Graft-Versus-Host Disease

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Graft-Versus-Host Disease




• Multiorgan disorder that most commonly results from the transfer of donor hematopoietic stem cells into a recipient via an allogeneic hematopoietic stem cell transplant (HSCT).


• Despite advances in HSCT procedures and post-transplantation immunosuppressive therapy, more than half of HSCT recipients develop chronic graft-versus-host disease (GVHD), which remains a major cause of morbidity and mortality.


• Table 44.1 lists risk factors for GVHD in HSCT recipients.



• Less frequent settings of GVHD include transfusion of non-irradiated blood products to an immunocompromised patient, maternal–fetal transmission to an immunodeficient neonate, and solid organ transplantation.


• Divided into acute and chronic forms based on clinical features.


• Pathogenesis of acute GVHD occurs in three steps: (1) HSCT conditioning regimen leads to epithelial cell injury and activation of host antigen presenting cells; (2) activation of donor T cells; (3) tissue destruction by cytotoxic T cells, natural killer cells, and soluble factors (e.g. tumor necrosis factor-α [TNF-α]).


• Chronic GVHD shares features (e.g. autoantibody production, cutaneous sclerosis) with autoimmune connective tissue diseases.


• Histologically, acute GVHD and epidermal involvement in chronic GVHD are characterized by variable degrees of keratinocyte necrosis (often accentuated in appendages), vacuolar degeneration of the basal layer, and a band-like lymphocytic infiltrate.



Acute GVHD



• Most often arises 4–6 weeks after HSCT with traditional regimens.


• Persistent, recurrent, and late-onset variants of acute GVHD can occur during a time period (>100 days post-transplant) traditionally reserved for chronic GVHD, especially following interventions such as tapering of immunosuppression and donor lymphocyte infusions.


• Typically presents as a morbilliform exanthem, often with perifollicular accentuation.


• Initial predilection for acral sites (e.g. dorsal hands and feet, palms, soles, ears), forearms, and upper trunk.


• Clinical staging is based on the proportion of the cutaneous surface involved: Stage 1, <25%; Stage 2, 25–50%; and Stage 3, >50%. Stage 4 represents erythroderma with bullae/epidermal detachment resembling toxic epidermal necrolysis (Fig. 44.1).


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Apr 22, 2016 | Posted by in Dermatology | Comments Off on Graft-Versus-Host Disease

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