Vesicoureteral Reflux (VUR)

What is vesicoureteral reflux?

Vesicoureteral reflux happens when urine dwelling in the bladder flows back into the ureters and often back into the kidneys. The bladder is the hollow, muscular organ that stores urine before urination happens. The bladder has 3 small openings; 2 connect the ureters where urine is drained down from the kidneys, and 1 connects the bladder to the urethra where urine exits the body.

The ureters are funnel-shaped tubes that carry urine from the kidneys. Ureters enter the bladder at a diagonal angle and have a special 1-way valve system that normally prevents urine from flowing back up the ureters in the direction of the kidneys. When a child has vesicoureteral reflux, the mechanism that prevents the backflow of urine does not work, allowing urine to flow in both directions. This condition is most frequently diagnosed in infancy and childhood. A child who has vesicoureteral reflux is at risk for developing recurrent kidney infections. This, over time, can cause damage and scarring to the kidneys.

What causes vesicoureteral reflux?


  • Having parents or siblings with VUR

  • Being born with neural tube defects like spina bifida

  • Having other urinary tract abnormalities, like posterior urethral valves, ureterocele, or ureter duplication

During infancy, the disease is more common among boys because as they urinate there is more pressure in their entire urinary tract. In early childhood, the irregularity is more common in girls. VUR is more common in white children than in African-American children.

What are the symptoms of vesicoureteral reflux?


  • Urinary tract infection. Urinary tract infections are uncommon in children younger than age 5. They are unlikely in boys at any age, unless VUR is present.

  • Trouble with urination including:

    • Urgency

    • Dribbling

    • Wetting pants

  • A stomach mass from a swollen kidney

  • Poor weight gain

  • High blood pressure

The symptoms of VUR may look like other conditions or medical problems. Always talk with your child's health care provider for a diagnosis.

How is vesicoureteral reflux diagnosed?

VUR can often be found by ultrasound before a child is born. If there is a family history of VUR, but your child has no symptoms, your child's health care provider may choose to do a diagnostic test to rule out VUR. Diagnostic procedures for VUR may include:

  • Voiding cystourethrogram (VCUG). A VCUG is a specific X-ray that examines the urinary tract. A catheter (hollow tube) is placed in the urethra. This is a tube that drains urine from the bladder to the outside of the body. The bladder is filled with a liquid dye. X-ray images will be taken as the bladder fills and empties. The images will show if there is any reverse flow of urine into the ureters and kidneys.

  • Renal ultrasound. This is a noninvasive test in which a transducer is passed over the kidney. It produces sound waves that bounce off the kidney and transmit a picture of the organ on a video screen. The test is used to determine the size and shape of the kidney, and to find a mass, kidney stone, cyst, or other obstruction or abnormalities.

  • Blood tests

What is the treatment for vesicoureteral reflux?

VUR can happen in varying degrees of severity. It can cause mild reflux, when urine backs up only a short distance in the ureters. Or, it can cause severe reflux leading to kidney infection(s) and permanent kidney damage. Specific treatment for VUR will be decided by your child's health care provider based on:

  • Your child's age, overall health, and medical history

  • The extent of the condition

  • Your child's tolerance for specific medicines, procedures, or therapies

  • Expectations for the course of the condition

  • Your opinion or preference


Most children who have grade 1 through 3 VUR do not need any type of intense therapy. The reflux resolves on its own over time, usually within 5 years. Children who develop frequent fevers or infections may need ongoing preventive antibiotic therapy and periodic urine tests. Surgical treatment is also available.

Children who have grade 4 and 5 reflux may require surgery. During the procedure, the surgeon will create a flap-valve apparatus for the ureter that will prevent reverse flow of urine into the kidney. In more severe cases, the scarred kidney and ureter may need to be surgically removed.

New treatments are being introduced for vesicoureteral reflux. Talk with your child's health care provider for more information.