Case with Brunsting–Perry‐like localized subepidermal blister formations and immunoglobulin G antibodies against unidentified basement membrane zone antigen

Brunsting–Perry type bullous pemphigoid is defined by the blister formation limited to the head and neck, and autoantibodies to type VII collagen are detected in several cases. However, the pathomechanisms and autoantigens in this condition remain unknown. We report a 20‐year‐old female patient with a more than 2‐year history of recurrent tense blisters localized on the face with no distinct atrophic scar formation. The patient had neither extensive sun exposure nor a history suggestive of contact dermatitis. Oral betamethasone was effective on the skin lesions. Histopathology revealed subepidermal blister formation with dermal infiltrates of neutrophils. Although direct and indirect immunofluorescence tests detected immunoglobulin G antibodies to the basement membrane zone (BMZ), no known dermal or epidermal autoantigens were detected in immunoblot analyses. Therefore, this case may be a rare variant of Brunsting–Perry type localized bullous pemphigoid with autoantibodies to an undetermined BMZ antigen.