Hypercoagulation and hypofibrinolysis in horses with colic and DIC.

Changes in haemostasis in horses with colic were assessed by using specific and sensitive markers of coagulation and fibrinolysis activity. Blood samples from 41 horses with severe colic and from 30 healthy control horses were tested. Diagnosis of DIC was based on the findings of at least 3 of 6 abnormalities: thrombocytopenia, prolonged clotting times (PT and APTT), increased polyclonal FDPs, decreased fibrinogen and decreased AT-III activity. Plasma thrombin-antithrombin III complexes (TAT), monoclonal fibrin degradation products fragment D (D-dimer) and monoclonal fibrinogen degradation products (FgDP) were also tested by using ELISA kits. DIC was diagnosed in 16 of 41 horses with colic. Compared to control and non-DIC colic values, TAT was significantly (P < 0.000) greater in horses with colic and DIC (Control group, mean +/- s.d. 2.6 +/- 2; non-DIC colic group, 7.5 +/- 9, and DIC colic group, 30.9 +/- 36 ng/ml). Also, D-dimer was significantly (P < 0.000) less in the DIC group when compared to control and non-DIC colic values (mean +/- s.d. 677 +/- 119, 682 +/- 220 and 399 +/- 234 ng/ml, respectively). Compared to non-DIC colic values, FgDP was significantly (P < 0.05) lower in the DIC group (363 +/- 111, 437 +/- 230 and 293 +/- 187 ng/ml respectively). Both PT and APTT showed a significant positive correlation with TAT. DIC was more common among nonsurvivors and horses with ischaemic bowel. We conclude that a hypercoagulative state was detected in horses with colic, which was stronger in horses with colic and DIC. Hypofibrinolysis was present only in horses with DIC. Therefore, marked hypercoagulation together with hypofibrinolysis are associated with DIC in horses.