What serious complication can occur following a stem cell or bone marrow transplant?

Graft-versus-host disease (GVHD) is a significant and serious complication that can arise after a stem cell or bone marrow transplant. This condition occurs when the transplanted immune cells from the donor (the graft) recognize the recipient's body (the host) as foreign and mount an immune response against it. This can lead to severe reactions affecting the skin, liver, and gastrointestinal tract, among other organs.

While other complications such as organ rejection, infections, and bleeding disorders can occur in the context of transplants, GVHD specifically pertains to the unique immunological interactions that occur after the infusion of donor cells, particularly in allogeneic transplants where the donor and recipient are not genetically identical. These other complications are important to consider in the overall context of post-transplant care, but GVHD remains a distinguishing concern primarily linked to the immune responses in transplant scenarios.