What is reflux nephropathy

Reflux nephropathy is a condition in which the kidneys are damaged by the backward flow of urine into the kidney. One method of examining bladder function is by injecting dye that is visible on X-rays through a tube catheter to fill the bladder. X-rays are taken while the bladder is full and while the patient is urinating voiding to determine if fluid is forced out of the bladder through the urethra normal or up through the ureters into the kidney vesicoureteral reflux.

This study is usually done with the patient lying on an X-ray table. When the ureters enter the bladder, they travel through the wall of the bladder for a distance in such a way that they create a tunnel so that a flap-like valve is created inside the bladder.

This valve prevents urine from backing-up into the ureters and kidneys. In some children, the valves may be abnormal or the ureters in the bladder may not travel long enough in the bladder wall, which can cause vesicoureteral reflux. Vesicoureteral reflux is a condition that allows urine to go back up into the ureters and kidneys causing repeated urinary tract infections.

The reflux of urine exposes the ureters and kidney to infection from bacteria and high-pressure, which is generated by the bladder during urination. If left untreated, urinary infections can cause kidney damage and renal scarring with the loss of potential growth of the kidney and high blood pressure later in life. Vesicoureteral reflux is treated with antibiotics, and in severe cases surgically.

Urine flows from each kidney through tubes called ureters and into the bladder. When the bladder is full, it squeezes and sends the urine out through the urethra. No urine should flow back into the ureter when the bladder is squeezing.

Each ureter has a one-way valve where it enters the bladder that prevents urine from flowing back up the ureter. Over time, the kidneys may be damaged or scarred by this reflux. This is called reflux nephropathy. Reflux can occur in people whose ureters do not attach properly to the bladder or whose valves do not work well.

Children may be born with this problem or may have other birth defects of the urinary system that cause reflux nephropathy. Reflux nephropathy can occur with other conditions that lead to a blockage of urine flow, including:.

Reflux nephropathy can also occur from swelling of the ureters after a kidney transplant or from injury to the ureter. Some people have no symptoms of reflux nephropathy. The problem may be found when kidney tests are done for other reasons. Reflux nephropathy is often found when a child is checked for repeated bladder infections.

You cannot usually see the protein but it can be found on a urine test. If your child is found to have proteinuria , he or she will need regular urine tests. If there is reflux nephropathy in both kidneys bilateral reflux nephropathy , this may lead to long-term kidney problems. Your child will have regular blood tests to check how well his or her kidneys are working. Urine is made in each kidney and then passes through its ureter to the bladder.

The bladder fills up with urine, like a balloon. This is how we pass urine wee. As most people urinate wee , the end of each ureter that goes into the bladder squeezes tight. It acts like a one-way valve — urine can go into the bladder, but cannot leave the bladder back up the ureter. In VUR there is a problem with the way one or both ureters enter the bladder. This is usually present at birth. As children with VUR urinate, some urine refluxes goes back up one or both ureters, and may reach the kidney.

After urinating, this urine settles back into the bladder. In severe VUR, this means the bladder is never completely empty. VUR has 5 grades.

These depend how far urine refluxes up the ureter, and whether it is held up in the kidney. Grades 1 and 2 are mild, and Grades 3, 4 and 5 are more severe. Some children stay at the same grade for a long time, and a few get worse go to a higher grade.

The VUR gets better in more than half of children in the first few years of life. VUR is not caused by anything that the mother does during her pregnancy. It sometimes runs in families. If one of your children has VUR, your doctor may recommend that his or her brothers and sisters are also tested, especially if they have any complications such as frequent urinary tract infections UTIs.

VUR may happen on its own, though it is not always known why this happens. This is called primary VUR. VUR may be caused by, or happen with, another problem in the urinary system that makes it difficult to pass urine. This is called secondary VUR. Most of these problems are present at birth.

VUR may also happen with other kidney problems that develop while the baby is growing in the womb. These include renal dysplasia or renal hypoplasia , when one or both kidneys do not fully develop and are often smaller than usual.

Children may also be at risk of UTIs in the affected kidney, which may cause further damage. Reflux nephropathy is kidney scarring damage that is seen with VUR. This develops rarely in children with VUR who get kidney infections pyelonephritis , which may cause scars on the kidneys.

The 20 week antenatal ultrasound scan looks at the baby growing in the womb. This is due to the large amount of urine the fetus makes towards the end of the pregnancy, and it usually resolves gets better on its own. Sometimes, the swelling continues throughout pregnancy, and this may be caused by a number of conditions, including severe VUR.

Some babies with antenatal hydronephrosis are tested for VUR and other kidney conditions after birth. Your doctor will speak with you and your child about the symptoms and do a physical examination of your child.

Your child may need one or more imaging tests scans. These use special equipment to create pictures of the inside of his or her body. Your baby or child will probably first have an ultrasound scan to look at the kidneys and urinary system. This does not hurt your child. Another test that may be used instead for older children who are potty trained is an MAG3 scan with indirect cystogram. The chemical is taken up by healthy parts of the kidney. A large camera takes images.

Sometimes an MRI urogram is used instead. A special dye is injected into a blood vessel. Your child lies on a bed that passes into the MRI scanner, a large machine with a tunnel.

A urine test can diagnose a urinary tract infection UTI or find protein in the urine proteinuria. A dipstick will be dipped into the urine — this is a strip with chemical pads that change colour depending on what substances are in the urine.

The sample may also be sent to a laboratory for more accurate tests. Your child may need a blood test. A small amount of blood may be taken from a vein, with a needle and syringe. A special gel or cream can be used to help your child stop feeling any pain. The treatment depends on the grade of VUR how severe it is. Many children grow out of VUR, and treatment may only be needed for their early years before they go to school.

If your baby or child has VUR, he or she may be referred to a paediatrician , a doctor who treats babies, children and young people. Some babies and children with high-grade severe VUR or reflux nephropathy are referred to a paediatric urologist , a surgeon who treats children with problems of the urinary system.

The urologist will assess your child and consider whether treatment is needed. Occasionally, children are referred to a paediatric nephrologist , a doctor who treats children with kidney problems.

Children with VUR and reflux nephropathy are at higher risk of urinary tract infections UTIs , which may keep coming back recurrent. In serious cases, these may affect their kidneys. Children with high-grade VUR may benefit from taking a small dose of antibiotic medicine once a day — this is called a prophylactic antibiotic. Antibiotics kill bacteria germs that cause UTIs, and so help prevent these infections.

Sometimes UTIs can happen even when your child is taking these antibiotics. It is important that UTIs are diagnosed and treated quickly to try to prevent them causing kidney damage. Continue to give the antibiotics to your baby as your doctor has told you. If your child has high blood pressure hypertension , he or she may need to change what he or she eats and drinks. Some children need to take medicines. More about hypertension and how to control blood pressure. If the proteinuria persists or gets worse, your child may need medicines.

These will try to reduce the amount of protein lost in their urine and so protect the kidneys. Surgery is rarely needed. This aims to protect the kidneys from infections.

The first surgical procedure that is usually recommended is to inject a gel into the end of the ureter within the bladder. This narrows the space, preventing urine refluxing out of the bladder, without blocking urine flowing into the bladder. This is a quick procedure, and may be used for babies and children of any age.

Your child can usually go home the same day. Serious complications are very rare. However, no procedure is completely safe, and it is important you understand the risks.

Your urologist will speak with you about the possible problems before you consent agree to the procedure. Very occasionally, another operation called ureteric reimplantation is recommended.

This procedure re-tunnels the ureter into the bladder to create an anti-reflux mechanism — as should normally happen. A thin flexible tube called a catheter is placed through the urethra to drain urine from the bladder.

It is left in place for a few days until your child can pass urine on his or her own. This surgery is also done under general anaesthesia , so your child can sleep through the procedure and not feel any pain. Vesicoureteral reflux child. Mayo Clinic; Wein AJ, et al. In: Campbell-Walsh Urology.

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