions occur unpredictably and intermittently in humans and animals.1,2 The spectrum of reactions manifested vary from a mild rash to sudden death. A wide variety of descriptive classifications are used to list drug eruptions, dependent on the clinical and histopathologic changes. The discussion here is restricted to that group which manifests clinically as erythema and vesiculation and histologically features epidermal necrosis. Unraveling the secrets of drug-induced epidermal necrosis potentially holds the key to many other idiopathic skin disorders that seem to share a similar pathogenesis. Using the drug-induced model to study the pathogenesis means that the initiating cause is at least known. Some aspects of the immunology are similar to graft-versushost reaction, thus providing more of an insight; however, the current state of knowledge is imperfect and, as a consequence, the treatment of these diseases is unsatisfactory. The diseases for which drug-induced epidermal necrosis is a central feature are fixed drug eruption, drug-induced erythema multiforme (EM), and drug-induced toxic epidermal necrosis (TEN). The human diseases that share features of epidermal necrosis for which an animal drug model may help unravel the mysteries include lichen planus, non-drug-induced EM and TEN, regressing warts and epithelial tumors, graft-versus-host reaction, lupus erythematosus, dermatomyositis, AIDS interface dermatitis, some postviral diseases, and, in animals, some parasitic diseases, including self-curing canine demodecosis. © 1994.