Vesicoureteral reflux (VUR) is the backward flow of urine. The urine flows from the bladder back into the ureters or kidney.

Types of VUR:

  • Primary—direct result of structural or genetic defects that affect the urinary tract
  • Secondary—results from underlying causes, such as infection, or problems in the urinary tract that lead to restricted urine flow
Anatomy of the Urinary System
The Urinary Tract
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Urine normally flows from the kidneys. It passes through tubes called ureters and into the bladder. Each ureter connects to the bladder in a way that prevents the backflow of urine. The connection is similar to a one-way valve. When the valve does not work properly, or if the ureters do not extend far enough into the bladder, urine may flow back up the ureter and into the kidney.

Most VUR results from residual, undected childhood disease, but may have other causes. Some examples include:

  • Neurogenic bladder—nerve damage that inhibits normal bladder function
  • Obstruction in the urinary tract
  • Genetic defects inherited from your family
  • Structural or functional abnormality of the urinary system acquired as you age
  • Herniation of the ureter as it enters the bladder—ureterocele
  • Kidney transplant

Risk Factors

VUR is more common in women and in those who are Caucasian. Other factors that may increase your chances of VUR include:


Generally, VUR has no symptoms and can remain undetected into adulthood. In some, it is found after a urinary tract or kidney infection is diagnosed and evaluated. Flank pain may be present during the time the bladder is filling with urine.

Complications of undetected or untreated VUR include:

  • Problems with normal kidney function—scarring from backed-up urine causes damage to structures in the urinary tract, including the kidneys
  • High blood pressure
  • Pregnancy complications, including an increased risk of urinary tract or kidney infections, gestational diabetes, preeclampsia, and premature labor
  • Acute or chronic kidney failure


You will be asked about your symptoms and medical history. A physical exam will be done. Your doctor may suspect VUR based on your history. Many times VUR is found incidentally during testing for another problem, such as high blood pressure, kidney stones, neurogenic bladder, other urinary problems, or abdominal pain.

If your doctor suspects VUR, a voiding cystourethrogram (VCUG) is usually done. VCUG is an imaging test that evaluates structures during urination. Other tests may include:

  • Blood tests
  • Urine tests and cultures
  • Bladder x-ray—cystography
  • Kidney ultrasound
  • Nuclear scans


VUR in adults does not usually resolve over time. The goal for treatment of VUR is to reduce or stop the back up, and prevent additional and permanent damage. Treatment depends on the severity of VUR and may include one or more of the following options:


Medications can be used to:

  • Treat prevent or treat infections (antibiotics)
  • Manage high blood pressure
  • Reduce the amount of protein in the urine
  • Treat underlying causes of VUR, such as bladder and/or bowel dysfunction


Surgery may be done for more severe VUR or in cases when other treatment methods fail. Procedures include:

  • Endoscopic injection into the ureter—Material is injected where the ureter inserts into the bladder. This can prevent urine from going back up into the ureter. It is done during a procedure called a cystoscopy.
  • Ureteral reimplantation—Repositions the ureters in the bladder. It can be done as an open or laparoscopic procedure.


To help reduce your chances of VUR:

  • Seek prompt treatment for any urinary problems, including a bladder or kidney infection.
  • If you are pregnant, go to any recommended prenatal screenings as advised by your doctor.
  • If you are prone to frequent urinary tract or kidney infections, ask your doctor about prophylactic antibiotics to prevent infection.

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