VUR updates: Q&A with a pediatric urologist

VUR-leadThe American Urological Association (AUA) recently reviewed and validated the 2010 clinical guidelines, Management and Screening of Primary Vesicoureteral Reflux (VUR) in Children.

Although the guidelines remain intact, the AUA expanded its scope to include guidelines for the screening of siblings of children with VUR and of infants diagnosed prenatally with hydronephrosis.

Boston Children’s Urologist and Director of Quality and Safety, Caleb Nelson, MD, MPH, provides guidance on the detection and treatment of reflux in children, and offers clinical insight on the screening of siblings and those diagnosed prenatally with hydronephrosis.

When should a child be tested for VUR?

Children who get tested for reflux typically have conditions that are associated with an increased risk for reflux and renal damage, such as febrile urinary tract infection (UTI) and hydronephrosis. At Boston Children’s Hospital, our Department of Urology continues to recommend testing for reflux via voiding cystourethrogram (VCUG) or radionuclide cystography after the first UTI in many children.

Current American Academy of Pediatric (AAP) guidelines recommend VCUG after the second UTI. However, we think that’s overly cautious and may result in some children developing kidney injury due to delayed diagnosis. However, there are some reasons why you would choose to defer VCUG until the second febrile UTI. These reasons include:

  • most VUR is low grade and will resolve on its own
  • most children who have had an initial UTI will not have a recurrent UTI

Deferring the VCUG reduces the number of children tested, which could result in fewer children with benign disease being diagnosed and unnecessarily treated. This strategy also may result in recurrent UTI and kidney injury that might have been prevented had the child been tested and treatment initiated after the first UTI.

What are the guidelines for screening of siblings of children with VUR and of neonates/infants with prenatally diagnosed hydronephrosis?

Other cases to test for reflux in patients include children who have moderate to severe prenatal hydronephrosis or a family history (parents or siblings) of reflux. As a general rule, we don’t screen patients with a family history, but there are exceptions where you might opt to screen.

Sibling screening:  I would recommend screening siblings when there is a strong family history of reflux with renal disease or renal impairment (one or more family members with severe, high-grade VUR and renal scarring). It would also be reasonable to obtain an ultrasound, and if any abnormalities are identified, a VCUG would be appropriate at that time.

Neonate/infant screening: In newborns with moderate to severe hydronephrosis (SFU grade 3 or 4, or UTD scale 2 or 3), I recommend a VCUG. The risk of VUR is actually similar across all degrees of hydronephrosis, but infants with severe hydronephrosis are likely have some degree of concurrent obstruction, and the combination of VUR with concurrent obstruction may lead to more frequent or severe UTI episodes. Therefore, in such children we do recommend the VCUG be performed to assess for VUR. Another group in which we generally recommend VCUG is those with hydroureteronephrosis, because those children are at significantly increased risk of having reflux, compared to infants with renal dilation but no ureteral dilation. Such children should undergo VCUG even if their hydronephrosis is not severe.

When should antibiotic prophylaxis be prescribed?

VUR-severe
Severe VUR

Most kids have low-grade reflux and the majority of cases will resolve and not require surgery. Traditionally, we have used antibiotic prophylaxis in children with VUR to reduce risk of UTI until the VUR has resolved. Today, however, there is recognition that prophylaxis is probably not necessary in every child with VUR. Children we will consistently start on prophylaxis include:

  • children with higher-grade VUR (grade 3 and higher)
  • history of kidney injury or documented renal scarring
  • history of severe or prolonged febrile UTI
  • documented bowel and bladder dysfunction (which should also be addressed)

Patients less likely to need prophylaxis are those at a lower risk for recurrent infections. That would include children with:

  • very low-grades of reflux (1 or 2)
  • no history of UTIs but diagnosed some other way, such as through sibling screening
  • no sign of voiding dysfunction or bowel or bladder dysfunction
  • no renal scarring or damage

In those populations, it is reasonable to follow those children without prophylaxis. However, it is critical that families understand children with VUR need prompt evaluation of any febrile episode to rule out UTI, whether or not they are on prophylaxis.

Any new information regarding treating UTI?

There was a follow-up study using data from the RIVUR study that showed that among children with febrile UTI, the risk of new renal scarring increased with increasing time from onset of fever to initiation of antibiotic treatment. These findings confirm what we have suspected for many years — time is important in treatment of pyelonephritis. Children who went 48-72 hours before initiation of treatment had a much higher risk of kidney scarring than if the antibiotics were started within 24 hours.

It’s not easy to differentiate between kids who have a UTI and those who don’t. Girls, uncircumcised boys, Caucasians, and infants with very high or prolonged fever are at higher risk of UTI. Ideally, those at increased risk of UTI should have their urine checked at presentation, before you assume that the fever is due to some other source that does not require antibiotics. This is particularly true for those children already known to have VUR.

Who is at higher risk of UTI recurrence?

The groups that are at higher risk for recurrence are children with high-grade reflux, history of recurrent infections, history of renal scarring, or bowel or bladder dysfunction. In these cases, I strongly recommend prophylaxis.

When to refer

We recommend referring a patient to a pediatric urologist if the child has the following:

  • higher-grade reflux
  • persistent reflux
  • other anatomic issues including hydronephrosis, kidney abnormalities, urinary function issues and recurrent UTI

Depending on the pediatrician’s comfort level, they can refer to a urologist after the first UTI.Depending on the your comfort level, pediatricians can refer to a pediatric urologist after the first UTI. You don’t have to do the workup. But for those who are comfortable, you can manage kids with lower-grade reflux and send them to a specialist if the child’s condition does not improve. It really depends on what your comfortable level and how much of the condition you want to manage.

Additional resources

Learn more about Boston Children’s Department of Urology.

About our expert:

Nelson-VUR

 

Caleb Nelson, MD, MPH, an associate in Urology, director of Quality and Safety, co-director of the Kidney Stone Program in Boston Children’s Department of Urology