Favorable Obstetric Outcome in a Fetus Diagnosed With Umbilical Vein Varix at 22 Weeks' Gestation

Abstract

Umbilical vein varix (UVV) is a rare diagnosis during early gestation, and most cases diagnosed early have a poor obstetric outcome. We report a case of intraabdominal extrahepatic UVV diagnosed at 22 weeks of gestation by ultrasonography, with a favorable obstetric outcome. This case shows that early diagnosis of UVV during pregnancy does not necessarily correlate with poor outcome. Pregnancy termination is thus not the only option, and an affected pregnancy can be carried to term under close monitoring if there are no other associated anomalies. Variceal dilatation of the umbilical vein is rare and accounts for approximately 4% of malformations of the umbilical cord [1]. UVV has been defined variously; Sepulveda et al [2] defined fetal intra-abdominal UVV (FIUVV) as an intra-abdominal umbilical vein diameter at least 1.5 times greater than the diameter of the intrahepatic umbilical vein, while Allen et al [3] defined the anomaly as an intra-abdominal umbilical vein diameter exceeding 9 mm. Syphilis, degenerative changes, decreased resistance due to icterus, and congenital thinning have been proposed as etiologies of FIUVV. The most likely etiology and the only pathologic finding in most cases is thinning of the vessel wall near the anterior abdominal wall due to intrinsic weakness of the umbilical vein wall [4]. FIUVV is associated with a fetal death rate of up to 44%, and with karyotype abnormalities in 12% of cases (trisomy 21, 18 and 9, and triploidy 69,XXX). Structural malformations and hydrops fetalis have been diagnosed in up to 35% of cases each [2,5,6]. Our case of UVV is unique in having a favorable obstetric outcome, despite being diagnosed at an early gestational age of 22 weeks. A 24-year-old primigravida attended a routine antenatal ultrasound at 22 weeks of gestation. A cystic structure (15 × 14 mm) was detected in the fetal abdomen, just beneath the abdominal wall at the level of liver (Figure A). Color Doppler examination revealed it to be vascular in nature with the umbilical vein leading to it, suggesting a diagnosis of extrahepatic FIUVV (Figure B). Doppler examination allowed differentiation of UVV from other cystic lesions, including choledochal cyst, liver cyst, urachal cyst and mesenteric cyst. A careful scan failed to detect any other associated anomalies. Fortnightly ultrasound scans were performed to monitor growth of the fetus until 34 weeks’ gestation. During this period, there was no change in the size of the cyst. The patient was temporarily lost to follow-up. She was then reported again after a normal term delivery by a trained nurse at home. The perinatal period was uneventful. There was no family history of any similar anomaly or any features of isoimmunization. Because of the absence of any associated anomalies, karyotyping was not performed. Ultrasound examination at 3 months was normal. The child was healthy after 1 year. UVV presents in approximately 4% of malformations of the umbilical cord [1], and is more common in the umbilical cord than in the fetus [7]. In intraabdominal UVVs, extrahepatic varices are more common than intrahepatic ones [6]. Approximately 100 cases have been reported in the