Molecular markers of hemostasis activation in nephrotic syndrome.

Fibrinopeptide A (FPA), a sensitive index of in vivo thrombin activity, beta-thromboglobulin (beta TG) and platelet factor 4 (PF4), specific markers of platelet intravascular activation, have been measured in plasma by radioimmunoassays in 23 patients with nephrotic syndrome and in 32 normal subjects. FPA concentration was 2.40 +/- 1.42 ng/ml (mean +/- SD) in nephrotic patients and 1.16 +/- 0.58 ng/ml in normal controls (p less than 0.001); beta TG concentration was 57.9 +/- 33.2 ng/ml in nephrotic patients and 25.7 +/- 7.4 ng/ml in controls (p less than 0.001); PF4 level was not different from controls. These data indicate in vivo blood hypercoagulability and platelet hyperfunction in nephrotic syndrome. Moreover, we have documented a slow in vitro FPA generation pattern (delta FPA): 0.97 +/- 0.51 ng/ml/10 min; this suggests that thrombin activity is predominantly local.