Vesicoureteral Reflux (VUR)

    Last updated date: 03-Mar-2023

    Originally Written in English

    Vesicoureteral Reflux (VUR)

    Vesicoureteral Reflux


    Urine normally passes down from the kidneys to the bladder via tubes called ureters. Urine flows backward from the bladder up the ureter to the kidney in vesicoureteral reflux. It can occur in one or both ureters. Bacteria from the bladder can enter the kidney if the "flap valve" fails and allows urine to flow backward. This may result in a kidney infection, which can lead to kidney damage.

    The ureters and kidneys get big and twisted as the flow of urine back up the ureters becomes more acute. If there is an infection, more severe reflux is associated with an increased risk of kidney injury.


    What is Vesicoureteral reflux?

    Vesicoureteral reflux definition

    The abnormal leakage of urine from the bladder into the ureter and up to the kidney is known as vesicoureteral reflux. Most of the time, this is a condition that a child is born with. It is caused by an improper ureter-bladder connection. As a result, the bladder's muscular backing does not completely cover the ureter, allowing urine to overflow into the kidney. The degree of urine backflow is rated on a scale from I to V.

    Because the ureter's passage into the bladder expands and lengthens as the kid grows, the reflux may reduce or eliminate. The lower the grade of reflux, the more probable it is to resolve spontaneously. During infancy, guys are more likely to have vesicoureteral reflux. Girls are more likely to be diagnosed with vesicoureteral reflux in older children.

    Vesicoureteral reflux can also develop in children who have aberrant bladder function as a result of nerve or spinal cord issues such spina bifida. Children who have bladder and bowel problems may be predisposed to vesicoureteral reflux. Other urinary system anomalies, such as posterior urethral valves, ureterocele, ureteral duplication, or bladder exstrophy, can cause vesicoureteral reflux in children.


    Who is more likely to have vesicoureteral reflux?

    VUR affects around one in every three children who have a UTI and a fever.1 Because some children with VUR who do not have symptoms or issues are not evaluated, the number of children with VUR may be larger.

    The younger a child is, the more probable he or she is to develop VUR. VUR is more frequent in babies and children under the age of two, although it may also be found in older children and adults.

    VUR is more common in children who have faulty kidneys or urinary systems. VUR is more common in girls than in boys. If a child's sibling, sister, or parent has VUR, the youngster is more likely to get it as well. One in every four siblings of a kid with VUR will also have the disorder. A bit more than one in every three children with a VUR parent will also have the disorder.


    What causes vesicoureteral reflux?

    vesicoureteral reflux causes

    The ureters enter the urine bladder obliquely and run submucosally for some distance in healthy people. This, together with the ureter's muscular attachments, aids in the ureter's posterior security and support. These characteristics work together to provide a valve-like function that closes the ureteric opening during urine storage and voiding. Failure of this process occurs in VUR patients, resulting in backward (retrograde) urine flow.

    • Primary VUR
      The valvular mechanism is insufficient because the ureter's submucosal length is insufficient relative to its diameter. This is caused by a congenital deficiency or a lack of longitudinal muscle of the ureter within the bladder, resulting in a ureterovesicular junction (UVJ) anomaly.

    • Secondary VUR
      Secondary VUR in children can occur for a variety of causes, including a blockage or constriction in the bladder neck or urethra. A tissue fold, for example, may obstruct the urethra. Because the obstruction prevents some pee from exiting the body, urine flows back up the urinary system.

      Secondary VUR can occur in children if the nerves to the bladder do not function properly. Nerve disorders can make it difficult for the bladder to relax and contract appropriately in order to discharge pee.

      Secondary VUR in children frequently causes bilateral reflux, which means that the VUR affects both ureters and both kidneys. A urinary obstruction in a fetus in the womb can occasionally be diagnosed by doctors. 

    • Anatomical
      urethral or meatal stenosis; posterior urethral valves When feasible, these reasons are handled surgically.

    • Functional
      Instability of the bladder, neurogenic bladder, and non-neurogenic bladder Because of the increased pressures associated with inflammation, bladder infections can induce reflux. If the underlying reason is treated and resolved, functional VUR will typically resolve. Medical and/or surgical intervention may be required.


    How is VUR graded?

    VUR grade

    The pictures obtained on a VCUG are used to grade VUR. The lower the degree of reflux, the more likely it will resolve without surgery. It is possible to have VUR bilaterally (on both sides) with varying grades.

    • Grade 1: This is the most moderate kind of VUR. Urine runs up into the ureter but not into the kidney, and the ureters seem normal in size.
    • Grade 2: Pee ascends the ureter and reaches the area of the kidney where urine is collected before discharging (renal pelvis). The ureter is of normal size.
    • Grade 3: Similar to grade 2 expect that the ureters and/or the renal pelvis look more full.
    • Grade 4: Similar to grade 3, only the ureter is greatly swollen and the kidney calyces are blunted.
    • Grade 5: The most severe kind of VUR. The ureter is quite large and convoluted, similar to grade 4. (full of twists).


    What are the symptoms of vesicoureteral reflux?

    Symptoms of vesicoureteral reflux

    VUR does not have any distinct symptoms. However, in children, frequent and recurring urinary tract infections with fevers (called febrile UTIs) may be an indication of VUR. In fact, over one-third of children with febrile UTIs develop VUR. However, it is critical to recognize that reflux does not cause urinary tract infections and that urinary tract infections do not cause reflux. Urinary tract infections can cause the following symptoms:

    • Foul smelling or cloudy urine
    • Fever
    • Stomach ache
    • Backache
    • Side pain
    • Burning or pain while urinating
    • Frequent and urgent urination
    • Headache
    • Vomiting


    How is vesicoureteral reflux diagnosed?

    vesicoureteral reflux diagnosis

    To diagnose the grade of VUR, doctors use imaging tests.

    Imaging tests

    Before you and your kid's doctor decide to employ urinary tract imaging to diagnose VUR in your child, a doctor takes the child's medical history into account.

    • Age
    • Symptoms
    • Family history of VUR
    • Sexual activity level in an older child

    Doctors use the following imaging tests, or tests to see organs inside the body, to help diagnose VUR

    • Abdominal ultrasound: An ultrasound utilizes sound waves to see into your child's body without using x-ray radiation. An abdominal ultrasound, sometimes known as a transvaginal ultrasound, may produce pictures of the whole urinary system, including the kidneys and bladder. An ultrasound can reveal whether or not a child's kidneys or ureters are dilated or enlarged. Your youngster will lay on a comfortable table throughout this painless examination. A technician glides a wand known as a transducer softly over your child's belly and back.

    • Voiding cystourethrogram (VCUG). This enables direct visualization of a refluxing ureter. A VCUG is a type of X-ray that looks at the urinary system. A catheter (a hollow tube that drains urine from the bladder to the outside of the body) is inserted into the urethra, and the bladder is filled with a liquid dye. As the bladder fills and empties, X-ray pictures are collected. The photos illustrate whether or not urine is flowing backward into the ureters and/or kidneys. VCUGs are a frequent procedure, although many children and parents dislike the catheter. A numbing gel is sometimes used to alleviate pain. Talking to your youngster ahead of time about what to expect will help alleviate anxiety. Furthermore, the more comfortable the youngster is during the process, the less pain they will experience.

    An ultrasound is frequently used as the first imaging test to look for renal issues caused by VUR.


    Lab tests

    To check for a UTI, health care practitioners frequently do urine analysis on a urine sample. A UTI can be detected by white blood cells and bacteria in the urine. To confirm a UTI, a urine culture is required.


    VUR and Infections

    VUR and Infections

    VUR is most commonly discovered after a kid gets a UTI. A bacterial infection of the urinary system is known as a urinary tract infection. It might affect the kidney, the bladder, or both. In fact, about one in every three children with a UTI has vesicoureteral reflux.

    Some signs of a kidney infection are:

    • Fever
    • Pain in the belly or lower back
    • Feeling ill in general
    • Feeling sick to the stomach
    • Throwing up

    Signs of a bladder infection are:

    • Painful and frequent voiding
    • An urgent need to pass urine
    • Wetting (lack of urinary control)

    The signs of UTIs in babies may not be as clear, but may involve:

    • Fever
    • Fussiness
    • Throwing up
    • Diarrhea
    • Poor weight gain

    UTIs can occur in older children as well, with no obvious symptoms. The germs that cause UTIs are frequently found in a child's excrement. Even with good hygiene, germs can accumulate in the groin and reach the urethra and bladder. If the child has VUR, the bacteria might go to the kidney(s) and cause infection.

    Though VUR is most commonly discovered after a kid has been treated for a UTI, it is important to understand that VUR does not cause UTI, and UTI does not induce reflux.


    How is vesicoureteral reflux treated?

    vesicoureteral reflux treate

    The course of treatment depends on:

    • The child’s age, overall health and medical history.
    • The extent of the condition.
    • The child’s tolerance for specific medications, procedures or therapies.
    • Expectations for the course of the condition.
    • The family’s preferences.

    Our professionals may use a grade system (ranging from 1 to 5) to identify the child's level. The more severe the reflux, the higher the grade.

    Many cases of reflux, particularly those of lower degree, can be resolved with time, generally within five years. To help keep their pee sterile and free of bacteria, most youngsters will be prescribed prophylactic antibiotics until they are potty trained. While we wait for the VUR to go away on its own, we can safeguard the kid against urinary tract infections with this therapy option. Some parents are concerned about long-term antibiotic prophylactic use owing to the danger of antibiotic resistance – a condition in which bacteria grow resistant to low-dose antibiotics over time, rendering the medications ineffective on the kid. Antibiotics have little influence on antibiotic resistance when used correctly.

    When children are potty trained, we work with them and their families to ensure that they are implementing the optimal behavioral adjustments to lower their risk of infection. As children develop, their kidneys are checked with periodic ultrasounds to ensure there is no damage. The VCUG is not conducted on a regular basis, although it is frequently repeated when a kid reaches school age or if problems such as breakthrough infections or recurrent febrile UTIs continue.

    A breakthrough infection happens when an illness arises when a youngster is on preventative antibiotics. If a kid continues to have recurrent febrile UTIs or breakthrough infections when on prophylaxis, they may require surgical surgery to correct their reflux. A cystoscopy and Deflux injection are the most typical procedures performed. Deflux is a gel that is injected into the refluxing ureter and is constructed of two sugar-based ingredients. The treatment is non-invasive and does not necessitate an incision.

    Some children will not be suitable candidates for Deflux, or the procedure may fail. If this occurs, we can perform ureteral reimplant surgery at our facilities. The ureter is removed where it connects to the bladder and reimplanted at a different location on the bladder during this procedure. It is approximately 99 percent effective at resolving reflux. Following any surgical intervention, a VCUG and ultrasound are performed to determine whether the VUR has resolved.



    Prognosis of Vesicoureteral Reflux

    When the incidence of VUR is compared to that of end-stage renal disease caused by VUR, it is clear that the result for most children with VUR is favorable. Assume that VUR affects more children than the presently estimated 1% to 2%: for example, if VUR affects 3% of children, or 30,000 per million children, only 1 in 6000 children (or 5 per million children) will acquire end-stage renal disease. End-stage kidney failure is infrequent, especially when caused by reflux nephropathy, whereas VUR is a rather common anomaly.

    Reflux nephropathy is indicated as the major cause in around 5% to 7% of persons undergoing end-stage renal failure programs. This is a clinical diagnosis based on a history of renal tract imaging findings rather than a biopsy diagnosis. Other factors must be present on the causative route for significant kidney damage to result in renal failure. UTI is commonly blamed for producing kidney damage and transforming a refluxing normal kidney into a highly damaged one that eventually fails.

    This also appears implausible considering that UTI is a frequent disease, affecting around 6% of all children, because cohort studies show that damage existed prior to UTI and few new abnormalities emerge after UTI. These findings indicate that the essential event in the pathogenesis of severe renal parenchymal abnormalities associated with VUR occurs antenatally as part of the reflux-congenital renal hypoplasia/dysplasia syndrome. VUR, UTI, and renal parenchymal abnormalities all interact in a complicated way. The degree of renal parenchymal abnormality is the factor most predictive of long-term prognosis among the three, and the impact of post-UTI renal parenchymal abnormalities is expected to be minor in comparison to the congenital abnormality.


    Can I prevent vesicoureteral reflux?

    Although VUR cannot be prevented, excellent habits can help keep your child's urinary system as healthy as possible. Has your child screened for bladder infections and bladder control problems?

    • Drink enough liquids based on the doctor’s advice.
    • Maintain appropriate toilet habits, such as urinating on a regular basis and wiping from front to back.
    • If he or she is not toilet trained, his or her diaper should be changed as quickly as possible after it becomes filthy.
    • If required, get treatment for constipation. If at all possible, try to keep your youngster from being constipated.
    • Treated for linked health issues such as urinary or fecal incontinence.



    Urine normally passes from the kidneys through the ureters into the bladder and out through the urethra. VUR is a pediatric disease that is most commonly diagnosed in infancy and youth. When a child develops VUR, urine runs backward via one or both ureters from the bladder to the kidneys. Children with VUR who get a urinary tract infection run the risk of the infection spreading to their kidneys and developing pyelonephritis. These infections can lead to scarring and renal impairment. Increased scarring and renal damage can lead to reduced kidney function and elevated blood pressure over time.