Ureteroceles are cystic dilatations of the distal submucosal or intravesical portion of a ureter. They are seen in about 1% to 2% of children who undergo cystoscopy, although the incidence in the general pediatric population is unknown. Ureteroceles frequently are associated with duplicated ureters (two ureters intersecting with the kidney). They may be located entirely within (intravesical) or outside the bladder (ectopic), at the bladder neck or urethra. The etiology of ureteroceles remains elusive. The current theory suggests that they derive from an intrinsic defect in the ureteral bud and from abnormal incorporation of the ureteral bud into the urethra and bladder.

Various anomalies are associated with ureteroceles, including duplicated ureters. Because of the potential association with duplicated ureters, renal ultrasonography should be undertaken in affected children to assess for hydronephrosis. In addition, contralateral vesicoureteral reflux or obstruction may occur. Finally, about 10% of ureteroceles may be bilateral.

Ureteroceles are the most common cause of urinary retention in females. They usually manifest in early childhood with symptoms suggesting infection of the urinary tract: fever, dysuria, foul-smelling urine, hematuria, and abdominal pain. If the ureterocele is located near or in the urethra, prolapse into the urethra may occur, resulting in urinary retention. 

Physical examination may reveal prolapse through the urethral meatus, but generally the urethra is normal. Although intravenous pyelography (IVP) is not as commonly performed since the advent of renal scans, it remains the gold standard for diagnosis of ureteroceles. IVP typically reveals a unilateral, complete ureteral duplication with mild hydronephrosis of the upper pole of the kidney or possibly only a lucent area in the bladder where the ureterocele is located. A bladder diverticulum also may be noted. Renal ultrasonography may reveal upper tract dilatation and an ureterocele in the bladder. Voiding  cystourethrography must be undertaken to determine the presence of associated vesicoureteral reflux. Computed tomography often detects a ureterocele, but it is a rather expensive alternative.

Treatment of ureteroceles depends on the age and general condition of the patient. If the ureterocele is intravesical, unilateral, and associated with minimal hydronephrosis of the ipsilateral kidney, simple excision with reimplantation of the ureter may be sufficient. If there is significant hydronephrosis of the affected kidney and renal function on the affected side (confirmed by renal scan) is greater than 25% of total function, pyeloureterostomy or ureteroureterostomy may be necessary to relieve the obstruction and hydronephrosis to preserve the remaining renal function of that kidney.

Urethral Prolapse

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