Clinical importance and evidence of APC-resistance

Less than twenty-five percent of cases with recurrent thrombotic episodes h ad been identified to be associated with inherited defects of hemostasis, b efore Dahlbeck et al. described the congenital resistance towards activated protein C in 1993. With an incidence of about 5% of the population, APC-re sistance caused by the Factor V Leiden Mutation is the most important hered itary thrombophilic rise factor in Europe. Of all patients with a familiar trace of thrombophilic tendency, up to 40% are carriers of this defect. In addition to molecular methods and in contrast to the original functional me thod described by Dahlbeck, nowadays, simple tests allow fast and reliable detection of heterocygous or homocygous mutations of Factor V Leiden. Scree ning for additional hereditary or acquired thrombophilic rise factors seems to be important for the estimation of an individual patient's risk and for the establishment of a strategy of primary or secondary antithrombotic pro phylaxis in a patient.