In addition, severe transient deficiencies of antithrombin III, protein C and protein S in sick newborn infants increase the risk of vascular thrombosis. 6,7 Neonatal thrombosis is a serious event that can cause mortality or result in severe morbidity and disability. 8 Umbilical catheterization is identified as a risk factor of vascular thrombosis in neonates. 5 Thrombosis was also seen in the absence of vascular catheterization. In this study, there was a history of UVC insertion in all infants with venous thrombosis and three with an arterial one.
Thrombosis can occur without history of umbilical catheter insertions, as in two of our patients.
Preterm infants are more prone to catheter-related thrombosis because of the slow flow rate of infusion, the larger size of the catheter in comparison to the size of the vessel, which may occlude the vessel, and the longer period these catheters are kept in these sick preterm infants. In our study, six infants were premature and all had umbilical catheterization. Doppler ultrasonography is the most useful and most popular method of diagnosis of neonatal thrombosis, however, its diagnostic accuracy remains uncertain. 10 Angiography is the best method for confirming the diagnosis. In this study, angiography was used in only three infants, and the remaining were diagnosed by ultrasonography.