Lymphocyte subsets and Langerhans' cells in toxic epidermal necrolysis. Report of a case.

Toxic epidermal necrolysis is a life-threatening disease, the pathogenesis of which remains largely unknown. Histologically, in addition to the characteristic epidermal alterations, there is a sparse mononuclear cell infiltrate in the dermis. The immunologic characteristics of this infiltrate are not well known. In a case of drug-induced toxic epidermal necrolysis with fatal outcome in a 48-year-old man, we demonstrated that the majority of the inflammatory cells were of helper/inducer T-lymphocyte subsets, having only a minority of cytotoxic/suppressor T-lymphocytes and rare cells with natural killer cell phenotype. The significance of these observations is discussed, with reference to the occurrence of lesions at epithelial sites bearing local networks of antigen-presenting cells (Langerhans' cells).