Thrombosis and thrombophilia: principles for pediatric patients.

Thrombotic complications in pediatric patients are increasingly recognized due to increased use of invasive procedures, heightened awareness, improved imaging and prothrombotic lifestyle choices. Multiple risk factors are often present in pediatric patients with thrombosis. The most common risk factor is an indwelling catheter, followed by inflammatory conditions, malignancy, immobilization, thrombophilia and congenital heart disease. Rare severe thrombophilias, whether acquired or congenital, often present in children. Neonates have distinct patterns of thrombosis promoted by sepsis, inflammation, hypotension, hypoxia and the use of intravascular catheters in small caliber and umbilical vessels. Treatment of pediatric thromboembolic disease requires an understanding of developmental hemostasis, application of nonpediatric drug formulations and consolidation of expert guidelines and relevant adult literature. The acute and chronic consequences of thrombosis can be devastating in pediatrics and correlate with the length of time of vessel occlusion, underscoring the importance of rapid diagnosis and initiation of therapy. As trials begin to define recurrence risks, outcome predictors and optimal therapy for children with thrombosis and thrombophilia, consultation with an experienced pediatric hematologist provides the best available therapy today.