Urinary Ascites and Transient Intestinal Obstruction in a Preterm Infant: An Interesting Case of Posterior Urethral Valve.

Posterior urethral valve (PUV) is the most common congenital cause of bladder outflow obstruction in male neonates. We report a preterm neonate with PUV who presented as nonimmune fetal hydrops with intestinal obstruction in the antenatal period. The mother of our patient is a 33-year-old woman who started her prenatal care at our hospital at 30 weeks' gestation. Her sonogram done at 32 weeks in our hospital revealed fetal hydrops. It showed polyhydramnios, mild pyelectasis of right kidney, normal left kidney, and fetal ascites. Amniocentesis revealed bile stained amniotic fluid. Ultrasound during the procedure showed dilated fetal bowel loops with increased echoes. Following delivery at 32 weeks postnatal exam showed ascites with absence of skin edema, pleural, or pericardial effusion. The abdominal sonogram showed distended urinary bladder and bilateral hydroureteronephrosis. Bladder catheterization was done which relieved the bladder outlet obstruction. Voiding cystourethrogram was done later which confirmed PUV and bilateral grade 5 vesicoureteral reflux. The formation of urinary ascites in PUV serves as a pop-off mechanism to relieve the intravesical and intrarenal pressure. When this happens by mechanisms other than bladder rupture, it can lead on to transient intestinal obstruction and hepatic synthetic defects.