Plasma Protein C and Antithrombin III Levels in Polycythemic Newborns

Thromboembolic complications have been reported in association with neonatal polycythemia, the primary cause of hyperviscosity in the newborn. Although there are some studies on coagulation in polycythemic neonates, the situations that predispose these newborns to thrombosis are still not clear.1 One of the causes may be the reduction in blood flow within the microcirculation, which favors coagulation. As protein C (PC) and antithrombin III (AT III) are important coagulation inhibitors, we decided to study them in polycythemic newborns.