Detection of anti-basement membrane zone antibodies in bullous systemic lupus erythematosus.

We describe a 42-year-old black woman with long-standing systemic lupus erythematosus in whom vesiculobullous lesions developed. Routine histologic and immunologic studies fulfilled the criteria for the diagnosis of bullous systemic lupus erythematosus. Indirect immunofluorescence showed antinuclear antibodies without basement membrane zone fluorescence. We destroyed the nuclear antigens of the indirect immunofluorescence substrate with 2 mol/L sodium chloride, which unmasked basement membrane zone linear IgG staining. We also confirmed anti-basement membrane zone antibodies by employing a new technique of direct immunofluorescence on sodium chloride-split skin. Our finding prove that a thorough search for anti-basement membrane zone antibodies can be revealing. Our results support the idea that a subset of bullous systemic lupus erythematosus has the staining characteristics of epidermolysis acquisita, with the dermal side of the split skin showing linear immunoglobulin deposition.