Sickle cell disease: an inherited thrombophilia.

Activation of the hemostatic system occurs in patients with sickle cell disease. The extent to which this activation contributes to sickle cell pathophysiology is uncertain. Clinical trials of anticoagulants or platelet inhibitors have demonstrated the ability to decrease biomarkers of hemostatic activation, but this has generally not resulted in improvement in clinically relevant outcomes. Venous thromboembolism (VTE: deep venous thrombosis and pulmonary embolism) has been until recently an underappreciated complication of sickle cell disease, with incident event and recurrence rates consistent with a strong thrombophilia. There is no strong evidence that management should differ than for other patients with VTE, with the possible exception that secondary prophylaxis be extended regardless of provocation, given the persistent strong thrombophilic state.