A Case of Pemphigoid with Autoantibodies to Laminin 332 α3 Subunit without Mucosal Involvements Associated with Psoriasis Vulgaris

Abstract

A 38-year-old man with a 10-year history of psoriasis vulgaris presented pruritic urticarial plaques and blisters on his entire body, but without any mucosal involvements. Direct immunofluorescence revealed linear deposits of immunoglobulin (Ig) G and C3 along the basement membrane zone (BMZ). Indirect immunofluorescence (IIF) demonstrated circulating IgG antibodies to BMZ of normal human skin. IIF using 1M NaCl-split skin revealed IgG antibodies reacting with the dermal side of the split skin revealing. IgG immunoblotting of recombinant laminin 332 reacted positively with the 165 kDa α3 subunit. We diagnosed this case as pemphigoid with autoantibodies to laminin 332 α3 subunit accompanied by psoriasis vulgaris and started oral administration of cyclosporine A. This is a rare case of anti-laminin 332 pemphigoid associated with psoriasis.