Toxic epidermal necrolysis and graft vs. host disease: a clinical spectrum but a diagnostic dilemma.

We describe a 53-year-old man who developed partial and full thickness skin loss associated with pyrexia, diarrhoea, liver, renal and bone marrow failure, during treatment for an aggressive B cell lymphoblastic lymphoma. The clinical features and histology were compatible with both toxic epidermal necrolysis and graft vs. host disease, causing a diagnostic and therapeutic dilemma. We discuss the possibility that methotrexate was the causative drug, with review of its cutaneous side-effects. Histologically our patient demonstrated the sparse dermal infiltrate with full thickness epidermal necrosis typical of toxic epidermal necrolysis and graft vs. host disease. We discuss this finding with respect to the pathogenesis of toxic epidermal necrolysis.