Vesicoureteral Reflux (VUR) in Children

Dr. Tanmay Motiwala
Pediatric Surgeon, Raipur · Updated 30 Sep 2026 · 7 min read

Your child has had one urine infection after another, often with high fever. So now the doctor wants special scans of the kidneys and bladder. You may ask why a simple urine infection needs so many tests. The answer is that in some children the infections keep coming back for a reason. Urine is flowing the wrong way, back up toward the kidney. Doctors call this vesicoureteral reflux.

The short name is VUR. Below, I explain what it is and why it matters for a child’s kidneys. I also explain why doctors do the scans and how they treat it. And you will see why most children do not need an operation.

What Is Vesicoureteral Reflux?

The kidneys make urine. Then it travels down two tubes (the ureters) into the bladder. Each tube enters the bladder through the bladder wall at a slant. As a result, this forms a natural one-way valve. When the bladder squeezes to empty, that valve normally stops urine from going back up.

In a child with VUR, that valve is short or weak from birth. So when the bladder squeezes, some urine goes back up the ureter. In worse cases, it goes all the way up to the kidney. Your child did nothing to cause it. It is simply how the valve formed.

Why Vesicoureteral Reflux Matters

Reflux by itself is not the danger. The problem is reflux plus infection. If the urine in the bladder has germs, the backward flow carries them up to the kidney. This causes a kidney infection (pyelonephritis) with high fever. Over time, repeated kidney infections can leave scars on the kidney.

We must be honest about this part. Over many years, bad kidney scarring can lead to high blood pressure. In a small number of children, it can also lead to weaker kidney function. That long-term risk is the real reason doctors take repeated urine infections with fever seriously in a young child. It is not about this week’s infection. So doctors look for reflux. Finding and managing it protects the kidneys for life.

Scans for Vesicoureteral Reflux

The scans answer three questions. Are the kidneys normal? Is there reflux? Has any damage already happened? The usual tests are:

Ultrasound (USG) — a painless, safe scan that uses sound waves. It looks at the size and shape of the kidneys and bladder. It is usually the first step.
MCU / VCUG (micturating cystourethrogram) — a special X-ray while the bladder fills and empties. It is the only test that actually shows reflux. It also grades how bad it is.
DMSA scan — a kidney scan that shows whether any scarring has already formed.

Doctors grade reflux from I to V. Grade I is very mild: urine backs up only into the lower tube. Grade V is severe: the whole system is swollen and stretched. In turn, the grade guides the plan. Lower grades very often go away on their own as the child grows. Higher grades more often need treatment and carry more risk of scarring.

Treating Vesicoureteral Reflux: Most Children Avoid Surgery

The most important message for parents is this: the first treatment is usually not an operation. Most mild and medium reflux goes away by itself over a few years. So the usual plan is to protect the kidneys while waiting for the valve to grow stronger:

A small daily dose of antibiotic (prophylaxis). This keeps the urine free of infection. Also, your child has regular follow-up scans.
Fixing constipation and toilet habits. People often miss this, but it matters a lot. Some children are constipated, or they hold urine and do not empty the bladder fully. This makes reflux worse. So treating constipation and teaching relaxed, full bladder emptying is a real part of the treatment.

Surgeons keep surgery for children who truly need it. These children keep getting kidney infections despite the daily antibiotic. Or they have high-grade reflux and kidney scarring, or reflux that simply does not go away with time. In that case, there are two main options:

Endoscopic injection (Deflux). The surgeon passes a thin telescope into the bladder, with no cut. Your child goes home the same day. The surgeon injects a small amount of gel to support the weak valve. It works well for milder reflux (about 8 in 10 for low grades). But success falls as the grade rises (about 2 in 3 for grade IV).
Reimplantation surgery. In this operation, the surgeon rebuilds the valve. He or she makes a new tunnel for the ureter through the bladder wall. In fact, it is the most reliable option. It works in about 98 to 99 out of 100 children. It is the lasting choice for severe or stubborn reflux.

A Few Other Things Worth Knowing

VUR can run in families. Brothers and sisters of a child with VUR have a higher chance of having it too. So doctors may suggest checking a younger brother or sister who gets urine infections. Doctors also look for VUR when a child has repeated urine infections with fever. They also look for it when an earlier scan showed a swollen kidney. That is why doctors follow these children carefully.

What Every Parent Must Know

Vesicoureteral reflux means urine flows backward from the bladder toward the kidney. The valve is weak from birth. Your child did nothing to cause it.
The danger is reflux plus infection. Together, they can scar the kidney. Over years, it can raise the risk of high blood pressure and weaker kidney function.
Doctors use the scans (ultrasound, MCU/VCUG, DMSA) to find reflux, grade it, and check for scarring. They are not extra tests for nothing.
Most children do not need surgery. Daily antibiotics, treating constipation, and time cure most of them. Surgery is for infections that break through, high grades, or scarring.

When to See a Pediatric Surgeon

See a pediatric surgeon or pediatric urologist if your child has had more than one urine infection with fever. Also go if a urine infection came with high fever and back or tummy pain. And go if a scan has shown reflux, a swollen kidney, or kidney scarring. An early check protects the kidneys. It often avoids the need for surgery at all.

Dr. Tanmay Motiwala is a pediatric surgeon in Raipur, Chhattisgarh, trained at AIIMS Jodhpur. He evaluates recurrent urine infections and kidney problems in children from across Chhattisgarh and central India, and can advise which scans are needed and whether treatment can safely wait, or whether surgery is required.

Related reading:

My Child Keeps Getting Urine Infections — Is There a Kidney Problem?
The Scan Shows My Baby’s Kidney Is Swollen — What Is Antenatal Hydronephrosis?
Phimosis in Boys: When Does Tight Foreskin Actually Need Treatment?

📋 This article is part of Dr. Motiwala’s Pediatric Urology in Raipur services — see the full range of conditions treated, what to expect, and when to see a pediatric surgeon.

My Child’s Urine Infections Keep Coming Back — Could Urine Be Refluxing to the Kidney?