Fibrinogen deficiency is caused by an absence/low levels of fibrinogen or dysfunctional fibrinogen.

May lead to bleeding or clotting events

Fibrinogen deficiency can be inherited (congenital) or acquired.

Two types of congenital fibrinogen deficiency:

• Type I deficiencies (quantitative abnormalities): Afibrinogenemia or Hypofibrinogenemia
• Type II deficiencies (qualitative abnormalities): Dysfibrinogenemia

Congenital fibrinogen deficiencies affect males and females equally.

Type I (quantitative abnormalities)

Afibrinogenemia:

• Complete absence of fibrinogen
• Increased bleeding, both spontaneous and traumatic
• Most severe form of congenital fibrinogen deficiency
• Accounts for 8-9% of all rare bleeding disorders

Hypofibrinogenemia:

• Less than normal plasma fibrinogen levels
• Bleeding largely associated with trauma or surgery (80%)

Type II (qualitative abnormalities)

Dysfibrinogenemia:

• Normal or low-normal plasma fibrinogen levels
• Largely asymptomatic (~50%), traumatic bleeding events

Bleeding manifestations in afibrinogenemia can range from mild to severe and can include:

• Nosebleeds
• Oral bleeding
• Joint and muscle bleeding
• Gastrointestinal bleeding
• Heavy menstrual bleeding
• Traumatic and surgical bleeding

In hypofibrinogenemia, bleeding episodes are usually mild; bleeding generally occurs following trauma or surgery.

Patients with congenital fibrinogen deficiency experiencing bleeding utilize fibrinogen replacement therapy to increase plasma fibrinogen levels.

Options for treatment include cryoprecipitate, fresh frozen plasma and fibrinogen concentrate.