fibrinogeenia

Fibrinogenemia is a disorder of fibrinogen, the plasma glycoprotein essential for blood clot formation. Fibrinogen is synthesized in the liver; after vascular injury, thrombin converts soluble fibrinogen into insoluble fibrin, forming a hemostatic clot. Fibrinogen also influences platelet aggregation and wound healing. Aberrations can involve quantity, function, or both, leading to bleeding or, less commonly, thrombosis.

Congenital forms include afibrinogenemia (no measurable fibrinogen), hypofibrinogenemia (reduced levels), and dysfibrinogenemia (normal amount but dysfunctional fibrinogen). Most congenital defects are inherited in an autosomal recessive pattern (afibrinogenemia and many hypofibrinogenemias), while dysfibrinogenemia is typically autosomal dominant. Mutations commonly affect the FGA, FGB, or FGG genes encoding the fibrinogen chains.

Acquired reductions or dysfunctions of fibrinogen occur in liver disease, disseminated intravascular coagulation, massive transfusion, sepsis, and other consumptive or inflammatory states. Clinical presentation varies from mild or no symptoms to significant bleeding, particularly after trauma or surgery; dysfibrinogenemia can be associated with both bleeding and thrombosis. Pregnancy can be complicated by obstetric bleeding or placental issues in some congenital forms.

Diagnosis relies on laboratory testing. Fibrinogen concentration is measured (Clauss method), with parallel functional assays and coagulation screens (PT, aPTT, thrombin time). Genetic testing supports a diagnosis and informs family counseling.

Management depends on type and clinical scenario. Bleeding or surgery may require fibrinogen replacement with cryoprecipitate or fibrinogen concentrates, sometimes fresh frozen plasma, and antifibrinolytics. In pregnancy and during delivery, careful monitoring and maintenance of adequate fibrinogen levels are recommended. Prognosis and treatment plans are individualized.