[Stevens-Johnson syndrome and toxic epidermal necrolysis--updates and innovations].

Stevens-Johnson Syndrome (SJS) and toxic epidermal necrolysis (TEN) are rare severe cutaneous adverse reactions, usually induced by drugs. The reactions, which are characterized by extensive necrosis and detachment of the epidermis, followed by erosions of the skin and mucous membranes, are associated with high rates of mortality. There is growing evidence that SJS and TEN are a single disease with common causes and mechanisms. The present article summarizes recent updates and innovations related to the etiology, pathogenesis, genetic background, prognosis and treatment of these reactions. Among high-risk drugs associated with SJS/TEN, allopurinol is the most common cause of SJS/TEN in Europe and Israel. The prognosis of SJS/TEN can be predicted by a scoring system based on seven clinical and laboratory parameters. Founded on the genetic background of SJS/TEN, predictive tests can be used prior to starting high-risk medications. Treatment is still controversial, and further controlled studies are necessary.