Alteration of some natural anticoagulants in dogs with chronic renal failure

The diagnosis of hypercoagulation is essential for the identification of individuals at high risk for thrombosis and for early treatment of thrombotic disorder. The objective of the study was to evaluate some parameters for assessing the prothrombotic state in dogs with chronic renal failure (CRF). Some natural anticoagulants, protein C (PC), protein S (PS), and antithrombin III (AT III), as well as fibrinogen concentration and clinical chemistries, were concentrated. The study groups consisted of 42 dogs with CRF and 34 age- and sex-matched clinically healthy control dogs. The level of AT III in the CRF group was significantly lower (P < 0.05), but the fibrinogen concentration was significantly higher (P < 0.05) than in the control group. Additionally, the cholesterol level in the CRF group was significantly higher than in the control group (P < 0.05) and was positively correlated to creatinine (R = 0.5, P < 0.05). Elevated levels of PC and PS were exhibited in eight dogs with subcutaneous edema. The increased levels of PC and PS may counterbalance the reduction of AT III and may be related to the magnitude of hypoalbuminemia and proteinuria. These seem to be preventive mechanisms against thromboembolic phenomena. Simple correlations among parameters were determined for the CRF group. The fibrinogen concentration was correlated inversely with the AT III level (R = −0.63, P < 0.05). A negative correlation between AT III and azotemic parameters (creatinine: R = −0.68, P < 0.05; blood urea nitrogen (BUN): R = −0.65, P < 0.05) was observed also. In contrast, the fibrinogen concentration was positively correlated to creatinine (R = 0.66, P < 0.05) and BUN (R = 0.67, P < 0.05). The study concluded that there was a significant reduction in AT III and hyperfibrinogenemia, which were predictable parameters for thrombotic tendency in the dogs with CRF. Hypercholesterolemia was the other risk factor.