Excess soluble urokinase-type plasminogen activator receptor in the plasma of dialysis patients correlates with increased fibrinolytic activity

IntroductionElevated levels of soluble urokinase-type plasminogen activator receptor (suPAR) and other fibrinolytic parameters related to the urokinase-type plasminogen activator (uPA) system can be implicated in clot lysis in plasma. In this study, we examined whether the excess suPAR was associated with increased plasma fibrinolytic activity, determined as plasmin/antiplasmin (PAP) complexes in dialysis patients.Materials and methodsTwenty-six patients on maintenance haemodialysis (HD) and 18 on maintenance peritoneal dialysis (CAPD) were examined together with 20 healthy controls. Pre-dialysis blood levels of suPAR, uPA and PAP were determined using commercially ELISA kits.ResultssuPAR, uPA, PAP levels and suPAR/uPA ratio were increased in both groups of dialyzed patients compared to the controls. Moreover, increased suPAR levels directly correlated with those of uPA and PAP (r = 0.443 and r = 0.393, both p < 0.01, respectively); the fibrinolytic markers were also positively associated with each other (r = 0.506, p < 0.001).ConclusionsThe plasma suPAR antigen levels are significantly increased in uraemic patients undergoing maintenance dialysis compared with healthy volunteers and are closely associated both with uPA as well as PAP. These positive associations suggest a link between suPAR and the fibrinolytic activity in these patients.