Colonic graft-versus-host disease

摘要

Although colonic GVHD is readily diagnosed, advances in management await greater understanding of pathogenesis and more specifically targeted therapies.Graft-versus-host disease (GVHD) is a major complication of hematopoietic stem cell transplantation (HSGT). For a GVHD reaction to occur, three conditions must be met. Initially, there is introduction of immunologically competent T cells with the graft. Second, the host must have antigenic differences with the graft that are capable of stimulating donor T cells. Finally, the host immune system must be incapable of generating a response sufficient to reject the graft [1,2*"]. Differences in major and minor antigens of the human leukocyte antigen (HLA) system are the primary determinants of the likelihood of GVHD. Clinically significant acute GVHD is seen in 20 to 50% of patients after HLA-matched sibling HSGT. If the donor is unrelated or an HLA-mismatched sibling, the incidence of significant acute GVHD increases to 60 to 80% [3].The necessary conditions for GVHD can occur after solid organ transplantation as well. Although GVHD has been reported after most types of solid organ transplantations, it is a rare complication in that setting [4""].