Test Type: 0.5 mL EDTA Plasma Kit Based
Stability Time:


Refrigerated: 2 days

Reference Range:
  • Optimal: <370 mg/dL
  • Borderline: 370-470 mg/dL
  • Increased Risk: >470 mg/dL


Fibrinogen or Factor I is an acute phase inflammatory plasma protein synthesized by the liver and is an essential component in the clotting cascade.



  • Fibrinogen is converted by thrombin to form fibrin, which is crosslinked with another protein in the final step in the formation of a blood clot.
  • Elevated levels are associated with inflammation.
  • Every 100 mg/dL increase in plasma fibrinogen level > 370 mg/dL has been associated with a 1.8 fold increased risk of CVD.1


  1. Fibrinogen Studies Collaboration. Danesh J, Lewington S, Thompson SG, et al. Plasma fibrinogen level and the risk of major cardiovascular diseases and nonvascular mortality: an individual participant meta-analysis. JAMA. 2005;294(14):1799-1809.

Collection Details:

Collection Instructions:

Preferred Specimen

0.5 mL EDTA plasma collected in plasma separator tube (Pearl Top)


Transport Temperature

Refrigerated (ship on frozen cold packs)