Disseminated intravascular coagulation in cats

The purpose of this study was to describe the clinical characteristics of cats with disseminated intravascular coagulation (DIC), including associated diseases and hemostatic abnormalities, and to identify risk factors for death and treatments that potentially altered outcome. Medical records for cats with DIC from 1990-2004 were evaluated retrospectively. Inclusion criteria were the presence of an underlying disorder associated with DIC and either postmortem examination findings of intravascular fibrin deposition or thrombosis, or both of 2 or more organs or coagulation profiles that meet 3 of 5 criteria: prolonged prothrombin time (PT), activated partial thromboplastin time (aPTT), presence of fibrin degradation products (FDP), low plasma fibrinogen (FIB) concentration, and thrombocytopenia (<160,000 platelets/microL). Signalment, historical data, clinical findings, clinicopathologic data, underlying disorders, management, and outcome were recorded. Forty-six cats fulfilled the criteria for DIC. Cats ranged in age from 7 weeks to 17 years (median, 9 years). Hemorrhage was noted in 7 of 46 cats (15%). Three of 46 cats (7%) survived, whereas 43 of 46 (93%) died or were euthanized. The most common underlying disorders were lymphoma, other forms of neoplasia, pancreatitis, and sepsis. There was no association detected between outcome and signalment; underlying disease; hemorrhage; abnormalities in aPTT, FIB, FDPs, platelet count; transfusion of blood products; and heparin therapy. However, the median PT of nonsurvivors was more prolonged than in survivors (P < .005). DIC in cats can result from a variety of neoplastic, infectious, and inflammatory disorders, and is associated with a high case fatality rate.     

Proteins invoked by vitamin K absence and clotting times in clinically ill cats

The clinical utility of the Thrombotest, a method for determining the prothrombin time that is uniquely sensitive to the presence of proteins invoked by vitamin K absence (PIVKA), was prospectively evaluated and compared to routine coagulation tests in cats with clinically suspected bleeding tendencies. Abnormal PIVKA clotting values were determined by comparison to results of a concurrently evaluated pooled feline plasma sample and by use of an absolute cutoff value of 25.2 seconds. To be recognized as abnormal, PIVKA clotting values had to be >20% of the pooled feline plasma PIVKA clotting time (the "20% rule") or > or =25.2 seconds (mean + 2 standard deviations of 150 different pooled feline plasma samples). Among the disorders in the population examined were 74 cats with liver disease and 19 cats with severe inflammatory bowel disease. Overall, a prolonged PIVKA clotting time based on the 25.2-second cutoff was found in 39.3% of cats, and based on the 20% rule in 40.7% of cats. An abnormal prothrombin time (PT) developed in 5.8% of cats, an abnormal APTT in 14% of cats, subnormal fibrinogen in 8.8% of cats, and thrombocytopenia in 3.3% of cats. Bleeding tendencies were confirmed in 22 cats, of which abnormal PIVKA clotting times were recognized in 95.5%, abnormal PT in 21%, abnormal activated partial thromboplastin time in 25%, hypofibrinogenemia in 16.7%, and thrombocytopenia in 4.5%. Response to treatment with vitamin K was demonstrated in 21 of 24 cats with an abnormal PIVKA clotting time. In these cats, an abnormal PIVKA clotting time normalized within 3 to 5 days of parenteral vitamin K administration. Cats responding to vitamin K administration had hepatic lipidosis (n = 7), severe inflammatory bowel disease (n = 4), severe inflammatory bowel disease associated with cholangiohepatitis (n = 5), and miscellaneous disorders (n = 5). Using either endpoint, the PIVKA clotting time is more sensitive for the detection of cats with coagulopathies than routinely used coagulation assessments in our hospital. Our findings confirm that cats with hepatic lipidosis, severe cholangiohepatitis, and severe inflammatory bowel disease develop coagulopathies responsive to vitamin K administration.