Vesicoureteral reflux (urinary reflux) is a childhood condition in which urine flows the wrong way from the bladder into the kidneys.
Vesicoureteral reflux occurs in around one in 100 children. The majority of children with the condition will not require any treatment and will grow out of the condition during childhood. However, some may require medication or surgery to prevent kidney damage.
The kidneys, ureters, bladder, and urethra form the urinary tract. The kidneys remove waste products and fluid from the blood to produce urine. The urine travels from the kidneys, down two narrow tubes called the ureters, to be stored in the bladder until a person urinates.
Normally, urine is prevented from flowing back up the urinary tract by valves that close when a person is emptying their bladder. With vesicoureteral reflux the valves do not work properly, which allows urine from the bladder to flow back up the ureters and into the kidneys.
Refluxing urine increases pressure within the kidneys and may contain bacteria that can lead to infections. Increased pressure and repeated infections can lead to damage and scarring of the kidneys which can interfere with kidney development and kidney function later in life.
Vesicoureteral reflux is usually a congenital condition (present at birth) that results in one or both valve mechanisms not working correctly. The condition is more common in girls than boys.
Signs and symptoms
Vesicoureteral reflux itself does not produce any symptoms. Symptoms occur when infection of the urinary tract (UTI) is present. Infection causes symptoms such as fever, pain, unpleasant smelling urine and a burning sensation when urinating.
Other symptoms commonly experienced include:
- Lower abdominal pain
- Blood or pus in the urine
- Kidney failure.
Vesicoureteral reflux may be suspected before a baby is born if prenatal ultrasound scans show enlargement of the kidney(s) and widening of the ureter(s).
Vesicoureteral reflux is more commonly found during infancy with the occurrence of repeated urinary tract infections. Up to 30% of children who experience UTIs have some degree of urinary reflux.
Common investigations used to diagnose vesicoureteral reflux and look for kidney damage include:
- Ultrasound scanning: The bladder and kidneys are scanned to identify any irregularities.
- Micturating cystourethrogram (MCU): A small tube (catheter) is put into the child’s bladder and a liquid that is visible on x-rays is passed into the bladder. X-rays are taken as the bladder fills and as the child urinates.
- Nuclear medicine scan: A liquid is injected into the bloodstream which enables a specialised scanner to take pictures that help doctors assess kidney size, position, function and the presence of scarring.
The goal of any treatment for vesicoureteral reflux is to prevent damage to the kidneys.
Treatment will depend on the severity of the reflux and whether there are ongoing problems with infection. In most cases, treatment is unnecessary and the child's doctor will simply monitor the growth and health of the child’s kidneys with ultrasound scans. It may be recommended that the child has regular urine tests to make sure there is no infection present.
If treatment for vesicoureteral reflux is required, there are two main treatment options:
UTIs require prompt treatment with antibiotics to prevent infection developing in the kidneys. In children who have recurrent UTIs, preventative antibiotics may be recommended to stop UTIs from developing, and hence prevent damage to the kidneys. The health and growth of the kidneys will be regularly assessed with ultrasound scans.
Whilst surgery is no longer done routinely for vesicoureteral reflux, a small number of children will require surgery to correct the problem. This is particularly so for children with severe vesicoureteral reflux who:
- Continue to develop UTIs while taking antibiotics
- Are allergic to the antibiotics
- Get worse reflux over time
- Show signs of kidney damage.
Surgery to repair the valve mechanism is performed under a general anaesthetic and may require a 2-3 day stay in hospital. During surgery, the ureters are released and are then “re-implanted” into the bladder wall in such a way that an efficient valve mechanism is created.
Antibiotic treatment to prevent infection may be continued after surgery until follow-up assessment shows that the reflux has resolved. The operation has a very high rate of success for the treatment of vesicoureteral reflux.
Further information and support
Kidney Kids is a group of New Zealand parents and children, who are dealing with kidney issues. Kidney Kids has support groups and contacts throughout New Zealand.
Freephone: 0800 215 437
Email: [email protected]
Kidney Health New Zealand provides education and support about different kidney diseases. Their website provides details of patient support centres in New Zealand.
Kidney Health New Zealand
Freephone: 0800 KIDNEY / 0800 543 639
Email: [email protected]
KidsHealth (2018). Urinary reflux (Web Page). Auckland: Paediatric Society of New Zealand and Starship Foundation. https://www.kidshealth.org.nz/urinary-reflux [Accessed: 28/08/20]
Mayo Clinic (2020). Vesicoureteral reflux (Web Page). Rochester, MN: Mayo Foundation for Medical Education and Research. https://www.mayoclinic.org/diseases-conditions/vesicoureteral-reflux/symptoms-causes/syc-20378819 [Accessed: 28/08/20]
O’Toole, M.T. (Ed.) (2017). Vesicoureteral reflux. Mosby’s Dictionary of Medicine, Nursing & Health Professions (10th ed.). St Louis, MI: Elsevier.
Last reviewed: August 2020
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