Fibrin clot structure in patients with end-stage renal disease.

Fibrin clots with reduced permeability, increased clot stiffness and reduced fibrinolysis susceptibility may predispose to cardiovascular disease (CVD). Little is known, however, about the structure of fibrin clots in patients with end-stage renal disease (ESRD). These patients suffer from a high risk of CVD in addition to their chronic low-grade inflammation. Using permeability, compaction and turbidity studies in 22 ESRD patients and 24 healthy controls, fibrin clots made from patient plasma were found to be less permeable (p < 0.001), less compactable (p < 0.001), and less susceptible to fibrinolysis (p < 0.001) than clots from controls. The maximum rate of turbidity increase was also higher for the patients than controls (p < 0.001), and scanning electron microscopy revealed higher clot density of fibrin fibers in clots from patients than clots from controls (p < 0.001). Patients had higher plasma concentrations of fibrinogen, C-reactive protein and interleukin 6 than controls. These plasma markers of inflammation correlated significantly with most of the fibrin structure characteristics observed in the patients. In contrast, plasma markers of azothemia showed no such correlations. The results suggest that in ESRD patients fibrin clots are significantly different from healthy controls, and that the fibrin structure characteristics in the patients are associated primarily with the inflammatory plasma milieu rather than with level of azothemia.