Ross M. Decter, MD, FRCS
Paul H. Smith III, MD
BASICS
DESCRIPTION
• Ureterocele is a cystic dilation of the terminal/intravesical ureter.
• May be classified based on anatomic location:
– Intravesical: Contained entirely within the bladder above the bladder neck; seen frequently in single system ureteroceles.
– Extravesical (Ectopic): Some portion of ureterocele permanently located at the level of the bladder neck or urethra; seen frequently in duplex system ureteroceles.
• Descriptive classification:
– Cecoureterocele: Ureterocele extends into urethra, but orifice within the bladder
– Sphincteric
– Stenotic
– Sphinctero-stenotic
– Blind
– Nonobstructive
• Most ureteroceles are associated with the upper pole of a duplex collecting system and are usually ectopic
• Today many ureteroceles are detected during routine prenatal screening ultrasounds
• When discovered in adults they are rarely of clinical consequence.
EPIDEMIOLOGY
Incidence
1 in 500 to 1 in 4,000
Prevalence
As high as 1 in 500 (autopsy study)
RISK FACTORS
• More common in girls (5–7:1)
• More common in whites
• Bilateral in 10–15% of cases
• Extravesical ureteroceles associated with upper pole of duplex system often diagnosed in infancy or childhood
Genetics
Likely multifactorial inheritance
PATHOPHYSIOLOGY
• Several hypotheses:
– During embryogenesis, the mesonephric duct and the distal ureteral bud incorporate into the anterior cloaca/urogenital sinus. Chawalla membrane breaks down allowing the incorporation of the distal ureter into the developing bladder. Incomplete breakdown of Chwalla membrane is thought to be one cause of the ureterocele.
– Delay in canalization of lumen of ureteral bud is another theory.
ASSOCIATED CONDITIONS
• Duplicated collecting system: 80%
• Single system: 20%
– Most common type in boys, but uncommon in girls (5%)
• Vesicoureteral reflux (VUR)
– Ipsilateral lower pole in duplex system: 50–70%
– Contralateral kidney: 10–30%
GENERAL PREVENTION
Antibiotic prophylaxis in patients at risk for upper-tract infection (VUR or obstruction)
DIAGNOSIS
HISTORY
• Prenatal hydronephrosis
• UTI/sepsis/failure to thrive
• Hematuria
• Bladder outlet obstruction
– Most common cause of bladder outlet obstruction in newborn girls
• Intralabial mass (prolapsed ureterocele)
PHYSICAL EXAM
• Abdominal mass (hydronephrosis)
• Intralabial prolapsing cystic mass
– Often appear congested and dusky
– Smooth-walled appearance helps differentiate from sarcoma botryoides; other causes can include urethral prolapse and urethral caruncle
DIAGNOSTIC TESTS & INTERPRETATION
Lab
• Serum creatinine
• Urinalysis
• Urine culture
Imaging
• Renal/bladder US:
– Prenatal hydronephrosis
– Thin-walled intravesical cystic structure or septations in the bladder
– Hydroureteronephrosis
– Duplex collecting system with dilated upper pole
• Voiding cystourethrogram (VCUG)
– Smooth, broad based filling defect near trigone
– Critical to image during early filling
May efface as bladder fills
• Renal scintigraphy
– DMSA
Evaluate renal parenchyma for scarring, differential function
– MAG-3
Evaluate drainage to determine extent of obstruction, differential function
• IVP:
– Cobra-head sign in the bladder when contrast fills the ureterocele (not usually performed) (1)
Diagnostic Procedures/Surgery
• Cystoscopy
– Findings vary, but best seen with partially empty bladder
Pathologic Findings
• Abnormal or absent musculature of distal ureter
• Renal dysplasia
– Seen in ∼40–70% of upper-pole moieties with ureterocele; more common in association with extravesical ureteroceles
DIFFERENTIAL DIAGNOSIS
• Bladder polyps
• Ectopic ureter
• Edema
• Mesonephric duct cyst
• Tumor
• Urethral prolapse
TREATMENT
GENERAL MEASURES
Surgical treatment is needed in most cases
MEDICATION
First Line
• Culture directed antibiotics for treatment of UTI/Sepsis
• Antimicrobial prophylaxis until reflux or obstruction repaired in children:
– Amoxicillin: 5–7 mg/kg/d as neonate
– Trimethoprim-sulfamethoxazole: 2 mg/kg/d OR nitrofurantoin 1–2 mg/kg/d beyond 2 mo of age
Second Line
Endoscopic incision if acutely septic
SURGERY/OTHER PROCEDURES
• Endoscopic transurethral incision:
– Usually effective in relieving obstruction
– Risk of developing reflux in that system
– Outpatient procedure
– Effective for intravesical and single-system ureteroceles, less so for extravesical ureteroceles (2)[B]
– Can be a temporizing measure until definitive repair (2)[B]
• Formal surgical repair
– Definitive treatment but higher morbidity
– Goals of surgery: Preserve functional renal parenchyma, relieve obstruction, correct reflux
– Upper-pole heminephrectomy if dilated non-functioning upper pole
– Ureteroureterostomy if upper pole is functional and no lower pole reflux
– Ureterocele excision and common sheath reimplatnation if reflux is present (3)[B]
ADDITIONAL TREATMENT
Radiation Therapy
N/A
Additional Therapies
Observation if asymptomatic; no or mild reflux or obstruction
Complementary & Alternative Therapies
N/A
ONGOING CARE
PROGNOSIS
Depends on extent of obstruction, infections, and presence or absence of renal dysplasia
COMPLICATIONS
• The major complication in adults and children is ureteral obstruction (4)
• Sepsis, loss of renal function
• Incontinence (primary or secondary)
• Persistent dilation of ureteral stump
• Persistent VUR
FOLLOW-UP
Patient Monitoring
• Renal and bladder US
• VCUG to diagnose/follow-up VUR
• Monitor renal function if bilateral
• Treat UTI
Patient Resources
• MedlinePlus: Ureterocele. http://www.nlm.nih.gov/medlineplus/ency/article/000462.htm
• Urology Care Foundation: Ureterocele. http://www.urologyhealth.org/urology/index.cfm?article=42
REFERENCES
1. Palmer L. Pediatric urologic imaging. Urol Clin N Am. 2006;33(3):209–423.
2. Adorlslo O, Elia A, Landi L, et al. Effectiveness of primary endoscopic incision in treatment of ectopic ureterocele associated with duplex system. Urology 2011;77:191–194.
3. Beganovi A, Klijn AJ, Dik P, et al. Ectopic ureterocele: Long-term results of open surgical therapy in 54 patients. J Urol. 2007;175:251–254.
4. Coplen DE, Duckett JW. The modern approach to ureteroceles. J Urol. 1995;153:166–171.
ADDITIONAL READING
• Byun E, Merguerian PA. A meta-analysis of surgical practice patterns in the endoscopic management of ureteroceles. J Urol. 2006;176:1871–1877.
• Husmann D, Strand B, Ewalt D, et al. Management of ectopic ureterocele associated with renal duplication: A comparison of partial nephrectomy and endoscopic decompression. J Urol. 1999;162:1406.
See Also (Topic, Algorithm, Media)
• Bladder Mass
• Collecting System, Complete Duplication
• Hydronephrosis/Hydroureteronephrosis (Dilated Ureter/Renal Pelvis), Pediatric
• Hydronephrosis/Hydroureteronephrosis (Dilated Ureter/Renal Pelvis), Prenatal
• Ureterocele Image 
• Vesicoureteral Reflux, Pediatric
CODES
ICD9
• 593.70 Vesicoureteral reflux unspecified or without reflux nephropathy
• 593.89 Other specified disorders of kidney and ureter
• 753.23 Congenital ureterocele
ICD10
• N13.70 Vesicoureteral-reflux, unspecified
• N28.89 Other specified disorders of kidney and ureter
• Q62.31 Congenital ureterocele, orthotopic
CLINICAL/SURGICAL PEARLS
• Early filling x-rays during VCUG mandatory to enhance detection of ureterocele.
• Choice of treatment driven by acuity of illness, degree of obstruction, VUR, and degree of renal dysplasia.
• Definitive endoscopic treatment most successful for single-system ureteroceles.