Fibrinogen (Fb) immunoassay determines Fb concentration and is useful in the diagnosis of Fb deficiency, or familial hypofibrinogenaemia (quantitative Fb deficiency) and dysfibrinogenaemia (qualitative Fb deficiency).
Hypofibrinogenaemia is characterised by low antigenic Fb concentration and can be caused by different Fb gene mutations. Although heterozygosity for a mutation might reduce Fb levels below the normal range, they do not usually produce a significant clinical condition unless inherited in the homozygous, or compound heterozygous state. In this case, afibrinogenaemia may result and lead to a serious bleeding condition.
Classical dysfibrinogenaemia results from impairment of fibrin polymerisation. Dysfibrinogenaemia is associated with prolonged thrombin clotting times and low functional Fb but usually normal antigenic Fb concentration. Dysfibrinogenaemia is most likely caused by mutation in the region of the Fb gene that codes for functional domains involved in polymerisation.
Acquired Fb deficiency can occur with increased consumption (disseminated intravascular coagulopathy or fibrinolytic therapy), reduced synthesis in severe liver disease, or haemodilution.
As fibrinogen is an acute phase protein, plasma levels increase in response to acute and chronic inflammation.
MOLP
Sample is suitable if frozen at -20 degrees celsius within 24 hours of collection.
Fibrinogen antigen
4 weeks
MPST