Coexistence of pemphigus and bullous pemphigoid

Widespread tense blisters developed on a 60-year-old Japanese man who had been diagnosed with pemphigus 11 years earlier, because of a history of pruritic erythema and erosions on his face, chest, and back, mild supra-basal layer blister formation found in a biopsy specimen, and a positive direct immunofluorescence test showing IgG deposition in the intercellular space. The histological findings showed subepidermal blister, and the immunoblot study detected 180kD bullous pemphigoid antigen. Direct immunofluorescence test revealed intercellular staining for IgG, and indirect immunofluorescence tests repeatedly demonstrated the presence of circulating antibodies to the intercellular space. From these observations, this case suggests the coexistence of pemphigus and bullous pemphigoid.