What is vesicoureteral reflux?
Vesicoureteral reflux (VUR) is the result of abnormal formation of the normal valve between the kidney and bladder. This valve ensures that urine travels one way from the kidney to the bladder. If your child has VUR, the urine does move backward into the ureters and kidney. Some children only have mild VUR, while others have large amounts of urine moving backward into their kidneys.
Although VUR by itself is not usually painful, VUR can become a problem if the child develops a urinary tract infection (UTI) in the bladder. With this type of infection, the bacteria are carried backward from the bladder to the kidneys, and this can result in serious infection and possibly damage to the kidneys.
Vesicoureteral Reflux (VUR) | Symptoms & Causes
What are the symptoms of vesicoureteral reflux?
Children who have vesicoureteral reflux may not feel sick, because VUR typically does not present symptoms. VUR is most often diagnosed after a child has experienced a UTI accompanied with a fever. Some children are also diagnosed shortly after birth if they had hydronephrosis (fluid in the kidneys) on their prenatal (before birth) ultrasounds.
Common symptoms of UTI in children include:
- pain or burning with urination
- strong or foul odor to the urine
- sudden onset of frequent urination or wetting incidents
- abdominal or flank pain (between the hip and rib)
What causes vesicoureteral reflux?
The cause of VUR is unknown, however there is a strong genetic component. Although no specific genes have been identified, VUR is common among children and siblings of parents with VUR. During infancy, VUR is more frequently in boys. In older children, VUR is more frequently diagnosed in girls.
VUR may also occur as a result of these less common issues:
- abnormal bladder function, due to nerve or spinal cord problems, such as spina bifida
- urinary-tract abnormalities, such as posterior urethral valves, bladder exstrophy, ureterocele, or ureter duplication
- dysfunctional voiding (bladder and bowel problems, including accidents, frequent urination, or constipation)
Vesicoureteral Reflux (VUR) | Diagnosis & Treatments
How is vesicoureteral reflux diagnosed?
Vesicoureteral reflux (VUR) can only be diagnosed by a test called a cystogram, in which a catheter is placed through the urethra into the bladder, and the bladder is filled with fluid. This procedure allows doctors to see the reverse flow of urine toward the kidney. There are two types of cystograms:
- voiding cystourethrogram (VCUG): an x-ray test that examines your child’s urinary tract. The bladder is filled with contrast using a catheter, and x-ray pictures are taken. The images show if there is any reverse flow of urine into the ureters and kidneys.
- radionuclide cystogram (RNC): this test is performed similarly to a VCUG with a catheter placed in the urethra and bladder, except a different fluid is used to highlight your child’s urinary tract.
A cystogram is most commonly done in a child who has had a UTI but may also be performed in infants who have hydronephrosis — a condition detected by ultrasound before birth.
There are other tests that are sometimes performed in children with VUR including:
- renal ultrasound
- DMSA renal scan
- blood tests
- urinalysis and urine culture
If a child is suspected of having a urinary tract infection, the urine needs to be sampled using special techniques to avoid contamination and false test results. For younger children and infants, this usually means passing a catheter into the bladder to obtain a urine sample. In some cases, a bag will be placed on the child to collect urine, although this method has a high rate of false results. In older, toilet-trained children, the child can urinate into a cup.
What are the treatment options for vesicoureteral reflux?
Based on the results of diagnostic vesicoureteral reflux testing, a physician will usually assign a number score for the VUR. Scores range from one to five or one to three, depending on the type of test performed. The higher the number or score, the more severe the VUR.
Children with mild VUR will likely improve over time and are less likely to need surgery. Once VUR resolves itself, it is important for parents to know that their child may still get UTIs.
If a child has more severe VUR or gets frequent kidney infections, despite preventative antibiotics, he or she may need surgery to correct the VUR. The severe form of VUR is less likely to resolve on its own.
Ureteral reimplantation surgery
Ureteral reimplantation surgery is a surgical procedure where the connection between the ureter and the bladder is reconstructed to prevent VUR.
Endoscopic treatment is an option for some children who have lower grades of VUR. The procedure is performed on an outpatient basis under general anesthesia.
The doctor inserts a small telescope into the bladder through the urethra (the tube connects the bladder to the outside) and injects a small amount of gel-like material under the opening of the ureter. The injected material partially closes the opening and prevents the urine from going backward toward the kidney.
The success rate of this procedure is about 75 percent, and there are very few complications. However, we do not know how long the results will last, since some children can have recurrence of their VUR months or years later. Although there are some advantages to endoscopic treatment, it is not always the best option.
Robotic surgical treatment
Robot-assisted laparoscopic surgery is performed by inserting small instruments through several tiny incisions in the abdomen. This procedure is normally performed in patients who require repeat surgery for VUR or to treat VUR in adolescents and young adults. The approach is rarely performed in younger children because the success rate for open surgery is better (about 98 percent) and with few complications.
Continued technical improvements in robotic surgical treatment will likely provide good alternatives to open surgery in the future. We have made great progress with robotic-assisted laparoscopic surgery for VUR.
How we care for vesicoureteral reflux
The Boston Children’s Hospital Department of Urology team takes a conservative approach to VUR. Most children will outgrow their VUR on their own, and we give them a chance to do just that.
Our main goal is to treat vesicoureteral reflux and prevent infections that might affect the kidneys and possibly cause kidney damage. Our specialists provide a comprehensive approach to the management of vesicoureteral reflux from initial diagnosis to treatment and follow-up care.
Vesicoureteral Reflux (VUR) | Frequently Asked Questions
VUR is a condition that affects about 1 to 3 percent of all children. However, there are certain groups of children in whom VUR is much more common, including:
- children who have hydronephrosis, or excessive fluid in the kidneys. Among this group, VUR is seen in about 15 percent of these children when testing is done after the baby is born.
- children who have a urinary tract infection, particularly if the infection was associated with a fever. Among this group, VUR is found in 50 to 70 percent of these children.
No. However, the urinary tract infections that are often associated with VUR can be prevented with changes to toileting behaviors, management of constipation, and preventive antibiotics.
Yes, VUR is more common in family members of people with VUR. For this reason, you should discuss with your doctor whether siblings or other family members should be tested for VUR.
We usually see patients with VUR every six to 12 months. Infants may be seen more often. For children with persistent VUR, we recommend VUR testing every year to two years, depending on the child's age.
The most important issue for children with VUR is a urinary tract infection. Kidney infections can cause kidney damage, so parents need to watch for signs of UTI. In young children, this usually means a fever. Other signs of UTI include foul-smelling urine, pain with urination, blood in the urine, increased frequency of urination or wetting accidents, or flank and abdominal pain.
Many children with VUR will outgrow the condition on their own. Therefore, we do not perform surgery as initial treatment in most children. Some children, however, will require surgery to correct VUR. The most common reasons for proceeding with surgical correction of VUR are repeated UTI with kidney involvement, failure of VUR to resolve on its own over time, or severe VUR that is very unlikely to resolve.
During the open ureteral reimplantation, the surgeon makes an incision in the lower abdomen and exposes the bladder. The junction of the bladder and the ureter (the tube connecting the bladder to the kidney) is reconstructed to prevent urine from flowing backward up into the kidney. A catheter is left in the bladder to drain the urine for the first one to two days after surgery.
Yes. The preventive antibiotics used are given once a day and are very low dose. There are some risks associated with any medication, but we believe that the benefits of preventing UTI (and kidney scarring) in children with VUR outweigh any small risks associated with taking the antibiotics for long periods. We have treated thousands of children with preventive antibiotics for many years with very few severe side effects.
Children do not become “immune” to antibiotics. Their immune systems (the germ-fighting and infection-fighting systems) remain fully functional and aren’t altered by being on these medications. Children can still fight off infections normally. However, the bacteria (germs) living on and inside of human beings can become resistant to certain antibiotics through chronic or ongoing exposure.
This problem is minimized by properly selecting the best antibiotic medicines for UTI prevention, using a very low dose, and giving it only once a day. Resistance to antibiotics is a major concern in health care and is being studied carefully.
Your doctor often will use ultrasound to follow your child’s kidney growth and health. We perform special tests to check for VUR every one to two years. In some cases, VUR can result in scarring in the kidney, which can lead to high blood pressure. Children with scars in their kidneys should have their blood pressure and urine checked every six months, even if their VUR has gone away.
Vesicoureteral Reflux (VUR) | Research & Clinical Trials
In addition to leading the way in the use of robotic surgery, Boston Children’s Hospital is continually working toward faster, more accurate diagnoses and more effective treatments for children with urologic disorders. Among the recent areas of research that our Department of Urology has conducted, several hold great promise for improving the lives of children with vesicoureteral reflux.
Managing pain and discomfort from vesicoureteral reflux surgery
Boston 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 for VUR.
Thanks to 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 the development of less-invasive methods of correcting VUR. Our pioneering surgeons have used robotic-assisted laparoscopic surgery to successfully correct VUR. We also use endoscopic techniques to perform injections to correct VUR in many children.
Determining the role of genetics in VUR
A Boston Children's study of VUR genetics is looking at families who have multiple members with VUR. This will help us learn about VUR genetics to determine how it is inherited, as well as identify which genetic factors put children at risk for recurrent UTIs or kidney scarring.