Prethrombotic disorders in children with arterial ischemic stroke and sinovenous thrombosis.

BACKGROUND Arterial ischemic stroke (AIS) and sinovenous thrombosis (SVT) are relatively rare events in children. The contribution of prethrombotic disorders to the etiology of these entities has not been completely elucidated. OBJECTIVES To determine the frequency of inherited and acquired prethrombotic disorders in a pediatric population with AIS and SVT and to report clinical and radiological features. METHODS From May 1992 to April 1997, 30 consecutive children with AIS and 10 children with SVT were assisted at a single institution. Hemostatic evaluation was performed for all the children. Evaluation included the following assays: protein C, protein S, antithrombin, plasminogen, activated protein C resistance, factor V Leiden mutation, and the detection of antiphospholipid antibodies. Data concerning baseline demographics, risk factors, presenting features, family history of thrombosis, and radiological findings were also recorded. RESULTS One or more prethrombotic disorders were present in 9 children (30%) with AIS (inherited protein S deficiency, 2 patients; inherited protein C deficiency, 1 patient; acquired antithrombin deficiency, 2 patients; antiphospholipid antibodies, 3 patients; and antiphospholipid antibodies and plaminogen deficiency, 1 patient) and in 5 children (50%) with SVT (inherited protein S deficiency, 1 patient; acquired antithrombin deficiency, 3 patients; and antiphospholipid antibodies, 1 patient). CONCLUSIONS Most children studied presented both a variety of risk factors for thrombosis and concomitant prethrombotic disorders. Therefore, a complete hemostatic evaluation for all children with AIS and SVT should be performed, despite the presence of obvious clinical risk factors or lack of family history of thrombosis.