Acquired Coagulation Disorders

DIC (Disseminated Intravascular Coagulation)

• Considered an acquired bleeding disorder, not a disease entity
• Abnormal acceleration of the coagulation cascade results in thrombosis and simultaneous hemorrhage
• Paradoxical clinical presentation: clotting and hemorrhage
• Results in depletion of clotting factors

Acquired Coagulation Disorders

• Coagulation deficiency caused by antibodies (e.g., factor VIII autoantibodies)
• Occurs rarely, with an incidence of approximately 1 per million per year
• Treatment consists of immunosuppression and factor replacement

Massive Transfusion Syndrome

• Defined as transfusion of more than 1.5 times the patient's blood volume in 24 hours
• Results in acquired coagulopathy due to dilution of plasma and platelets and excess anticoagulant
• Prevention: administer 1 unit FFP and calcium chloride for every 4-6 units of PRBCs

Disorders of Platelet Function

• Hyperglobulinaemia: associated with multiple myeloma or Waldenström's disease, causing interference with platelet adherence, release, and aggregation
• Myeloproliferative and myelodysplastic disorders: intrinsic abnormalities of platelet function
• Uraemia: associated with various abnormalities of platelet function

Hereditary Coagulation Disorders

• Hereditary deficiencies of each of the coagulation factors have been described
• Haemophilia A (factor VIII deficiency), haemophilia B (factor IX deficiency), and von Willebrand disease are the most frequent
• Other deficiencies (e.g., fibrinogen, prothrombin, factors V, VII, X, XI, XIII) are rare
• Inheritance is autosomal recessive, except for factor XI deficiency
• Recombinant factor VIIa is available for therapy

Factor XI Deficiency

• Seen mainly in Ashkenazi Jews, occurring in either sex
• Bleeding risk shows incomplete correlation to the severity of the deficiency
• Bleeding occurs after trauma, such as surgery
• Treatment is with fibrinolytic inhibitor, factor XI concentrate, or fresh frozen plasma (FFP)

Factor XIII Deficiency

• Produces a severe bleeding tendency, characteristically with umbilical stump bleeding
• Plasma concentrates and recombinant preparations of factor XIII are available