Hemorrhage is an infrequent complication of renal disease. Thrombocytopenia may occur, but is usually mild. Mucosal bleeding, reduced platelet retention and a prolonged BMBT are features of natural and experimental uremia in dogs. These abnormalities correlate to the degree of azotemia. Platelet aggregation is either normal or mildly decreased, implicating defective platelet adhesion as the main hemostatic abnormality. The exact cause of the defect is unknown. The amount and multimeric composition of vWf in uremic dogs is normal, indicating that the adhesion defects are not due to vWf abnormalities.
Hypercoagulability (thrombosis) is a feature of nephrotic syndrome in both man and dogs. This is mainly due to loss of antithrombin through the glomerulus, with antithrombin activities < 50% predisposing to thrombosis in dogs. Platelet hyperaggregability (from increased free arachadonic acid availability, due to decreased albumin binding from hypoalbuminemia), hyperfibrinogenemia and decreased fibrinolysis (due to urinary losses of plasminogen or increased levels of inhibitors, such as alpha2-antiplasmin) may contribute.
|
