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What is a ureterocele?

At Boston Children’s Hospital, we understand that if your infant or child has been diagnosed with a ureterocele, you and your family are under stress. So we’ll approach your child’s treatment with sensitivity and support — for your child and your whole family.

Here are some of the basics about ureteroceles:

  • If the end of your child’s ureter (a tube that carries urine from the kidney to the bladder) does not develop properly, it can bulge, forming a small pouch that can block the flow of urine. That bulge or pouch is called a ureterocele.
  • Ureteroceles are birth defects that occur in approximately 1 out of every 2,000 babies. They occur most often in Caucasians.
  • A ureterocele is 10 times more common in girls than in boys, because a duplex collecting system (two ureters for one kidney) is more common in girls.
  • In some children with a ureterocele there may also be backward flow of urine into the kidney, which can damage the kidney (a problem called vesicoureteral reflux).
    • Large ureteroceles may also protrude into the urethra and obstruct the flow of urine out of the bladder.
  • A ureterocele is most often diagnosed in children younger than two years of age with an ultrasound or a voiding cystourethrogram (VCUG). In many cases, the ureterocele or its effects are observed on ultrasounds before birth.
  • Surgery is sometimes necessary to repair your child’s ureterocele, but if the blockage is not severe, your child’s doctor may choose to simply observe her for a while to make sure the condition doesn’t get worse.
  • Small ureteroceles may not require any treatment at all.

How Boston Children’s Hospital approaches ureteroceles

One benefit to being at Children’s is the presence of our excellent Maternal Fetal Care Center. If your baby is diagnosed prenatally with a ureterocele, our multidisciplinary team will follow his condition closely from gestation through birth and beyond.

Should your child’s doctor deem that she needs surgery, Children's is home to the largest pediatric Department of Urology in the world, with physicians who are experts in a wide range of proven procedures. We perform more than 2,600 surgical procedures each year and care for almost 15,000 children from throughout the country and all over the world. Your child’s doctor will work with you to design a customized plan of treatment that fits your child and her condition.

Reviewed by: Caleb P. Nelson, MD, MPH. © Children’s Hospital Boston; posted in 2012.

Ureterocele | Symptoms & Causes

What is a ureterocele?

A ureterocele is a small pouch or swelling at the end of your child’s ureter. Normally, the urine flows freely from the kidney to the bladder, but a ureterocele can block part or all of the stream, sometimes even causing the urine to flow backward into your child’s kidney. How much the urinary flow is affected and whether the kidney is at risk of being damaged will indicate how severe your child’s condition is.

Are all ureteroceles the same?

No. Ureteroceles vary widely in terms of severity and location. Some ureteroceles can be virtually nonexistent while others can take up the entire bladder. The severity of a ureterocele depends on its size and the subsequent degree of obstruction it causes.

  • Mild: A small ureterocele (the most common type) will only minimally affect the flow of urine between your child’s kidney and bladder. Her doctor may choose to simply continue to observe her to make sure the condition doesn’t worsen.
  • Severe: A larger ureterocele can lead to more severe blockage of the flow of urine. This can cause problems such as urinary tract infections, vesicoureteral reflux and even kidney damage.

What causes ureteroceles?

The exact reason why a child develops a ureterocele is not known. This congenital (existing at birth; not acquired) condition is often discovered during a routine prenatal ultrasound, which indicates that they arise from problems in the development of your child’s urinary tract and how the ureter inserts into the bladder.

The condition does run in families, so researchers assume there is a genetic component, but specific genes have not been isolated.

Signs and symptoms


Small ureteroceles only minimally obstruct the flow of urine, so most children with ureteroceles won’t have any symptoms.


Larger ureteroceles can cause a variety of symptoms; by far the most common is a urinary tract infection (UTI).

Common symptoms of UTI in children include:

  • fever
  • pain or burning with urination
  • strong or foul odor to the urine
  • sudden onset of frequent urination
  • enuresis (wetting during the day and night)

A large ureterocele can also cause one or more of the following symptoms in your child:

  • a bulge in the abdomen area (if the ureterocele is obstructing urine from leaving the bladder)
  • incontinence
  • blood in the urine
  • failure to thrive
  • abdominal pain
  • pelvic pain
  • difficulty urinating
  • recurrent UTIs

Are there any other complications?

This can put your child at risk for the following complications:

  • vesicoureteral reflux (VUR) — a condition in which the urine flows from the bladder back up toward the kidneys. VUR can predispose a child to developing kidney infections and kidney damage.
  • hydronephrosis — a condition in which the backup of urine causes the kidney to swell.
  • less commonly, a ureterocele may contribute to the formation of kidney stones.

If left untreated or misdiagnosed, a large ureterocele can damage your child’s kidneys and urinary system. Chronic reflux of urine into the kidney, infection and obstruction can result in irreversible kidney damage that may require a surgical removal of a piece of the kidney called a nephrectomy.

  • That’s why it’s vital to see a specialist in urology for an accurate, timely diagnosis.

What is the long-term outlook for my child?

If your child has a large ureterocele that puts her kidney at risk, it may be necessary to perform surgery to avoid permanent kidney damage. But even the most severe ones can be effectively treated if detected early. With an accurate diagnosis, appropriate treatment and conscientious management, your child should go on to achieve normal urinary function.

Ureterocele | Diagnosis & Treatments

How is a ureterocele diagnosed?

Ultrasound: since a ureterocele is a congenital (present at birth) condition, it is often detected before birth when a prenatal ultrasound shows hydronephrosis (swelling) of a kidney. In some cases, the hydronephrosis is detected prenatally, but the ureterocele is not found until more thorough tests are completed after the baby is born.

If it’s not found then, it may not be discovered until your child has recurrent urinary tract infections.

If we’ve noted a ureterocele (or hydronephrosis) in a prenatal ultrasound, your doctor will typically perform the following tests a few weeks after your baby is born to diagnose the condition and assess the function of your child’s urinary system:

  • Renal ultrasound (RUS): This ultrasound focuses specifically on the kidneys and bladder to give doctors a general idea of how severe the hydronephrosis is. If a ureterocele is present, it can also be identified through this imaging.

  • Voiding cystourethrogram (VCUG): This special kind of x-ray is used to examine the anatomy of your child’s bladder and check for reflux. Using a small tube called a catheter, doctors will fill your child’s bladder with a liquid containing iodine. As the bladder fills and your child urinates, the flow of the liquid will be visible on video x-ray images.

  • Renal scan (DMSA or MAG 3): This is a type of nuclear scanning test that helps measure the difference in function between the two kidneys and also estimate the degree of blockage in the urinary system. After a tiny amount of radioactive material (radioisotope) is injected into your child’s bloodstream, a special camera called a gamma camera is used to take pictures of the kidneys as the radioactive material moves through them, showing how well they are filtering and draining.

  • Blood tests: These let the doctor see how well your child’s kidneys are working.

  • Urinalysis and urine culture: Laboratory tests that examine the urine. These tests can indicate microscopic blood or protein in the urine, other chemicals, or evidence of a UTI.

Older children who come to us with some or all of the symptoms of a ureterocele are diagnosed using the same method.

After we complete all necessary tests, our experts meet to review and discuss what they have learned about your child's condition. Then we will meet with you and your family to discuss the results and outline the best treatment options for your child.

If your child has been diagnosed with a ureterocele, the doctors and care team at Boston Children's Hospital understand you may be worried. We specialize in family-centered care, which means that from your first visit, you¹ll work with a team of professionals who are committed to supporting all of your family's physical and psychosocial needs.

What are the treatment options for ureteroceles?

Treatment for ureteroceles depend on when they're diagnosed and how severe your child's symptoms are.

If a ureterocele has been diagnosed prenatally:

If a routine prenatal ultrasound has shown the presence of a ureterocele, your child's doctor will recommend a sequence of imaging tests after you child is born to investigate the anatomy of the urinary tract and the function of your child's kidney.

Based on how large the ureterocele is and how it is affecting the kidney, your doctor will either continue to observe the condition or begin treatment:

  • continued observation is the most common result. You'll set up a follow-up appointment for another set of imaging studies in a few months.
  • a course of daily preventive antibiotics (to combat urinary tract infections) — In this case, your child would also return in several months for another set of imaging studies.
  • surgery to remove the ureterocele — In rare and severe cases, your child's doctor may recommend a surgical procedure early in infancy to drain the ureter and remove a large ureterocele that is putting your child at risk for significant kidney damage.
  • If your child's kidney has already been damaged, the surgeon may also remove the part of the organ that is no longer functioning in an operation called a nephrectomy.
  • In other cases, the ureterocele may be removed and the ureters reattached to the bladder to allow normal flow of urine, and prevent reflux.

How often will my baby need to be seen?

Infants may be seen every 3-4 months. A series of imaging studies gives us a sense of the size and severity of the ureterocele. If we're reassured that it's not causing any harm to your child's kidneys, we'll begin to spread the visits out to every 6-12 months depending on age.

Older children

If a ureterocele has not been diagnosed prenatally, you might not know about it until your child has recurrent urinary tract infections or becomes sick as a result of an obstructed urinary system.

If that's the case for your child, your doctor may prescribe antibiotics. If they don't start helping quickly, we may admit your child to the hospital and administer more antibiotics and IV fluids. In severe cases, we'll drain the ureter to stabilize your child, and then perform the imaging studies mentioned above to assess her condition and decide how to proceed with observation or treatment.

Are antibiotics safe to take for long time?

Yes. The low-dose, preventive antibiotics are given once a day and have helped thousands of children for many years with very few severe side effects. There are some risks associated with any medication, but we believe that the benefits of preventing UTI (and kidney scarring) in children with more severe ureteroceles outweigh any small risks from taking the antibiotics for long periods.

Don't children become “immune” to the antibiotics?

Children do not become immune to antibiotics. Their immune systems remain fully functional and aren't changed by being on these medications. However, the bacteria that live on and inside of human beings can become resistant to certain antibiotics through prolonged exposure. Since most UTIs are caused by the germs that live on us, this can be a problem.

My child needs surgery. What do we do next?

Should your child's doctor deem that he need surgery, Children's surgeons have vast experience in both traditional open and minimally invasive robotic-assisted surgical procedures. You'll meet with your child's doctor and work together to design a customized plan of treatment that fits your child and the condition.

Is there anything we need to do to prepare for the surgery?

Your child's doctor will give you a packet of information about what to do and not do in the days leading up to your child's surgery. These instructions include how long before the surgery your child should refrain from eating and drinking, when you should arrive at the pre-op clinic, what you should bring and how long you should expect to remain in the hospital.

What are the different options for surgical procedures?

Open surgery

If your child's doctor decides that your child should have a traditional open procedure, the incision will be larger and your child will stay in the hospital for one or two more days, but the results will be very similar.

Endoscopic surgery

In certain cases, the procedure can be performed through a small telescope inserted through your child's urethra, and no incision is needed. As you might expect this procedure has a rapid recovery, but not all children will be helped by the endoscopic technique.

Robotic surgery

At Boston Children's Hospital, we can perform state-of-the-art laparoscopic and robotic surgery.

  • Your child's surgeon will insert instruments into his abdomen through small punctures, which are then used under the guidance of a small camera, also inserted through an incision.

Which method is better?

The choice of surgical approach is highly individual and depends very much on the details of a child's condition. Traditional open surgery is a time-tested method of correcting a ureterocele with very few complications. Laparoscopic surgery reduces the size of the incision, and may reduce the amount of pain and the time your child will need to stay in the hospital. Your doctor will discuss with you which option is better for your child.

How might a ureterocele affect my child's long-term health?

If your child has a large ureterocele that could cause damage to her kidney, surgery may be necessary. But even large ureteroceles can typically be effectively treated – and your child should go on to achieve normal urinary function.

What makes your approach unique?

A ureterocele is a pediatric condition, so it's important that your child be seen at a dedicated pediatric hospital. The specialists in the Department of Urology at Children's have years of experience managing this sometimes subtle and rare condition.

Can ureteroceles be prevented?

No. Ureteroceles are congenital conditions. However, the urinary tract infections that are often associated with ureteroceles may be prevented with antibiotics.

Coping and support

We understand that you may be worried about your child's ureterocele. But there are lots of resources available for your whole family—within Children's, in the outside community and online.

Children's resources for families:

Maternal Fetal Care Center: The MFCC at Children's is set up to offer diagnosis and ongoing care for a mother carrying a baby with a confirmed or suspected congenital anomaly.

Patient to patient: Want to talk with someone else whose child has been treated for a ureterocele? We can put you in touch with other patients who have been through similar experiences and can share their stories.

On our For Patients and Families site, you can read all you need to know about:

  • getting to Children's
  • accommodations
  • navigating the hospital experience
  • resources that are available for your family

Ureterocele | Research & Clinical Trials

At Boston Children’s Hospital, we’re continually learning from our experiences with patients, evaluating the most current data and studying the causes of diseases and new treatments with the aim of developing innovative methods for caring for kids with congenital conditions like ureteroceles.

Proteomics and biomarkers

  • Proteomics, the study of an organism's complete complement of proteins, picks up where the Human Genome Project left off, asking what proteins each gene codes for and what they do in the body.

  • In urology, Richard Lee, MD, and colleagues are using proteomics tools to categorize the entire collection of urine proteins and understand how the "urine proteome" changes in congenital urologic conditions like ureteroceles. They are also using proteomics to detect changes in bladder tissue that may be associated with disease progression.

Managing pain after surgery

  • Children’s has been a pioneer in anesthesia for children, and our urologists and anesthesia doctors have worked together to develop highly effective pain-management techniques for children who have surgery.

  • Using these methods, most children recover quickly after surgery and their pain is kept to a minimum. Most children can go home within one or two days. In addition, we have been leaders in development of less invasive methods of correcting ureteroceles. Our pioneering surgeons have used laparoscopic and robotic-assisted laparoscopic surgery to successfully correct ureteroceles in many children.

  • Hiep T. Nguyen, MD, Co-Director, Robotic Surgery, Research and Training Program at Children’s has undertaken a series of studies to that suggest that giving children a pre-operative aerosol-based pain medication can lead to a reduction in post-operative pain. Dr. Nguyen studied a set of children undergoing robotically assisted procedures to remove urinary tract blockages.

Working together to treat ureteroceles

Launched hospital-wide in 2011, the SCAMPs (Standardized Clinical Assessment and Management Plans) initiative aims to streamline and standardize care for conditions like ureteroceles. Combining years of research on clinical outcomes, the accumulated body of knowledge allows physicians to customize care for each child while using a tried-and-tested framework that’s been effective in treating other children with the same condition.

Ureterocele | Programs & Services