Arterial Thrombosis of Unknown Etiology in a 10-Year-Old Male.

Arterial thrombotic events are exceedingly rare occurrences in pediatric populations. The incidence of childhood thrombosis is extremely low and the majority of cases are venous in origin. There are several well-known etiologies and genetic risk factors with an underlying predisposition to venous thrombosis, however, there have been few identified etiologies of arterial thrombotic events in pediatric patients. The most common include factor V Leiden mutation, trauma, neoplasm, and inherited metabolic disorders. This case report involves a 10-year-old male with no predisposing factors or significant medical or surgical history, who presents with a cerebral vascular accident secondary to a peripheral arterial clot of the basilar artery. The patient's only identifiable risk factor was an elevated factor VIII level. Elevated factor VIII levels are a risk factor for thrombotic events, with a greater impact on venous than on arterial thrombosis. However, due to a lack of international consensus on methods for the laboratory testing of factor VIII levels in plasma, it is not currently recommended that the measurement of factor VIII levels be part of routine thrombophilia screening in pediatric populations.