What is graft-versus-host disease (GVHD)?
GVHD is a process in which donor T-cells “attack” the host cells, manifesting primarily in skin, liver and gastrointestinal complications. It is a frequent complication of allogeneic hematopoetic cell transplant (HCT), stem cell or bone marrow, though it has been reported rarely in syngeneic (from a twin donor) and autologous HCT. In addition, GVHD can be a rare complication of blood transfusion (irradiation of product prevents GVHD) or solid organ transplant. GVHD is a significant cause of morbidity and mortality in allogeneic HCT; with a 30-50% incidence in HLA matched sibling donor transplants and 65-70% incidence with unrelated donors. GVHD has traditionally been defined as: • Acute: occurring within the first 100 days after transplant • Chronic: occurring after 100 days and can last months to years after Recently, it is recognized that the timing of onset is insufficient to distinguish acute from chronic GVHD, and more attention is paid to clinical manifestations rather than tempo
