What Is Vesicoureteral Reflux?

Vesicoureteral reflux (VUR) is when pee moves backward from the bladder to the kidneys. Normally, pee flows from the kidneys down to the bladder.

Kids with mild cases of VUR often don't need treatment. Those with more serious symptoms might need to take antibiotics to prevent infection. Kids who have infections and fevers along with the VUR might need surgery. But most kids don't have serious symptoms and outgrow the condition with no lasting problems.

What Happens in Vesicoureteral Reflux?

Thin tubes called ureters (YUR-uh-ters) connect the kidneys to the bladder, and carry urine (pee) to it. The bladder stores the urine until it's emptied when we pee. While urine is in the bladder, it doesn't usually flow back into the ureters. When we pee, urine leaves the body through the urethra (yoo-REE-thruh), a tube at the bottom of the bladder.

In vesicoureteral (ves-ih-koe-yoo-REE-ter-ul) reflux, pee backs up from the bladder into the ureters and sometimes to the kidneys.

What Are the Signs & Symptoms of Vesicoureteral Reflux?

Most kids with VUR don't show signs or symptoms. Often, doctors find the condition because a child has a urinary tract infection (UTI) with a fever.

A UTI lower in the urinary system (in the bladder) can cause:

  • frequent or urgent need to pee
  • bedwetting and pee accidents
  • a burning feeling while peeing
  • blood in the pee, or pee that looks cloudy or smells bad

A UTI higher in the urinary system (in the ureters or kidneys) can cause the same symptoms, as well as:

  • pain in the side or belly
  • fever and chills

What Causes Vesicoureteral Reflux?

Primary VUR is when defects in one or both ureters let pee flow the wrong way. Most kids with VUR have this type. Babies born with primary VUR have a ureter that didn't grow long enough before birth. This can affect where the ureter enters the bladder, letting pee flow back up the ureters to reach the kidney. Primary VUR is thought to be a genetic condition.

Secondary VUR is when a blockage in the urinary tract obstructs the flow of pee and sends it back into the kidneys. Kids with this type often have reflux in both ureters. This can happen because of nerve damage, infection, or pressure on the ureter from another organ.

How Is Vesicoureteral Reflux Diagnosed?

Sometimes, doctors find the condition before a baby is born during a routine prenatal ultrasound. The test might show that the baby has hydronephrosis/urinary tract dilation, which is swelling of the kidneys and along the urinary tract.

If your child has symptoms of a UTI, see a doctor right away. The doctor will do an exam, ask about your family medical history, and might order tests. These can include:

  • Blood tests and urine tests can see how well the kidneys are working and check for signs of infection or kidney damage.
  • An abdominal ultrasound uses sound waves to create images of the urinary tract. These might show a defect or blockage.
  • A voiding cystourethrogram (VCUG) is a test done while the patient pees. A technician fills the bladder with a special liquid, then takes X-rays while it is full and while it empties during peeing. Then, doctors compare the images to check for problems.
  • Contrast-enhanced voiding urosonography (ceVUS). As with VCUG, a catheter is placed and the bladder is filled with a special liquid. But an ultrasound is used instead of X-ray to get an image. This test uses no radiation.

If a child has VUR, the doctor will grade it from I through V. Grade I reflux is the mildest, with pee that backs up only as far as the ureters. Grade V reflux is the most severe.

How Is Vesicoureteral Reflux Treated?

Many kids with primary VUR outgrow it. As a child gets older, the ureter gets longer and straighter, and in time will shut correctly.

Doctors use antibiotics to treat VUR that happens with a UTI. This keeps the infection from spreading to the kidneys. Kids who take antibiotics should take them for as long as prescribed, even if they start to feel better. Some kids will take antibiotics every day as a way to prevent VUR.

Surgery

The doctor might talk to you about surgery that can help kids with moderate to severe cases of primary VUR with UTIs and fever. The most common type of surgery is ureteral reimplantation. In this procedure, the surgeon extends one or both ureters further into the bladder. This stops pee from flowing backward from the bladder to the ureters and kidneys. Kids who get this surgery usually spend a few days in the hospital while they recover.

Another surgery, endoscopic injection, involves injecting a special gel into the bladder through a thin tube. The surgeon places the gel into the opening of the ureter. This prevents pee from going back into the ureter and helps the ureter close properly. Most kids who have this procedure can leave the hospital on the same day.

Kids with secondary VUR might get antibiotics to fight infections and treatment for the main problem that led to the VUR.

What Else Should I Know?

Untreated VUR can lead to long-term problems. Backed-up pee that reaches the kidneys can scar them, causing:

Always call your doctor if your child has symptoms of a UTI, especially with a fever. Quick treatment of VUR can prevent long-term problems and kidney damage.

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