Research Communications of the 24th ECVIM-CA Congress

Urs Giger and Raj Karthik are also part of the laboratory that offers DNA testing for this mutation. Fibrinogen decreases when coagulation is activated to form fibrin, while FDPs and D-dimers represent the products of fibrinolysis. In humans, activation of coagulation and fibrinolysis develops in all type of ascites and it is also associated with signs of systemic fibrinolysis.These results have lead to the suggestion that ascitic fluid is inherently fibrinolytic. Preliminary studies showed similar results also in dogs (JAVMA Nov. 2012 , ECVIM proceedings 2013 . In addition, in an old experimental study conducted in dogs, inoculation of blood or of a solution containing fibrinogen and thrombin into the pleural cavity resulted in the activation of the coagulation system followed by fibrinolysis. Therefore, the objective of the present study was to determine whether the activation of coagulation and fibrinolysis (i.e. low fibrinogen and elevated FDPs and Ddimer) occurs not only in the ascitic fluid, as alredy been demonstrated, but also in all type of pleural effusions in dogs. Thirty-three dogs referred to the San Marco Veterinary Clinic with pleural effusion, but without ascites, were studied. Fibrinogen, FDPs, and D-dimer concentrations were measured and then compared in both pleural fluid and venous blood via Wilcoxon signed ranks test. The dog's pleural effusions were categorized based on pathophysiology of fluid formation into 5 dogs with transudate (4 due to increased hydrostatic pressure and 1 due to decreased osmotic pressure), 23 with an exudate (of which 11 due to septic causes), 4 with a haemorrhagic pleural effusion, and 4 with a chylous effusions. The fibrinogen concentration in the pleural effusion (median: 59 mg/dL; range: 59-59) was significantly lower (p < 0.0001) than the plasma fibrinogen concentration (median: 419 mg/dL; range: 131-1406). In all dogs, the fibrinogen pleural fluid concentration was lower than the plasma concentration. The FDP concentration in the pleural effusion (median: 151 mg/dL; range: 0.69-151) was significantly (p < 0.0001) higher than plasma FDPs concentrations (median: 5.55 mg/dL; range: 0.83-108.47). In 1 case, the FDPs pleural fluid concentration was lower than the plasma concentration and in 32 cases the pleural fluid concentration was higher. The D-dimer concentrations were significantly(p < 0.0001) higher in the pleural effusion (median: 3.84 lg/mL; range: 0.05-9.61) than in the plasma (median: 0.07 lg/mL; range: 0.01-7.67). In one case, the D-dimer pleural fluid concentration was lower than the plasma concentration and in 32 cases was higher. These findings support the hypothesis that activation of coagulation followed by fibrinolysis occurs in all type of pleural effusions.