Defined as reflux of urine from the bladder cavity up into the ureters and sometimes into the renal pelvis, vesicoureteral reflux occurs during voiding or with elevation of pressure in the bladder.
Vesicoureteral reflux is common among children with anatomic abnormalities of the urinary tract as well as among children with anatomically normal but infected urinary tracts. In the latter group, reflux disappears with advancing age and is probably attributable to factors other than UTI. Long-term follow-up of children with UTI who have reflux has established that renal damage correlates with marked reflux, not with infection.
Vesicoureteral reflux (VUR) is the abnormal flow of urine from the bladder back into the ureters. Urine normally flows in one direction — down from the kidneys, through tubes called ureters, to the bladder.
VUR is most commonly diagnosed in infancy and childhood after the patient has a urinary tract infection (UTI). About one-third of children with UTI are found to have VUR. VUR can lead to infection because urine that remains in the child’s urinary tract provides a place for bacteria to grow. But sometimes the infection itself is the cause of VUR.
There are two types of VUR. Primary VUR occurs when a child is born with an impaired valve where the ureter joins the bladder. This happens if the ureter did not grow long enough during the child’s development in the womb. The valve does not close properly, so urine backs up (refluxes) from the bladder to the ureters, and eventually to the kidneys. This type of VUR can get better or disappear as the child gets older. The ureter gets longer as the child grows, which improves the function of the valve.
Secondary VUR occurs when there is a blockage anywhere in the urinary system. The blockage may be caused by an infection in the bladder that leads to swelling of the ureter. This also causes a reflux of urine to the kidneys.
Infection is the most common symptom of VUR. As the child gets older, other symptoms may appear, such as bedwetting, high blood pressure, protein in the urine, and kidney failure.
Common tests to show the presence of urinary tract infection include urine tests and cultures. Pictures of the urinary system (cystourogram) may then be needed to determine whether a defective structure in the urinary tract is the underlying cause of the VUR and infection.
The goal for treatment of VUR is to prevent any kidney damage from occurring. Infections should be treated at once with antibiotics to prevent the infection from moving into the kidneys. Antibiotic therapy usually corrects reflux caused by infection. Sometimes surgery is needed to correct primary VUR.