Fibrinogen Degradation Products (FDP), Plasma
This assay is used to detect and semi quantitatively measure the presence of FDP in plasma.
Fibrinolysis is the enzymatic breakdown of fibrin in blood clots. Plasmin cuts the fibrin mesh at various places, leading to the production of circulating fragments that are cleared by other proteases. Primary fibrinolysis is a normal body process. The fibrinolytic system serves to limit the formation of thrombi and to facilitate healing or recanalization of a vessel with a thrombotic occlusion. Secondary fibrinolysis is the breakdown of clots due to medicine, disorder, or other cause.
Under normal conditions, the fibrinolytic process is localized on the fibrin clots because alpha2-antiplasmin and the plasminogen activator inhibitors prevent fibrinolysis from spreading. Fibrin Degradation Products (FDP) that occur are very heterogeneous and include products derived from fibrin, soluble complexes, degradation products from fibrinogen, and from nonstabilized fibrin. The presence FDP of in plasma can provide important information for the diagnosis of hemostatic disorders. An abnormal fibrinolytic and/or fibrinogenolytic activity shown by high levels of FDP in plasma can be found in clinical states, such as eclampsia, carcinoma (promyelocytic leukemia), cardiac and renal disorders, hepatic disorders, fibrinolysis, pulmonary embolism, deep vein thrombosis (DVT), following surgery or trauma, and after lytic therapy.
Increased FDPs are seen in primary fibrinolysis as well as during fibrin clot breakdown. Elevated FDP levels are a hallmark finding in disseminated intravascular coagulation (DIC). Elevated FDP levels are not specific for DIC and increased FDP levels are often seen in primary fibrinolysis, severe liver disease, including alcoholic cirrhosis, eclampsia, during acute thrombotic episodes.
Blue-top (sodium citrate) tube
Blood should be collected in a blue-top tube containing 3.2% buffered sodium citrate. Evacuated collection tubes must be filled to completion to ensure a proper blood-to-anticoagulant ratio. The sample should be mixed immediately by gentle inversion at least six times to ensure adequate mixing of the anticoagulant with the blood. A discard tube is not required prior to collection of coagulation samples unless the sample is collected using a winged (butterfly) collection system. With a winged blood collection set a discard tube should be drawn first to account for the dead space of the tubing and prevent under-filling of the evacuated tube. When noncitrate tubes are collected for other tests, collect sterile and nonadditive (red-top) tubes prior to citrate (blue-top) tubes. Any tube containing an alternative anticoagulant should be collected after the blue-top tube. Gel-barrier tubes and serum tubes with clot initiators should also be collected after the citrate tubes. To avoid delays in turnaround time when requesting multiple tests on frozen samples, please submit separate frozen specimens for each test requested.