GVHD

Graft-versus-host disease (GVHD) is a complication that can occur after an allogeneic transplant, most commonly hematopoietic stem cell transplantation. It arises when donor immune cells recognize the recipient’s tissues as foreign and mount an immune attack. GVHD can also occur, though less commonly, after solid organ transplantation or transfusion with donor cells. It is broadly categorized into acute and chronic forms, based on timing and clinical features.

Acute GVHD typically develops within the first 100 days after transplantation, though it can occur later. It most often involves the skin, liver, and gastrointestinal tract. Skin symptoms range from a rash to generalized shedding; liver involvement can cause jaundice and elevated liver tests; gastrointestinal disease can cause diarrhea, vomiting, and abdominal pain. The severity of acute GVHD is graded from I to IV, guiding treatment decisions.

Chronic GVHD usually emerges later and can resemble autoimmune or fibrotic diseases. It frequently affects the skin (sclerotic changes, restricted movement), eyes, mouth, lungs, liver, and other organs. Chronic GVHD is a major source of long‑term morbidity and nonrelapse mortality after transplantation and may require prolonged immunosuppressive therapy.

Pathophysiology involves donor T cells recognizing host antigens as foreign, leading to cytotoxic and inflammatory responses. Risk factors include HLA mismatch, older age, female-to-male donors, intensity of conditioning regimens, and inadequate GVHD prophylaxis.

Treatment centers on prevention with matching and prophylactic immunosuppression, and on immunosuppressive therapy for established disease. First-line therapy for acute GVHD is typically systemic corticosteroids; additional agents include calcineurin inhibitors and, for steroid-refractory cases, therapies such as ruxolitinib. Chronic GVHD management may involve corticosteroids plus other immunosuppressants or targeted therapies, with attention to infection risk and quality of life.