Fibrinogen deficiency

A rare blood disorder affecting clotting

Fibrinogen deficiency is a rare blood disorder characterized by the absence or low levels of fibrinogen, a protein essential for blood clot formation. This condition can lead to excessive bleeding or, in some cases, thrombosis. Fibrinogen deficiency can be inherited or acquired, with varying degrees of severity.

Types

Fibrinogen deficiency can be classified into three main types:

Afibrinogenemia

Afibrinogenemia is a severe form of fibrinogen deficiency where there is a complete absence of fibrinogen in the blood. It is usually inherited in an autosomal recessive manner. Individuals with afibrinogenemia often experience spontaneous bleeding episodes, which can be life-threatening.

Autosomal recessive inheritance pattern

Hypofibrinogenemia

Hypofibrinogenemia is characterized by lower than normal levels of fibrinogen. The symptoms are generally milder compared to afibrinogenemia, but patients may still experience bleeding problems, especially during surgery or after trauma.

Dysfibrinogenemia

Dysfibrinogenemia occurs when fibrinogen is present but dysfunctional. This can lead to either bleeding or thrombotic complications, depending on the nature of the fibrinogen abnormality.

Causes

Fibrinogen deficiency is primarily caused by genetic mutations affecting the fibrinogen genes (FGA, FGB, and FGG). These mutations can lead to reduced production or abnormal function of fibrinogen. Acquired fibrinogen deficiency can result from liver disease, disseminated intravascular coagulation (DIC), or certain medications.

Symptoms

The symptoms of fibrinogen deficiency vary depending on the type and severity of the condition. Common symptoms include:

• Excessive bleeding from cuts or injuries
• Spontaneous bleeding episodes
• Easy bruising
• Bleeding gums
• Heavy menstrual bleeding
• Joint bleeding

Diagnosis

Diagnosis of fibrinogen deficiency involves blood tests to measure fibrinogen levels and assess clotting function. Genetic testing may be performed to identify specific mutations in the fibrinogen genes. Additional tests, such as liver function tests, may be conducted to rule out acquired causes.

Treatment

Treatment for fibrinogen deficiency focuses on managing bleeding episodes and preventing complications. This may include:

• Fibrinogen replacement therapy using cryoprecipitate or fibrinogen concentrate
• Antifibrinolytic agents to prevent clot breakdown
• Regular monitoring and supportive care

Prognosis

The prognosis for individuals with fibrinogen deficiency varies. With appropriate management, many patients can lead normal lives. However, severe cases, particularly afibrinogenemia, may require lifelong treatment and careful monitoring to prevent bleeding complications.

Related pages

• Coagulation
• Hemophilia
• Von Willebrand disease