Abstract

Aureterocele is a rare urologic disorder characterized by cystic dilatation of the distal ureter. In about 80% of cases, this condition comprises the ureter draining the upper pole of a duplex collecting system. Because the ureteric orifice is located distal to the trigone and is often stenotic or obstructed by the closed bladder neck, the proximal ureter and its corresponding renal pelvis become dilated, leading to varying degrees of dysplasia of the upper pole moiety. Ureteroceles vary in size from small, clinically asymptomatic lesions to large lesions, which can obstruct the ipsilateral and contralateral ureters and prolapse into the urethra, causing bladder outlet obstruction. In the pediatric population, ureteroceles are found in approximately 1 per 4000 infants, are 4 to 7 times more frequent in girls, affect predominantly the white population, have a slight left-sided preponderance, and are bilateral in 10% of cases. Ureteroceles have been increasingly diagnosed in utero by means of sonography. However, the exact incidence in the fetus is difficult to determine, although an estimation of 1 per 5000 to 9000 live births has been quoted recenty. On the basis of this information, bilateral fetal ureteroceles are therefore expected in 1 or 2 per every 100,000 fetuses. Not surprisingly, reports on the prenatal diagnosis and implications of bilateral ureteroceles are scarce. In this report, the prenatal sonographic findings, natural history, and subsequent management of a case of bilateral fetal ureteroceles are described.