Afibrinogenemia; Hypofibrinogenemia; Dysfibrinogenemia; Factor I deficiency
Congenital fibrinogen deficiency is a very rare, inherited blood disorder in which the blood does not clot normally. It affects a protein called fibrinogen. This protein is needed for the blood to clot.
This disease is due to abnormal genes. Fibrinogen is affected depending on how the genes are inherited:
- When the abnormal gene is passed down from both parents, a person will have a complete lack of fibrinogen (afibrinogenemia).
- When the abnormal gene is passed down from one parent, a person will have either a reduced level of fibrinogen (hypofibrinogenemia) or a problem with the function of fibrinogen (dysfibrinogenemia). Sometimes, these two fibrinogen problems can occur in the same person.
People with a complete lack of fibrinogen may have any of the following bleeding symptoms:
- Bruising easily
- Bleeding from the umbilical cord just after birth
- Bleeding in the mucous membranes
- Bleeding in the brain (very rare)
- Bleeding in the joints
- Heavy bleeding after injury or surgery
- Nosebleeds that do not stop easily
People with a reduced level of fibrinogen bleed less often and the bleeding is not as severe. Those with a problem with the function of fibrinogen often don't have symptoms.