Impaired fibrinolysis and protein C increase after cadaver kidney transplantation

Abstract

Severe rejection crises occurred in 13 out of 20 cadaver kidney recipients; removal of the graft was inevitable in 10 cases. The plasminogen levels were found to be lower (76.5±2.9%) in the 13 patients with impaired graft acceptance (group B) than in the 7 patients experiencing only moderate rejection (group A, 93.7±5.2%, p<0.01) or the 41 patients with chronic renal disease (group C, 88.2±2.3%, p<0.01). Since α 2-antiplasmin was found to be enhanced, the α 2-antiplasmin/ plasminogen ratio was high (1.56±0.07) in group B as compared with group A (1.19±0.05, p<0.002) and group C (1.11±0.04, p<0.001). The fibrinolytic capacity, which was assessed by a “reversed fibrin plate” assay, declined significantly after transplantation, and was lower in group B >20 days after grafting. The neoantigen α 2-antiplasmin-plasmin complex was not detected in any patient; thus hyperfibrinolysis is unlikely to be responsible for the plasminogen decrease. Protein C rose above preoperative values (group A 117.1±8.7%; group B 133.7±9.0%) and reached higher levels in group A (221±24.1%) than in group B (157.4±14.8%, p<0.05) between days 11 and 20 after transplantation. No constant alterations were found with respect to antithrombin III and fibrinogen. Fibrin deposits, which reduce perfusion, can be found in the vessels of rejected kidney grafts. An impaired fibrinolytic capacity and a subsequent inability to remove these clots may be significant for the outcome of transplantation.