Diagnostic performance of direct immunofluorescence microscopy studies by biopsy sites in autoimmune subepidermal blistering dermatoses: a prospective study.

The diagnosis of autoimmune subepidermal blistering diseases, such as bullous pemphigoid (BP), critically relies on the detection of tissue-bound immunoreactants along the epidermal basement membrane by direct immunofluorescence microscopy (DIF) studies of skin biopsy specimens obtained from perilesional skin 1,2 . However, there was surprisingly no consensus among international experts about the definition of perilesional skin 1 . The latter was considered as either normal appearing skin surrounding an inflamed area or erythematous skin adjacent to a blister.