Polymyositis as a manifestation of chronic graft-versus-host disease after allo-HSCT.

Patients who received allogeneic haematopoietic stem cell transplantation (allo-HSCT) may develop T cell-mediated immunologic injury to muscles, recapitulating the characteristics of polymyositis clinically and pahtologically. Polymyositis is a rarely reported complication of graft-versus-host disease (GVHD), which often responds well to corticosteroids and immunosuppressive treatment.