Inborn Prothrombotic States

Abstract

Genetic defects accounting for increased prothrombotic risk are related to antithrombin, prothrombin, protein C, protein S, and factor V. These defects can induce a wide array of clinical relevance and total a few hundred. Suspicion of the defect derives from clinical observation of spontaneous thrombosis either in the deep veins of the leg or in atypical sites (cerebral sinus, mesenteric hepatic veins) and/or at a young age ranging from intrauterine life (hence spontaneous abortion) until 50 years of age. The diagnosis can be frustrating because it requires combined techniques of hemostaseology and molecular biology and is therefore time- and resource-consuming, because only some of the above-mentioned events are associated with genetic defects, and not all identified carriers have the same risk. This reflects on their management, with recommendations for each condition at increased thrombotic risk, such as surgery, immobility, venous or arterial thromboembolism, and pregnancy.