Graft vs Host Reaction (GVHR) is a medical condition that occurs most commonly following a bone marrow or stem cell transplant, wherein the transplanted cells (graft) recognize the recipient's tissues (host) as foreign and mount an immune response against them. This immune reaction can be classified into two categories: acute GVHR and chronic GVHR.
Acute GVHR typically occurs within the first few months after transplantation and is characterized by damage to the skin, liver, and intestines, among other organs. Symptoms may include rash, nausea, diarrhea, and liver dysfunction. Acute GVHR can range in severity from mild to life-threatening, with severe cases requiring immediate medical intervention.
Chronic GVHR, on the other hand, develops gradually and can occur months to years after transplantation. It is characterized by ongoing inflammation in multiple organs, including the skin, mouth, eyes, liver, and lungs. Symptoms may include dry and itchy skin, mouth ulcers, impaired vision, and lung complications. Chronic GVHR can significantly impact patients' quality of life and may require long-term immunosuppressive therapy to manage adequately.
Both acute and chronic GVHR result from mismatches in the human leukocyte antigen (HLA) between the donor and recipient, causing the transplanted immune cells to perceive the recipient's tissues as foreign. Strategies to prevent or treat GVHR may involve careful matching between donor and recipient HLA, immunosuppressive medications, and other supportive measures to mitigate the detrimental effects of the immune response.
