Vesicoureteral reflux at a glance
- Vesicoureteral reflux (VUR) is the backward flow (reflux) of urine from the bladder to the kidneys, instead of flowing to the ureter tubes and out the body.
- The valve that normally prevents urine reflux is called the vesicoureteral (ves-ih-ko-yoo-REE-tur-ul) valve.
- Vesicoureteral reflux occurs in infants and children, affecting about 1 percent of children and sometimes continuing beyond puberty.
- VUR can be difficult to diagnose, generally presenting symptoms only after it has resulted in a urinary tract infection (UTI).
- Children with VUR are susceptible to kidney infections and kidney damage, as a UTI spreads more easily to the kidneys.
- Many children outgrow vesicoureteral reflux.
- The goal of treatments, usually medications or surgery, is to prevent kidney infection and damage.
What is vesicoureteral reflux?
Vesicoureteral reflux (VUR) is a urinary tract condition in which urine flows back to the kidneys from the bladder, rather than flowing from the bladder and out of the body through the ureter tubes through the vagina or penis. In mild cases, urine only flows into the urethra tubes that connect the bladder and kidneys.
The purpose of the kidneys is to filter waste from the blood stream and produce urine to flush those impurities from the body. When that urine reverses flow from the bladder and goes back to the kidneys, bacteria sometimes present in the urine can cause a urinary tract infection (UTI).
The danger for children with VUR is that a resulting UTI weakens the urinary tract’s ability to prevent bacteria from entering the kidney, which can result in kidney damage and infection. These are serious conditions that can result in death due to acute infection and scarring of the kidney (reflux nephropathy). Kidney scarring can also lead to high blood pressure.
Vesicoureteral reflux occurs in about 1 percent of children. VUR can be difficult to diagnose and is usually diagnosed after a UTI presents symptoms in the child. UTI symptoms are difficult to assess in children.
VUR generally presents in two ways: symptoms from a UTI or symptoms from hydronephrosis, which is a swelling of the kidney due a build up of urine. Hydronephrosis may be detected in a fetus through ultrasound. Usually, the more urine that flows back to the kidneys, the greater the risk of complications.
There are two types of VUR, primary and secondary. Primary VUR is due to a birth defect in the vesicoureteral valve that usually prevents such backflow of urine. Secondary VUR occurs at any age and is caused by a urinary tract problem, generally due to infection.
VUR is graded according to the amount of urine that flows back to the kidneys. In mild cases (grade I) urine only backs up into the ureters, the tubes that connect the bladder to the kidneys. In aggressive VUR (grade V) urine causes the kidney(s) to swell (hydronephrosis).
Risk factors for vesicoureteral reflux
- Girls are twice as likely to have VUR as boys
- Often runs in families, particularly if the child’s parent(s) had VUR
- More prominent in white children
- Children under 1 year old are more likely to have VUR.
Symptoms of vesicoureteral reflux
Vesicoureteral reflux itself has few outward symptoms, most notably tenderness in the abdomen or flank and swelling of the kidneys (hydronephrosis), which generally causes pain. VUR is often noticed by the symptoms of a UTI that occurs due to bacteria in the urine that flows backward to the kidneys.
Infants may indicate a UTI by showing a fever, diarrhea, no appetite, irritability or “failure to thrive,” meaning lower weight and slower growth than normal. Children also often have nonspecific symptoms.
UTIs generally cause the following symptoms:
- Urination problems — strong urges, burning sensation, frequent urges but small amounts
- Blood in urine
- Pain in the belly or sides
- Vomiting, diarrhea
- Lethargy (lack of energy).
The signs and symptoms above are reasons to seek medical attention. Children with VUR are at an elevated risk for kidney infection and damage.
Diagnosis and treatment of vesicoureteral reflux
A lab urinalysis is usually the first step in determining if a child has VUR. Doctors may also order other scans and screenings, including ultrasounds of the kidney and bladder or x-rays to evaluate bladder efficiency (voiding cystourethrogram).
Treatment for vesicoureteral reflux
In some children VUR goes away with no treatment. This is more likely in younger children and in less severe cases. Older children with VUR who have not had a UTI may not receive treatment other than medical surveillance.
When treatment for VUR is required, antibiotics are generally the fist line treatment to stop the UTI. Preventive antibiotic medications may be given after the UTI has cleared, but it is not certain that these are effective.
Surgery can reconstruct the area where the ureter connects to the bladder. This lengthens the ureter tunnel and allows it to act as a valve that closes as the bladder fills, preventing urine reflux.
Surgery may be open (traditional incisions), minimally invasive surgery (through use of a special scope called a laparoscope, utilizing small incisions, special instruments and a video view of the surgical area), or robotic laparoscopic surgery.
Reasons for surgery include:
- Insufficient kidney growth
- New scarring of the kidneys
- Continued UTIs in spite of medications
- High-grade VUR unlikely to resolve, particularly if kidney scarring occurs
- Females approaching puberty with persistent VUR.
Risks from VUR surgery include those for any surgery: blood loss, infection, pain, damage done to organs or tissue, and complications due to anesthesia.