Fibrinogen Antigen

Other names: FIBRINOGEN ANTIGEN, NEPHELOMETRY, CARDIO IQ® FIBRINOGEN ANTIGEN, NEPHELOMETRY

Optimal result: 149 – 353 mg/dL

Fibrinogen is an acute-phase reactant, meaning that elevated fibrinogen levels can be seen the following conditions:

- Inflammation

- Tissue damage/trauma

- Infection

- Cancer

- Acute coronary syndrome

- Strokes

- Inflammatory conditions

Decreased fibrinogen levels (< 100 mg/dL) are associated with the following:

- Afibrinogenemia: Chronic

- Hypofibrinogenemia: Chronic

- End-stage liver disease: Chronic

- Severe malnutrition: Chronic

- Disseminated intravascular coagulation (DIC): Acute

- Abnormal fibrinolysis: Acute

- Large-volume blood transfusions: Acute

Fibrinogen is a soluble protein in the plasma that is broken down to fibrin by the enzyme thrombin to form clots.

Fibrinogen is a soluble protein that is produced in the liver and released into the bloodstream. When tissue or blood vessels are damaged, the coagulation cascade is initiated by platelets, and clotting factors are activated to the site as needed, one after another.

At the end of the cascade, fibrinogen is converted to fibrin. Fibrin is an insoluble protein that forms a threaded mesh over the injury site. Thrombin is the enzyme that activates this conversion.

The fibrinogen test is used to investigate certain bleeding or clotting abnormalities, as follows:

- Bleeding disorder

- Thrombotic events

 - Suspected DIC

- Abnormalities in coagulation panel (PT/PTT)

- Follow-up in chronic conditions such as liver disease

- Dysfibrinogenemia, in which a fibrinogen antigen test is performed to differentiate lack of protein in the system or just dysfunctional fibrinogen

- Occasionally used for screening risk of coronary artery disease

Normal fibrinogen activity results usually reflect normal blood-clotting ability.

 

Fibrinogen Antigen
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