Vesicoureteral Reflux (VUR) - Topic Overview
What is vesicoureteral reflux (VUR)?
Vesicoureteral reflux (VUR) is the backward flow of urine from the
bladder into the
kidneys. Normally, urine flows from the kidneys
ureters to the bladder. The muscles of the bladder and
ureters, along with the pressure of urine in the bladder, prevent urine from
flowing backward through the ureters.
VUR allows bacteria, which
may be present in the urine in the bladder, to reach the kidneys. This can lead
kidney infection, scarring, and damage.
What causes vesicoureteral reflux?
There are two
types of VUR:
- Primary VUR is present
at birth. It is caused by a defect in the development of the valve at the end
of the tube that carries urine from the kidneys to the bladder (ureter). This
is the most common type of VUR and is usually detected shortly after
- Secondary VUR occurs when an
obstruction in the bladder or urethra causes urine to flow backward into the
kidneys. Secondary VUR can occur at any age and can be caused by surgery,
injury, a pattern of emptying the bladder that's not normal, or a past
infection that puts pressure on the bladder. It is more common in children who
have other birth defects, such as
What are the symptoms?
urinary tract infection (UTI) can be a symptom of VUR.
About one-third of children who are diagnosed with a UTI have VUR.1 Symptoms of a UTI may include fever, pain or burning with
urination, frequent urination, and the feeling that the bladder does not empty
completely. Fever may be the only symptom of a UTI in a small child. So a
urinary tract infection should be suspected in any child who has a high fever
without an obvious cause.
How is VUR diagnosed?
VUR is usually diagnosed
when a urinary tract infection (UTI) is suspected. Your doctor will ask about
the history of your child's symptoms and do a physical exam.
following tests may be recommended if UTI is suspected:
- A urine
culture, to check for a UTI
- Ultrasound of the kidneys. This test uses sound waves
to find out the size and shape of the kidneys. It can't detect reflux.
- Cystourethrogram (cystogram) after the
UTI has been treated. This test can detect VUR and help find out if it's mild
or severe. The
voiding cystourethrogram, for example, uses an X-ray
to take pictures of the
urinary tract . The bladder is filled with dye, and pictures are taken of the
bladder as it fills and empties.
VUR can be passed down from parent to child (inherited).
If one of your children has VUR, you may want to ask your doctor to check if your other
children have it too. Checking for VUR in siblings is especially helpful if your other child also has urinary tract infections. Doctors can use a cystourethrogram to see if babies
who have a sibling or parent with VUR also have the condition. But experts
disagree about screening for VUR, because the test involves going into the