Coagulation

FDP Case Study: (January 1999)

Recently, we received laboratory work on a four-year old German Shepherd dog, which was hit by a car. The CBC results showed RBC fragments and a severe thrombocytopenia, suggestive of DIC.

FDP, APTT, and PT were ordered. The FDP tube never clotted, and a second one was obtained with similar results. The FDP test was positive in all dilutions, and the result was >80ug/ml.

The FDP tube never clotted because of the severe DIC the animal was experiencing. All of the fibrinogen was depleted in forming microthrombin characteristic of DIC. If there is no fibrinogen, no fibrin can be formed. The PT and APTT results were >200 seconds. Again the reason for this is because all of the coagulation factors were used up as a result of the DIC, so no clot could be formed.