When a baby is born with a blockage in the area where the ureters meet the bladder, the diagnosis is ureterovesical junction obstruction (UVJ), also known as a megaureter. This congenital condition is usually diagnosed during pregnancy by a prenatal ultrasound that shows swelling of the kidneys (hydronephrosis) and the ureter (hydroureter)—the tubes that drain urine from the kidneys into the bladder. If we detect this problem in your unborn baby, we begin to monitor your baby regularly during pregnancy and immediately after birth.
With this condition, the reason for concern is that a swollen ureter can block urine from flowing normally and/or cause urine to back up in the urinary tract system. Both effects can damage the kidneys, but early diagnosis and treatment can prevent such an outcome. It is also possible for swelling to exist without causing any drainage problems. UVJ is two to four times more likely to happen in boys than girls and it usually occurs only on the left side of the body.
Eighty-five to 90 percent of children born with UVJ obstruction outgrow their condition without treatment by the time they are ready for potty training. This is why we sometimes take a wait-and-see approach with a newborn who is diagnosed with UVJ. During this waiting time, many children are placed on a daily antibiotic to prevent infection in the kidney until the dilation improves. We continue to monitor them closely until the problem resolves on its own or begins to have a serious effect on kidney function.
Although most UVJ obstructions occur while babies develop in their mother’s womb, it occasionally presents in older children with a kidney stone or infection. Their symptoms include urinary tract infection, nausea, vomiting, fever, bloody urine, kidney stones and side pain.
Diagnosis of Ureterovesical Junction Obstruction
Once a baby is born, we fully assess the anatomy and the severity of the condition by running tests. Among them are:
- Blood tests. Your child's doctor will perform a blood test to measure kidney function and see how well infants excrete creatinine—a waste product that results from the kidneys doing their work.
- Voiding cystourethrogram (VCUG). In this test, contrast dye is injected into a bladder catheter and allows the doctor to see any vesicoureteral reflux—the amount of urine that backs up into the kidneys. This test confirms the cause of the obstruction.
- Mercaptoacetyltriglycine (MAG3) renal scan. This diagnostic nuclear medicine test allows the doctor to see his/her kidneys and learn more about how they are functioning.
- Renal scan. This is a nuclear scan to check kidney function and the ability of the kidneys to drain.
Once one or more of these tests are done, we can plan treatments for any obstructions, if necessary.
If swelling in the kidneys and ureter(s) does not subside or the kidneys begin to falter, surgery may be necessary to prevent lasting damage. The permanent surgery to repair UVJ—ureteral reimplantation—removes the damaged section of the ureter(s) and reattaches the tapered, healthy portion to the bladder. This procedure can be done using minimally-invasive, endoscopic or robotic-assisted techniques. The method recommended for your child depends on several factors, such as his/her size, anatomy and individual conditions.
Sometimes, an interim surgery is necessary because the bladder is not large enough to handle ureteral reimplantation. In these cases, pediatric urologists at Riley at IU Health may suggest one of two temporary procedures:
- Ureterostomy. A temporary procedure that disconnects the ureter from the bladder and brings the ureter out to the skin where urine can drain into a baby’s diaper.
- Refluxing ureteral reimplantation. A temporary procedure that improves drainage of the affected kidney. This novel technique was founded and perfected by physicians at Riley at IU Health and simply plugs the blocked ureter back into the bladder to cure the blockage but allowing reflux (urine backing up into kidney).
Both temporary surgeries are designed to give infants extra time to grow. Once a child is mature enough—usually between 18 months and two years of age—surgeons can reimplant the ureter in non-obstructed and non-refluxing way thus to permanently reconnect the healthy portion of ureter to the bladder.
If your child is diagnosed and treated for UVJ at Riley at IU Health, we will follow them through the first years of life to make certain they have no further issues with continence or kidney function. Most children recover from surgery quickly and have few, if any, issues afterwards. These patients will be followed with renal bladder ultrasounds regularly and typically have a greater than 90% success rate.
Key Points to Remember
Key Points to Remember
- An obstruction that occurs in the area where the ureters meet the bladder is called a ureterovesical junction obstruction (UVJ).
- UVJ is usually found during fetal development and is more common in boys than girls.
- Older children can develop UVJ as a result of kidney stones or infection
- Most children born with UVJ outgrow their condition and do not require treatment.
- If kidney function is compromised or the urinary system is threatened with damage due to UVJ, pediatric surgeons can repair the blockage by removing the obstruction in the ureter and reattaching the ureter to the bladder.
- Some children require a temporary surgery before their UVJ can be permanently repaired because their anatomy is not developed enough.