T-Cell Subsets in Drug-Induced Toxic Epidermal Necrolysis

Abstract

A patient with bromisovalum-induced toxic epidermal necrolysis showed pronounced delayed hypersensitivity to bromisovalum by patch testing. Biopsy specimens from the cutaneous lesion and the site of the positive patch test reaction were analyzed and compared immunohistologically. The findings were similar: most of the mononuclear cells disposed along the dermoepidermal junction and migrating into the epidermis were CD8-positive lymphocytes, whereas the dermal inflammatory infiltrates were composed predominantly of CD4-positive lymphocytes. This case showed the potential usefulness of patch testing in evaluating cases of toxic epidermal necrolysis. We believe that delayed hypersensitivity plays a crucial role in the development of drug-induced toxic epidermal necrolysis. Furthermore, potential effector cells with phenotypic characteristics of CD8-positive lymphocytes (suppressor/cytotoxic T cells) seem to represent important mediators of the epidermal damage of the cutaneous lesion in our case.

Early pathological features of the cornea in toxic epidermal necrolysis

“…These subtle changes are similar to epidermal findings in cutaneous TEN4 and may have contributed to epithelial damage. Direct attack through cytotoxic T cells could be mediated by TNFα 2 14.…”

Pulmonary complications in toxic epidermal necrolysis: a prospective clinical study

“…Cell-mediated cytotoxicity has been suggested by infiltration of inflammatory cells in areas of epidermal necrolysis [20,21]. Among these ceils, monocytes/macrophages and T-cell lymphocytes infiltrating dermis and epidermis could play a crucial role via local TNFa and cytotoxic secretion [22][23][24]. It is noteworthy that the predominant inflammatory cells infiltrating bronchial mucosa in patients developing "specific" TEN bronchial mucosal involvement mainly consisted of mononuclear cells.…”

Evaluation of the Potential Role of Cytokines in Toxic Epidermal Necrolysis

“…These findings strongly suggest that these cells are not bystander lymphocytes but probably play a role in the destruction of epidermal cells. Anyhow, in skin biopsies of early lesions of TEN, there are rather low numbers of CD8 T lymphocytes within the epidermis (Miyauchi et al, 1991), suggesting that the intervention of soluble mediators may be necessary for amplifying the apoptosis of keratinocytes. Several pathways could be implicated in the apoptosis of keratinocytes in TEN.…”