Venous thromboembolism in childhood: A prospective two-year registry in The Netherlands

Objective: To study the incidence, signs and symptoms, diagnostic tests, risk factors, therapy, and complications of pediatric venous thromboembolism (VTE) in The Netherlands. Methods: A prospective 2-year registry of VTE in children aged >18 years. Results: Ninety-nine patients were registered. The annual incidence of VTE was 0.14/10,000 children, 35% of whom were symptom free. Almost half of the patients were newborns. Neonatal VTE was almost exclusively catheter related, located in the upper venous system, and asymptomatic. In older children VTE was catheter related in approximately one third and more often was located in the lower venous system. In 85% of all patients, thrombosis developed while the patient was in the hospital. Diagnosis was usually made by ultrasonography. In 98% of all patients, at least 1 risk factor was present. Congenital prothrombotic disorders were more often present in older children (21%) than in neonates (6%). A variety of treatment modalities were used. Morbidity consisted of bleeding (7%) and recurrent thrombosis (7%). Two children died as result of VTE. Conclusion: VTE is mostly diagnosed in hospitalized children, especially sick newborns with central venous catheters and older children with a combination of risk factors. Primary prevention, optimal treatment, and long-term outcome of pediatric symptomatic and asymptomatic VTE need to be studied.