Anti-laminin 332 antibodies in graft-versus-host disease-associated bullous pemphigoid after allogeneic peripheral blood stem cell transplantation.

We report a 48-year-old woman with bullous pemphigoid (BP) with antibodies against the B3 subunit of laminin 332 after the development of graft-versus-host disease (GVHD). She was diagnosed with recurrent acute lymphoblastic leukemia at 40 years of age and underwent two rounds of allogeneic peripheral blood stem cell transplantations (PBST). Two and a half years after the second PBST, multiple tense blisters appeared on her face, hands, and lower legs. The diagnosis of BP was based on hematoxylin eosin and immunofluorescence staining and immunoblotting analyses. A combination regimen of topical corticosteroids (clobetasol propionate) and tetracycline/niacinamide was administered. Complete clinical resolution was achieved after four weeks of therapy without the use of immunosuppressive drugs. To maintain the graft-versus-tumor effect, topical corticosteroids and immunomodulatory drugs are preferred for BP after hematopoietic stem cell transplantation considering the risk of recurrence of hematologic malignancies. To date, there have been no reports of successful treatment of GVHD-associated BP without immunosuppressive drugs. Chronic GVHD is characterized by the production of autoantibodies. Furthermore, this autoimmune subepidermal blistering disease, BP, may be a manifestation of chronic GVHD. However, the precise mechanism of autoantibody production in chronic GVHD is not yet fully elucidated.