A severe skin adverse drug reaction with skin detachment that can result in death. Mortality rates are 5% with SJS, 30-35% with TEN and 10-15% with transitional forms. Epidermal detachment may be extensive and to the entire skin surface. As in severe burns, fluid losses are massive, producing electrolyte imbalance.
SJS and TEN are variants of the same process. Super-infection, thermoregulation impairment, excessive energy expenditure, alteration of immunologic functions and hematologic abnormalities are usual systemic complications. Mucous membrane involvement (oropharynx, eyes, genitalia and anus) require attentive nursing care. The tracheobronchial epithelium, and less often gastrointestinal epithelium can be involved and cause high morbidity. Age, percentage of denuded skin, neutropenia, serum urea nitrogen level, and visceral involvement are prognostic factors.
Many TEN cases have occurred during treatment with high doses of corticosteroids for preexistent disease. The most extensive study of medication use and SJS-TEN mainly pointed to antibacterial sulfonamides, anticonvulsant agents, some nonsteroidal anti-inflammatory drugs and allopurinol. HIV infection dramatically increases the risk. A predisposing effect of autoimmune disorders, such as systemic lupus and an HLA-linked genetic susceptibility have been also suggested.