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Related to chronic rejection: Acute Rejection
a transplant rejection occurring gradually, sometimes months later.
rejectionImmunology An immune reaction evoked by allografted organs; the prototypic rejection occurs in renal transplantation, which is subdivided into three clinicopathologic stages. See Cyclosporin A, Graft rejection, Graft-versus-host disease, Second set rejection, Tacrolimus, Transplant rejection.
Hyperacute rejection Onset within minutes of anastomosis of blood supply, which is caused by circulating immune complexes; the kidneys are soft, cyanotic with stasis of blood in the glomerular capillaries, segmental thrombosis, necrosis, fibrin thrombi in glomerular tufts, interstitial hemorrhage, leukocytosis and sludging of PMNs and platelets, erythrocyte stasis, mesangial cell swelling, deposition of IgG, IgM, C3 in arterial walls
Acute rejection Onset 2-60 days after transplantation, with interstitial vascular endothelial cell swelling, interstitial accumulation of lymphocytes, plasma cells, immunoblasts, macrophages, neutrophils; tubular separation with edema/necrosis of tubular epithelium; swelling and vacuolization of the endothelial cells, vascular edema, bleeding and inflammation, renal tubular necrosis, sclerosed glomeruli, tubular 'thyroidization' Clinical ↓ Creatinine clearance, malaise, fever, HTN, oliguria
Chronic rejection Onset is late–often more than 60 days after transplantation, and frequently accompanied by acute changes superimposed, increased mesangial cells with myointimal proliferation and crescent formation; mesangioproliferative glomerulonephritis, and interstitial fibrosis; there is in general a poor response to corticosteroids
chron·ic re·jec·tion(kronik rē-jekshŭn)
Rejection of surgical transplant occurring gradually, sometimes months later.