Persistence of right umbilical vein: a singular case.

Background. Persistent right umbilical vein (PRUV) is one of the most common prenatally detected venous anomaly. In the intrahepatic variant (I-PRUV) the right umbilical vein fuses with right portal vein and through the ductus venous drains into inferior vena cava, while in the uncommon extrahepatic variant (E-PRUV), the vein bypasses the liver completely. E-PRUV has a worse prognosis compared to I-PRUV, due either to severe hemodynamic effects or to the frequent association with other severe fetal malformations. Case. Here we report a case of E-PRUV with good outcome. Prenatal fetal ultrasonography (US) performed at 33 weeks of gestation in 28-year old woman, highlights the presence of E-PRUV with right UV draining in inferior vena cava. In the male neonate born at 35 weeks of gestation by C-section, the Apgar Score was 9(5')-10(10) and no other associated malformations and hemodynamic decompensation were found. Postnatal abdominal US showed the presence of enlarged paraumbilical veins. Conclusions. The association of E-PRUV draining into the inferior vena cava with shunt through paraumbilical veins, could have preserved offspring by severe cardiac overload, positively affecting prognosis.