graftversushostDisease

Graft-versus-host disease (GVHD) is a condition that can occur after allogeneic hematopoietic stem cell transplantation when donor immune cells recognize the recipient’s tissues as foreign and mount an immune response. GVHD is categorized as acute or chronic, based on timing and clinical features, with acute GVHD typically occurring within the first 100 days and chronic GVHD developing later. The condition most often affects the skin, liver, and gastrointestinal tract, but it can involve other organs such as the lungs, eyes, and mouth.

Pathophysiology involves donor T cells that react against host antigens, aided by immune signals and inflammatory cytokines. Risk factors include HLA mismatches between donor and recipient, minor histocompatibility antigen differences, the source of stem cells (peripheral blood mobilization can have higher GVHD risk), recipient age, prior GVHD, and the intensity of the conditioning regimen used before transplantation.

Clinical features of acute GVHD include a maculopapular rash, bilirubin elevation indicating liver involvement, and gastrointestinal symptoms such as diarrhea or abdominal pain. Chronic GVHD presents with more prolonged, varied symptoms that can resemble autoimmune diseases, including skin thickening or dry eyes and mouth, joint stiffness, liver involvement, and GI symptoms.

Diagnosis is primarily clinical, supported by the pattern of organ involvement; tissue biopsy can aid confirmation in suspected cases. Management focuses on prevention with immunosuppressive prophylaxis (for example, calcineurin inhibitors and methotrexate) and treatment of established GVHD with systemic corticosteroids as first-line therapy. For steroid-refractory or dependent disease, therapies such as ruxolitinib and other immunomodulatory approaches, including extracorporeal photopheresis, may be used. Prognosis varies with severity, organ involvement, and response to therapy, with chronic GVHD contributing to long-term morbidity.