Graft-versus-host disease

Principles to understand

• when immunocompetent bone marrow cells are transplanted, they may recognize the host as foreign even when the HLA is identical. this is because there may be single nucleotide polymorphism (snp) differences

• this does not happen with identical twins, but identical twins have a high chance of having the same disease so might be unsuitable donors for such a reason; it happens sometimes with siblings; it happens more frequently with living unrelated donors

• stem cell transplants in animals seem to avoid this because of thymocyte education and lack of mature T cells in the transplant

GVH rashes

• rashes all look about the same

• the history tells you a lot

• the patient probably has diarrhea, inflamed lungs

Category: Pathology Notes