CEREBRAL VENOUS THROMBOSIS AND ACTIVATED PROTEIN-C RESISTANCE

Background Activated protein C resistance (APC-R) due to factor V Leid en has recently been established as an important risk factor for cereb ral venous thrombosis (CVT). The clinical significance of abnormal or borderline functional APC-R in the absence of factor V Leiden is uncer tain. Our observations suggest that APC-R due to mechanisms other than factor V Leiden may also contribute to the development of CVT. Case D escriptions We describe three women who had superior sagittal and late ral sinus thrombosis while taking oral contraceptives and had a number of additional risk factors for CVT. Each had APC-R for different reas ons. Conclusions Inherited thrombophilia, including APC-R, should be l ooked for in all patients with CVT. Functional APC-R is a highly preva lent coagulopathy, but the reasons for this abnormality are diverse; a bnormal and borderline functional APC-R results should be supplemented by DNA analysis for the presence of factor V Leiden.