Congenital afibrinogenemia

Definition

Congenital afibrinogenemia is a rare, inherited blood disorder in which the blood does not clot normally due to a lack of or a malfunction involving fibrinogen, a protein necessary for coagulation.

Causes, incidence, and risk factors

This rare disease is caused by an autosomal recessive gene, which requires inheritance of the abnormal gene from both parents. There may be either a complete lack of fibrinogen or a defect in the functioning of available fibrinogen. This condition can occur in both sexes. The main risk factor is a family history of bleeding disorders.

Symptoms

• Bruising
  
• Nosebleeds
  
• Excessive bleeding following injury or surgery
  
• Gastrointestinal bleeding
  
• Bleeding in joints
  
• Miscarriage
  

Signs and tests
If a bleeding disorder is suspected, laboratory tests are performed to determine the type and extent. This disorder usually shows up in childhood, often at birth.

Tests include:

• PTT
  
• Prothrombin time (PT)
  
• Clotting time
  
• Fibrinogen levels
  
• Thrombin time
  
• Reptilase time
  
• Bleeding time
  

All of these tests are abnormal in afibrinogenemia.

Treatment

Patients may be transfused with plasma (the liquid portion of the blood) or cryoprecipitate (a blood product containing concentrated fibrinogen) to treat bleeding episodes or in preparation for surgery needed to treat other conditions. People with this condition should be immunized with the hepatitis B vaccine because of the increased risk of developing hepatitis due to transfusion.

Expectations (prognosis)

Significant bleeding is common with this condition and these episodes may be severe, even fatal. Bleeding in the brain is a leading cause of death in patients with this disorder.

Complications

• Bleeding from the umbilical cord
  
• Bleeding from the mucous membranes
  
• Gastrointestinal bleeding
  
• Intracranial bleeding
  
• Clotting with treatment