Bullous systemic lupus erythematosus: revised criteria for diagnosis.

Blistering in systemic lupus erythematosus has been divided into three groups. A specific subgroup of 'bullous systemic lupus erythematosus' has been defined by Gammon et al. on the basis of a number of criteria. From our experience of seven patients with bullous systemic lupus erythematosus, and after reviewing the literature, we suggest that the current classification is too narrow. Our patients displayed clinical and immunohistological (based on direct and indirect immunofluorescence and Western immunoblotting) heterogeneity. Sera from two patients bound to epidermal epitopes in sodium chloride-split skin, but immunoblotting was negative. In neither of these patients could the target antigen be type VII collagen, the only antigen identified as pathogenic in this disease. Patients with epidermal binding should not be excluded from a diagnosis of bullous systemic lupus erythematosus. SLE is a disease in which there is a genetic predisposition to form antibodies to type VII collagen, along with other autoantibodies, many of which may be implicated in blistering. We suggest that the criteria for the diagnosis of BSLE should be revised. We define this disease as an acquired subepidermal blistering disease in a patient with SLE, in which immune reactants are present at the basement membrane zone on either direct or indirect immunofluorescence.