Management of acute graft versus host disease (GvHD).

Graft versus host disease (GvHD) is a frequent complication of allogeneic hemopoietic stem cell transplantation (HSCT), and of donor lymphocyte infusions (DLI): the acute form occurs within 100 days from HSCT or DLI, the chronic form beyond day +100. GvHD should be prevented rather than treated. There are several ways to prevent GvHD: remove donor T cells from the transplant (ex vivo T-cell depletion), administer T-cell antibodies to the patient (in vivo T-cell depletion), administer immunosuppressive drugs such as methotrexate, cyclosporin, tacrolimus, and mycofenolate (post-transplant immunosuppression). New strategies of GvHD prophylaxis include the infusion of expanded mesenchymal stem cells and downregulation of host antigen-presenting cells. First-line treatment of established GvHD is based on low-dose corticosteroids (0.5-2 mg/kg). Second-line therapy for steroid refractory GvHD is unsatisfactory. The early administration of T-cell antibodies and/or TNF antibodies and TNF soluble receptor may be successful in some cases, but they do not seem to fulfill the expectations. High-dose chemotherapy has not been explored thoroughly. Acute GvHD is complicated by infections that cause significant morbidity and mortality: prophylaxis, early diagnosis and treatment of infections are an integral part of GvHD management. We have considerably reduced the risk of acute GvHD over the past three decades: we need to further improve these results, with the final goal of dissecting, if possible, the graft versus host from the graft versus tumor effect.