Which children are at risk and how likely is VUR to spontaneously resolve?

VUR is a common childhood anomaly

Vesicoureteral reflux (VUR) is the most common congenital urinary anomaly to occur during childhood.1 It usually presents during the first few years of life.

What puts a child at risk for VUR?2

Sibling or child of a person with VUR

Age, gender, race

Certain congenital anomalies or conditions of the kidney or pelvis

  • Agenesis
  • Multicystic dysplastic kidney
  • Pelviureteric junction
  • Distended kidney
  • Neuropathic bladder

Siblings of individuals diagnosed with VUR have a 30% probability of developing VUR3

The offspring of women diagnosed with VUR have a 50% chance of developing VUR2

For distended kidney, VUR is often identified prenatally or younger than 1 year old and is most often associated with boys2

Spontaneous resolution of VUR occurs more often in lower grades

VUR may spontaneously resolve over time; though, there is no definitive test to predict in which children. It is more likely to do so in children with lower grades of reflux.2

What is the likelihood of a child outgrowing VUR?

According to the American Urological Association:4

  • A child who is between the ages of 2-5 years old with grade III VUR (unilateral) has between a 13.4% (at 1 year) and 51.3% (at 5 years) chance of spontaneous VUR resolution
  • A child who is between the ages of 5-10 years old with grade III VUR (bilateral) has between a 2.6% (at 1 year) and 12.5% (at 5 years) chance of spontaneous VUR resolution
  • In patients aged 25 to 60 months with bilateral VUR grade III, only 30.5% of cases were resolved at 5 years

Antibiotic prophylaxis may be needed for a significant number of years in nearly half of the patients to protect them from a urinary tract infection (UTI) while their VUR persists. During this time, regular voiding cystourethrograms (VCUGs) are required to assess the condition. Also, the child is still at risk of breakthrough infections despite ongoing antibiotic treatment.

Age and gender matter in VUR resolution

The rate of spontaneous resolution of VUR decreases with increasing patient age. In a retrospective study, VUR resolved significantly slower in children over 13 months compared with children up to the age of 12 months (P<0.03).5

Boys with VUR have a greater likelihood of spontaneous resolution within the first year of life than girls.7 In one study, a resolution rate of 29% was reported in boys younger than 1 year with VUR grades IV and V. The same study reported that in both girls and boys after their first year of life, the annual reported resolution rate was only 9%.7

While high resolution rates have been reported for low grade VUR—one study reported spontaneous resolution rates of 82% for grade I VUR within 5 years8—resolution cannot be expected to occur universally. The longer a child goes without medical intervention, the more likely it is that he or she will suffer long-term consequences associated with VUR.

VUR may not resolve in time to prevent kidney damage

The longer the patient has had VUR, the less likely it is that VUR will resolve on its own, with or without antibiotic treatment.

  • Patients who experience VUR arising from febrile UTIs are at high risk for kidney scarring associated with infected urine coming into contact with the kidney.
  • In one study, children experiencing a first UTI have a 70% risk of developing acute kidney infection9

References:

  1. Chand DH, Rhoades T, Poe SA, Kraus S, Strife CF. Incidence and severity of vesicoureteral reflux in children related to age, gender, race and diagnosis. J Urol. 2003;170:1548-1550.
  2. Elder JS. Vesicoureteral reflux. In: Kliegman R, Nelson WE, eds. Nelson Textbook of Pediatrics. 19th ed. Philadelphia, PA: Elsevier/Saunders; 2011:1834-1838.
  3. Baskin LS, Kogan BA, Stock JA. Handbook of Pediatric Urology Third Edition. Philadelphia, PA: Wolters Kluwer; 2019.
  4. American Urological Association Pediatric Vesicoureteral Reflux Clinical Guidelines Panel. Report on the Management of Primary Vesicoureteral Reflux in Children. Linthicum, MD: American Urological Association; 1997.
  5. Smellie JM, Jodal U, Lax H, et al. Outcome at 10 years of severe vesicoureteric reflux managed medically: report of the International Reflux Study in Children. J Pediatr. 2001;139(5):656-663.
  6. Skoog SJ, Belman AB, Majd M. A nonsurgical approach to the management of primary vesicoureteral reflux. J Urol. 1987;138:941-946.
  7. Sjostrom S, Sillen U, Bachelard M, Hansson S, Stokland E. Spontaneous resolution of high grade infantile vesicoureteral reflux. J Urol. 2004;172:694–698.
  8. Arant BS Jr. Medical management of mild and moderate vesicoureteral reflux: followup studies of infants and young children. A preliminary report of the Southwest Pediatric Nephrology Study Group. J Urol. 1992;148:1683-1687.
  9. Lin KY, Chiu NT, Chen MJ, et al. Acute pyelonephritis and sequelae of renal scar in pediatric first febrile urinary tract infection. Pediatr Nephrol. 2003;18(4):362-365.