What Is a Ureterocele?
Updated: 3 days ago
Medically reviewed by Dr. Baraa Alnahhal, MD · Last reviewed: October 2026
Quick Answer: What Is a Ureterocele?
A ureterocele is a condition in which the end of a ureter does not form correctly and swells where it enters the bladder, blocking urine drainage and possibly letting urine back up into the kidneys. It affects approximately 1 in 5,000 to 12,000 children, more often females, and is typically treated with minimally invasive or reconstructive surgery. [1]
What the research says
Ureteroceles are often found before birth, and prenatal ultrasound is accurate. In a meta-analysis of 11 studies covering 284 fetuses with a prenatal diagnosis of a duplex kidney collecting system, a ureterocele was present on ultrasound in 70.7% of cases, the prenatal diagnosis was confirmed after birth in 90.9%, and after birth 51.3% of children had vesicoureteral reflux, 21.7% had urinary tract infections, and 33.6% needed surgery (Bascietto et al., Prenatal Diagnosis, 2020). [2]
A first endoscopic procedure often works, but some children need more surgery. Among 24 fetuses with an antenatally detected ureterocele, 17 needed surgery after birth; every one began with cystoscopic incision, which was curative in 10 of 17 (58.8%), while 7 needed further operations (Turkyilmaz et al., Taiwanese Journal of Obstetrics & Gynecology, 2019). [3]
Key Takeaways
Feature | Details |
Medical Type | Congenital Urological Anomaly |
Prevalence | 1 in 5,000 to 1 in 12,000 children |
Most Common Type | Unilateral Extravesical (up to 75% of cases) |
Primary Symptoms | Often asymptomatic; UTI signs (burning, pain, fever) |
Main Complication | Vesicoureteral Reflux (VUR) and kidney damage |
Diagnosis Tools | Prenatal ultrasound, VCUG, Renal scan |
Core Treatment | Transurethral puncture or Ureteral reimplantation |
Prognosis | Excellent with early surgical intervention |
Understanding Ureteroceles
The urinary system relies on two ureters to transport urine from the kidneys to the bladder. In a healthy system, these tubes enter the bladder smoothly, allowing urine to drain without resistance. A ureterocele disrupts this process when the very end of the tube balloons out, creating a physical blockage at the bladder's entrance.
This condition is congenital, meaning it develops during pregnancy. It is considered a random occurrence and is not linked to any specific actions or environmental factors during fetal development. While it can affect one or both ureters, unilateral (one-sided) cases are far more frequent. [1]
Types and Classifications
Medical professionals categorize ureteroceles based on their location and extent:
Extravesical: The most common type (up to 75%), where the bulge extends toward the bladder neck and into the urethra. This is frequently seen in infants. [1]
Intravesical: A less common form (less than 25%) where the bulge remains entirely within the bladder. [1]
Unilateral vs. Bilateral: Most patients have only one affected ureter, though the condition can occur on both sides. [1]
Symptoms and Warning Signs
Many children with a ureterocele show no outward symptoms. Often, the first indication of a problem is the development of a Urinary Tract Infection (UTI) caused by stagnant urine.
Common UTI Indicators
Painful Urination: A burning sensation or crying during peeing in infants. [1]
Urinary Changes: Foul-smelling or cloudy urine, or the presence of blood (hematuria). [1]
Physical Signs: A palpable lump or pain in the abdominal area. [1]
Bladder Control: Frequent urination or an inability to fully empty the bladder. [1]
If a child experiences recurring UTIs, a healthcare provider will typically investigate for underlying structural issues like a ureterocele.
Complications of Untreated Ureterocele
The primary danger of a ureterocele is not the bulge itself, but the resulting backup of urine. When urine cannot exit the bladder, it may flow backward into the kidneys, a condition known as vesicoureteral reflux (VUR). [1]
Chronic backup and infection can lead to irreversible kidney damage. Unlike some other tissues, kidney damage does not heal, making early detection and treatment essential to preserving lifelong renal function. Other risks include the formation of kidney stones and chronic bladder dysfunction. [1]
Diagnosis and Testing
Advances in prenatal care mean that many ureteroceles are now caught before a child is even born.
Prenatal Ultrasound: Typically detected around the 20-week mark when a technician notices a swollen kidney or ureter.
Postnatal Confirmation: After birth, imaging tests like a Voiding Cystourethrogram (VCUG) or a renal scan are used to confirm the diagnosis and assess kidney function.
Adult Diagnosis: In rare cases, the condition may not be discovered until adulthood, often following a struggle with chronic kidney stones or infections. [1]
Management and Surgical Options
Treatment strategies are tailored to the patient's age, the severity of the blockage, and the presence of kidney damage.
Watchful Waiting
For adults or children whose ureteroceles are small and not causing infections or kidney stress, doctors may opt for "watchful waiting." This involves regular monitoring through ultrasounds to ensure the condition does not progress.
Surgical Interventions
For most symptomatic cases, surgery is the definitive solution:
Transurethral Puncture: A minimally invasive procedure where a surgeon uses a small camera (cystoscope) to enter the bladder and puncture the bulge, effectively "popping" the balloon to allow urine to flow. [1]
Ureteral Reimplantation: A more complex reconstructive surgery where the ureterocele is removed and the ureter is reattached to the bladder wall in a way that prevents future reflux. [1]
Upper Pole Nephrectomy: In cases where a portion of the kidney has already lost function due to the blockage, that specific section may be surgically removed. [1]
Early surgical intervention typically leads to an excellent prognosis, allowing children to lead normal, healthy lives with full kidney function. For more information on navigating pediatric health challenges, explore our infographic templates.
Frequently Asked Questions
Can a ureterocele be prevented?
No, it is a random developmental occurrence that happens during pregnancy and cannot be prevented.
Is a ureterocele the same as a kidney stone?
No, a ureterocele is a structural bulge in the ureter, though it can sometimes lead to the formation of kidney stones.
How common is this condition?
It affects approximately 1 in every 5,000 to 12,000 children.
Why is it more common in girls?
The exact reason is unknown, but the condition is significantly more prevalent in females than males.
Can adults be diagnosed with a ureterocele?
Yes, while it is usually caught in childhood, some adults are diagnosed after experiencing recurring UTIs or stones.
What is vesicoureteral reflux (VUR)?
It is a condition where urine flows backward from the bladder into the ureters and kidneys.
Does a ureterocele always require surgery?
Not always. If it isn't causing symptoms or kidney damage, a doctor may simply monitor it.
Is the surgery for ureterocele major?
It depends on the type. Transurethral puncture is minimally invasive, while reimplantation is a more significant reconstructive surgery.
Can a child live a normal life after surgery?
Yes, most children have an excellent outlook and no long-term restrictions once the blockage is repaired.
How is it caught during pregnancy?
It is usually seen as a swollen kidney or ureter during a routine 20-week anatomy ultrasound.
What is a "duplex kidney"?
It is a common variation where a person has two ureters for one kidney; ureteroceles are often associated with this.
Can a ureterocele cause permanent kidney damage?
Yes, if left untreated, the backup of urine can cause irreversible scarring and loss of kidney function.
What does "extravesical" mean?
It refers to a ureterocele that extends into the bladder neck or the urethra.
Is the condition hereditary?
While it happens during development, there is no strong evidence that it is passed down through families.
What is a VCUG test?
A voiding cystourethrogram is an X-ray test that shows how the bladder and ureters function while a patient is urinating.
Does a ureterocele cause pain?
Usually only if it leads to an infection or a kidney stone.
Can antibiotics cure a ureterocele?
No, antibiotics only treat the infections caused by the ureterocele; they do not fix the structural bulge.
How long is the recovery after surgery?
For minimally invasive punctures, recovery is very fast. Reconstructive surgery may require a few days in the hospital.
Can a ureterocele come back after surgery?
Recurrence is very rare after a successful surgical repair.
What is a renal scan?
It is a nuclear medicine test that shows how well each kidney is filtering and draining.
Can a ureterocele cause blood in the urine?
Yes, irritation or infection caused by the blockage can lead to hematuria.
What happens if only one kidney is affected?
The other kidney usually functions normally, but treatment is still needed to save the affected kidney.
Is general anesthesia used for the surgery?
Yes, most pediatric urological surgeries require general anesthesia to keep the child still and comfortable.
What are the signs of a UTI in a baby?
Fever, irritability, foul-smelling urine, and vomiting are common signs.
Can a ureterocele cause a lump in the belly?
In some cases, a very large ureterocele or a severely swollen kidney can be felt as a lump.
What is the success rate of reimplantation surgery?
It is very high, typically between 90% and 95%.
Does the condition affect both kidneys?
In most cases (unilateral), only one side is affected, but bilateral cases do occur.
Can a ureterocele cause incontinence?
Yes, if the bulge interferes with the bladder neck's ability to close properly.
What is "intravesical"?
It means the ureterocele is located entirely within the bladder.
Why is early diagnosis so important?
To prevent the backup of urine from causing permanent, irreversible damage to the kidneys.
Can a ureterocele be seen on a regular X-ray?
Usually not; specialized imaging like ultrasound or CT is required.
Does it affect the child's growth?
Not directly, but chronic kidney issues can sometimes impact overall health and development.
Are there different sizes of ureteroceles?
Yes, they can range from very small to large enough to fill a significant portion of the bladder.
What is a cystoscope?
A thin, flexible tube with a camera used to look inside the bladder.
Can a ureterocele cause high blood pressure?
Chronic kidney damage resulting from a ureterocele can sometimes lead to hypertension.
Is it a type of tumor?
No, it is a structural birth defect, not a cancerous or benign growth.
Can a ureterocele cause frequent urination?
Yes, by irritating the bladder lining or preventing full drainage.
What is the bladder neck?
The area where the bladder connects to the urethra to allow urine to exit the body.
Can a ureterocele cause back pain?
Yes, if urine backs up into the kidney (hydronephrosis), it can cause flank or back pain.
Is the condition more common in certain ethnicities?
There is no evidence that it affects any specific ethnic group more than others.
Can a ureterocele affect pregnancy later in life?
Usually not, provided kidney function was preserved and the bladder was successfully repaired.
What is hydronephrosis?
The swelling of a kidney due to a backup of urine.
Can a ureterocele cause a fever?
Only if it leads to a kidney or urinary tract infection.
Is the surgery done by a general surgeon?
No, it is typically performed by a pediatric urologist.
Can a ureterocele cause protein in the urine?
Chronic kidney stress or damage can sometimes result in proteinuria.
What is the "flap valve" in the bladder?
A natural mechanism that prevents urine from flowing backward from the bladder to the kidneys.
Can a ureterocele be diagnosed in an adult?
Yes, often during an investigation for chronic stones or unexplained UTIs.
Does the condition affect the ureters' length?
The ureters are the normal length, but the end is malformed.
Can a ureterocele cause crying during urination?
Yes, in infants, this is a common sign of the pain associated with a UTI.
What is the most important thing to monitor?
Kidney function and the absence of recurring infections are the top priorities.
Related Reading
Sources
Cleveland Clinic. Ureterocele: causes, symptoms, diagnosis & treatment. Cleveland Clinic. Last updated January 31, 2024. https://my.clevelandclinic.org/health/diseases/16322-ureterocele
Bascietto F, Khalil A, Rizzo G, et al. Prenatal imaging features and postnatal outcomes of isolated fetal duplex renal collecting system: a systematic review and meta-analysis. Prenatal Diagnosis. 2020;40(4):424-431. PMID 31834636. https://doi.org/10.1002/pd.5622
Turkyilmaz G, Cetin B, Sivrikoz T, et al. Antenatally detected ureterocele: associated anomalies and postnatal prognosis. Taiwanese Journal of Obstetrics & Gynecology. 2019;58(4):531-535. PMID 31307746. https://doi.org/10.1016/j.tjog.2019.05.018
Disclaimer
This article is for informational purposes only and does not constitute medical advice. Always consult with a qualified healthcare professional for diagnosis and treatment.
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