Factor V Assay, Plasma

Factor V is a large single-chain glycoprotein composed of 3 homologous.A-type domains. Approximately 20% of factor V in the blood is compartmentalised in platelet a-granules. Thrombin is the physiological activator of factor V. The active form of factor V enhances the activation of prothrombin by several thousand-folds. Congenital factor V deficiency (parahaemophilia) is a rare disorder. It is inherited in an autosomal recessive manner, and the patients suffer a moderate to severe bleeding disorder. Additional molecular defects in the factor V gene have been identified in patients with “pseudo-homozygosity” for factor V Leiden (the Leiden allele plus the null allele). These patients may be identified on the basis of thrombotic problems.

This test is useful in the differential diagnosis of bleeding disorders. Most factor V- deficient patients have low factor V activity and antigen level; however, discrepancy between functional and antigenic levels has also been described. Acquired factor V deficiency can be associated with amyloidosis.

2 ml Citrate Plasma Frozen

By Report