Activated protein C resistance (APCR)

Resistance to activated protein C is the most common in Europe a congenital prothrombotic defect of hemostasis. Resistance of active coagulation factor V (Va) to activated protein C causes factor V to fail to undergo proteolytic degradation, leading to excessive thrombin production. In 95% of cases the cause is a point mutation in the factor V gene involving an switching between the amino acid arginine and glutamine; this is known as factor Leiden. Other very rare causes of resistance: the syndrome of antiphospholipid syndrome, increased factor VIII activity, oral hormonal contraception. Resistance to activated protein C increases the risk of developing venous thromboembolism. Each time in situation of detection of resistance to activated protein C in the test peroxidase test, the presence of the mutation should be confirmed by genetic testing genetic testing.