Specimen Information

Type

Blue, Citrate

Volume

1.0 ml

Transport Info

Promptly centrifuge 15 minutes
Carefully transfer plasma portion of specimen to separate plastic tube using a plastic pipette
Frozen

Fasting Required?

False

Clinical Significance

Fibrinogen is a glycoprotein with a molecular weight of 340,000. It is composed of two peripheral areas, D and a central domain, E.
In vivo, thrombin converts plasma fibrinogen into insoluble fibrin, the fibrin clot being stabilized by Factor XIII. Plasmin splits fibrinogen as well as fibrin into various degradation products. The fragments X and Y constitute the early split products from fibrinogen and from non-crosslinked fibrin. Fragments D and E are the late split products. The degradation of the stabilized fibrin by plasmin leads to the formation of complexes named C-oligomers (YXD/DYX, YY/DXD, DY/YD, and finally to the terminal product D-dimer.
Under normal conditions, the fibrinolytic process is localized on the fibrin clot, since alpha-antiplasmin and the plasminogen activator inhibitors prevent fibrinolysis from spreading. During disseminated intravascular coagulation (DIC), fibrinolysis spreads and becomes systemic, in which case the degradation of circulating fibrinogen will occur. Fragments that are produced are very heterogeneous: products derived from fibrin, soluble complexes, degradation products from fibrinogen and from non-stabilized fibrin.
An abnormal fibrinolytic and/or fibrinogenolytic activity shown by high levels of FDP in plasma can also be found in clinical states, such as: eclampsia, alcoholic cirrhosis, carcinoma (promyelocytic leukemia), post-operative complications, cardiac, renal, and hepatic disorders, fibrinolysis, pulmonary embolism, and deep vein thrombosis (DVT).
A persistently elevated level of FDP indicates that the fibrinogenolytic or fibrinolytic process is continuing and suggests that the causative agent continues to exert its effect.