Thrombosis in neonates and children

The incidence of thrombosis is lower in children than in adults, however thrombosis related pediatric morbidity and mortality are significant. The incidence of thrombosis is maximum in neonates and during adolescence. The hemostatic system in the newborn differs from children and adults. Children till 6 months of age have lower levels of the vitamin-K–dependent coagulation factors II, IX, and X, compared to adults. Levels of thrombin inhibitors, such as antithrombin and heparin cofactor II, are similarly low at birth. Levels of protein C and S are low at birth. Protein S levels approach adult values by the age of 3-6 months, but protein C levels remain low even into childhood. Furthermore, plasminogen levels are low in newborns and infants. Thrombin generation is decreased (probably because of low prothrombin levels) and delayed in newborns compared with adults. There is a second peak of thrombosis during adolescence with more adult like risk factors In this article we will review the literature for pertinent clinical and management issues of experts in the field of neonatal and pediatric thrombosis. The material is presented in a manner that is to relevant to clinical practice.