hematology and oncology
Factor V Resistance to Activated Protein C (APC)
Diagnosis of Factor V Resistance to APC
Plasma coagulation assay Diagnosis is based on The activated protein C resistance assay Genetic mutation analysis of the factor V gene using DNA-based assays The activated protein C resistance assay is a screening test for the presence of factor V Leiden. Activated protein C is added to a 5-fold dilution of patient plasma, and the coagulation time is measured. In patients with homozygous or heterozygous factor V Leiden resistance, the prolongation of the clotting time is significantly reduced because their factor V is resistant to cleavage by activated protein C. Confirmation of factor V Leiden is then done by DNA-based testing for the mutation. 