What is Vesicoureteral Reflux?
Vesicoureteral reflux is a common disorder of the urinary system. The urinary system
is made up the kidneys, ureters, bladder and urethra. The body has two kidneys that
drain urine to the bladder by small tubes called ureters. Urine normally travels
in only one direction, i.e from the kidneys to the bladder. Vesicoureteral reflux
(VUR) occurs when urine travels backward from the bladder through the ureters to
the kidneys. Vesicoureteral reflux without urinary infection by in large is harmless.
However, when associated with urinary infection, VUR may cause severe kidney infections
(pyelonephritis) which can lead to kidney damage.
What Causes Vesicoureteral Reflux?
There are two types of VUR: primary and secondary. Primary VUR is the most common
and is usually caused by an irregular embryological arrangement of the ureteral
tube in the bladder early in the development of the fetus before birth. When the
ureter enters the bladder, the tunnel for which it travels in the bladder may be
too short or have too large of a diameter to allow the ureter to close sufficiently
during bladder filling to prevent a backup of urine. This condition may resolve
as the child grows with the bladder enlarging and the ureter changes in length.
Secondary VUR occurs when there is an associated condition, such as: bladder outlet
obstruction, overactive bladder, myelomeningocele, voiding abnormalities and dysfunctional
Who is Susceptible to Vesicoureteral Reflux?
VUR occurs in less than 1% of healthy children. In children with a urinary tract
infection (UTI), the incidence is 25 to 50%. One study found that 38% of children
with antenatal (before birth) kidney swelling (hydronephrosis) were diagnosed with
VUR on subsequent studies after birth. While boys had a higher incidence antenatally,
females still make up 85% of the children with VUR overall. Caucasian girls had
10 times the risk of VUR versus African-American girls.
Further studies have shown a higher incidence of VUR (30-40%) in siblings of children
who were already diagnosed with VUR. If you have a child with vesicoureteral reflux,
it is important to talk with your physician to determine if other siblings should
be evaluated for VUR.
How is Vesicoureteral Reflux Diagnosed?
There are two different types of patients who are diagnosed with VUR; 1- children
with prenatally detected kidney swelling (hydronephrosis); 2- Children being evaluated
for urinary tract infection. Some children are detected before birth when hydronephrosis
is discovered via a prenatal screening ultrasound. These children are frequently
evaluated after birth with a renal ultrasound and voiding cystourethrogram (VCUG).
A VCUG is performed by placing a catheter in the urethra (natural voiding channel)
and X-ray visible dye is injected into the bladder allowing X-rays to delineate
the flow of the urine.
The second group of children may require an evaluation for VUR after a urinary tract
infection. While opinions vary, it is generally accepted that the following children
with a UTI should be evaluated for VUR with a renal ultrasound and VCUG: any child
less than 5 years of age, a child with a UTI and fever (regardless of age), and
any boy with a UTI (unless they are sexually active or have a significant past history
of genitourinary problems).
Your healthcare provider may recommend another form of imaging called a radionuclide
scan. This procedure allows the provider to continue to monitor the VUR with minimal
radiation exposure. A DMSA scan may be ordered to detect scarring of the kidney
or an infection in the kidney (pyelonephritis).
The VCUG is important in helping to stage the severity of VUR.
- Grade I: urine refluxes into the ureter only
- Grade II: urine refluxes into the ureter and renal pelvis (collecting system of
the kidney) without distention of the pelvis.
- Grade III: urine refluxes into the ureter and renal pelvis with only mild dilatation
- Grade IV: the child also has moderate hydronephrosis
- Grade V: The child has severe hydronephrosis and abnormalities of the ureter.
What are the Symptoms of Vesicoureteral Reflux?
Vesicouretral reflux itself is usually asymptomatic and a urinary infection is the
presenting picture. Children may present initially with the following signs of a
urinary tract infection: fever, malodorous urine, blood in the urine, urinary frequency,
pain with urination, bedwetting, protein in the urine, lethargy or gastrointestinal
symptoms. Newborns may have nonspecific symptoms such as poor feeding and irritability.
What are the Complications of Vesicoureteral Reflux?
Vesicoureteral Reflux without urinary infection for the most part does not cause
injury to the kidneys. However, VUR with infection can result in an infection of
the kidney (pyelonephritis) which can result in scarring of the kidney. Fortunately,
significant kidney scarring is rare. Significant scarring of the kidneys can result
in high blood pressure, renal impairment, renal failure, and complications in pregnancy
as an adult. Prophylactic antibiotic treatment to prevent urinary infections in
children is begun immediately after diagnosis of VUR to try and decrease the risk
for these complications.
How is Vesicoureteral Reflux Treated?
The management and treatment of VUR depends upon many factors and an in depth discussion
of VUR and your child should be individualized with your health care provider. Vesicoureteral
reflux is frequently initially managed by a primary care provider for lower grades
of VUR (1-3) . Higher grades of VUR or complex and complicated cases of VUR are
usually jointly managed with a surgical specialist called a Pediatric Urologist.
VUR has a spontaneous resolution rate and is usually managed with prophylactic antibiotics
(preventative antibiotic) in hope that with growth of the child there will be concomitant
growth of the ureteral tunnel. Should the tunnel grow enough then the VUR may resolve
without the need for a surgical procedure. Prophylactic antibiotics are given at
very low doses daily to reduce possible side effects. Newborns are usually given
Amoxicillin or Keflex (Cephalexin). Children older than 2 months can be given Trimethoprim
(Primsol) or Bactrim (trimethoprim-sulphamethoxazole). Waiting 12-18 months is the
usual time to wait between follow up X-rays so that a child has time to grow.
Spontaneous resolution of VUR has one major caveat. It is impossible to predict
when or if the VUR will improve or resolve. Some children with high grade VUR can
have resolution in a short time frame and some children with low grade VUR will
never have spontaneous resolution. Fortunately most children with Grades I-III VUR
will have improvement or resolve their urinary reflux by the time they are 2 to
5 years of age. Children with Grades IV & V urinary reflux have a lower resolution
rate of VUR. These children too can be followed but frequently require a surgical
procedure to bring closure to the VUR
When is Surgery recommended for VUR?
If a child has a breakthrough infection (urinary tract infection on the preventative
antibiotic) the conservative plan of monitoring the reflux must be abandoned and
a surgical procedure is necessary to prevent further potential infections of injuring
the kidneys. In general infants are at greater risk for renal injury than older
Surgery is also an option if a child has had persistent VUR after years of follow-up
with little or no improvement. However, if no infections have occurred surgery is
not mandatory. In the older child, many families frequently select surgery to bring
closure to the problem, allow the discontinuance of antibiotics, and avoid any further
potential side effects of VUR.
What type of Surgery is available for VUR
Surgical treatment is offered in 2 ways; open ureteral reimplantaion surgery and
minimally invasive endoscopic deflux injections. The gold standard is open surgery
that involves rearranging the ureters in the bladder in a non-refluxing natural
position. Open surgery is > 95% successful and usually does not require a repeat
VCUG x-ray after surgery. The surgical procedure is performed through a 4cm low
abdominal incision, just above the pubic bone, below the underpants line. The child
routinely only spends the night of surgery in the hospital and generally gets back
to normal activity in 3-5 days (4-6 years old). Infants and toddlers rarely need
surgery but, if required, are frequently back to themselves within 1-2 days.
Minimally invasive deflux injection involves performing a telescopic exam (endoscopic)
of the bladder through the urethra as an outpatient procedure. This access allows
direct injection of a dextramoner bead paste (sugar beads) under the ureter that
improves or cures VUR in about 80% of the time. Children are back to normal activity
usually the same day. A VCUG x-ray is necessary to assess the treatment after the
About the Author
Peter D. Furness III, M.D., FAAP, FACS:
Dr. Furness is Associate Professor of Surgery and Pediatrics at the University of
Colorado Health Sciences Center and the Associate Chief of Pediatric Urology at
the Children's Hospital in Denver, Colorado.
Copyright 2012 Peter D. Furness III, M.D., All Rights Reserved