Factor Deficiencies

Overview of Coagulation Factor Deficiencies

• Definition: A group of bleeding disorders caused by a deficiency or dysfunction of one or more coagulation factors, which are essential for the normal blood clotting process
• Classification:
  • Hereditary (Inherited) Coagulation Factor Deficiencies: Genetic disorders caused by mutations in genes encoding coagulation factors
  • Acquired Coagulation Factor Deficiencies: Caused by external factors that impair coagulation factor synthesis or function
• Clinical Features:
  • Bleeding Tendency: The severity of bleeding depends on the specific factor involved and the degree of deficiency
  • Common Manifestations:
    • Easy bruising
    • Prolonged bleeding after cuts, dental procedures, or surgery
    • Nosebleeds (epistaxis)
    • Gum bleeding
    • Menorrhagia (heavy menstrual bleeding) in women
    • Hemarthrosis (bleeding into joints)
    • Intracranial hemorrhage (rare but life-threatening)

Hereditary Coagulation Factor Deficiencies

• General Characteristics:

  • Inherited in an autosomal recessive or X-linked recessive pattern
  • Often present with bleeding symptoms early in life
  • Specific diagnosis requires factor assays

• Hemophilia A (Factor VIII Deficiency):

  • Definition: An X-linked recessive bleeding disorder caused by a deficiency of Factor VIII (FVIII)

• Hemophilia B (Factor IX Deficiency, Christmas Disease):

  • Definition: An X-linked recessive bleeding disorder caused by a deficiency of Factor IX (FIX)

• Other Rare Hereditary Factor Deficiencies:

  • Factor XI Deficiency (Hemophilia C):
  • Factor V Deficiency:
  • Combined Factor V and VIII Deficiency
  • Factor VII Deficiency:
  • Factor X Deficiency:
  • Factor XIII Deficiency:

Acquired Coagulation Factor Deficiencies

• Vitamin K Deficiency:
  • Pathophysiology: Vitamin K is a cofactor for the carboxylation of glutamate residues on Factors II (prothrombin), VII, IX, and X, as well as proteins C and S
• Liver Disease:
  • Pathophysiology: The liver is the primary site of synthesis for most coagulation factors
• Disseminated Intravascular Coagulation (DIC):
  • Definition: A complex disorder characterized by widespread activation of coagulation and fibrinolysis, leading to both thrombosis and bleeding

Key Terms

• Coagulation Factors: Proteins involved in the coagulation cascade
• Hemophilia A: Factor VIII deficiency
• Hemophilia B: Factor IX deficiency
• Vitamin K: A cofactor for the carboxylation of certain coagulation factors
• Liver Disease: Impairs the synthesis of coagulation factors
• Disseminated Intravascular Coagulation (DIC): A consumptive coagulopathy with widespread clotting and bleeding
• Prothrombin Time (PT): Test of the extrinsic and common pathways
• Activated Partial Thromboplastin Time (aPTT): Test of the intrinsic and common pathways