Fibrinogen blood coagulation
Fibrinogen (citrate plasma, light blue tube)
What is being tested?
The test measures the amount of fibrinogen in the blood. Fibrinogen is a so-called coagulation factor, a protein that plays an important role in blood clotting. There are more than 20 different coagulation factors, all of which are produced by the liver.
In case of severe bleeding, a shortage of fibrinogen may occur which causes the bleeding to stop. In this case fibrinogen is administered in the form of donated blood products. In determining the amount of fibrinogen in the blood, only fibrinogen is measured and not the fibrin filaments that are formed from fibrinogen.
The test
When is this test done?
Fibrinogen is usually requested along with other coagulation tests. The doctor can then determine whether the patient is able to stop a bleed by sealing the wound with a blood clot.
A fibrinogen test is often requested as a follow-up to an abnormal prothrombin time(PT) or activated partial thromboplastin time(aPTT), in case of severe blood loss or for patients with an increased tendency to bleed.
Fibrinogen can also be requested to demonstrate active coagulation, and therefore consumption of fibrinogen, in critically ill (often intensive care) patients.
Fibrinogen is also used as a test to check the effect of anticoagulants. Anticoagulants are administered to patients who have had a heart attack or stroke due to a blood vessel being blocked by a blood clot. These drugs not only dissolve a clot, but also break down fibrinogen.
What does the result mean?
Normal
In healthy people, there is sufficient fibrinogen to form blood clots. In special cases, there is sufficient fibrinogen present, but the fibrinogen is not properly converted to fibrin due to a hereditary disease. This rare disorder is called dysfibrinogenemia.
Increased
Fibrinogen may be elevated in acute conditions, inflammation, cancer, myocardial infarction, stroke, trauma and surgery. This is because fibrinogen is a so-called acute phase protein. These are proteins that can be present in the blood in large quantities in the event of the aforementioned diseases. The amount of fibrinogen is normal again when the disorder has disappeared.
Lowered
When the amount of fibrinogen is reduced, there is not enough of this clotting factor to form blood clots.
Chronic shortage
Can be caused by afibrinogenemia and hypofibrinogenemia. Both conditions are hereditary and lead to a greatly reduced amount of fibrinogen in blood. Liver disease may also reduce the concentration of fibrinogen.
Acute shortage
Can be caused by extreme consumption of fibrinogen such as with massive blood loss, active clotting in all blood vessels and use of clot-dissolving drugs (anticoagulants).