Once reflux is confirmed the questions change. How much risk does this child carry, and what should be watched, and for how long? From here on the AUA and EAU/ESPU guidelines are at the centre; the AAP 2026 guideline joins only for the definition of risk, and NICE only for kidney follow-up.

The question for this part

Does labelling a child high-risk actually pick out the children who do badly? And what still needs watching after the reflux has gone?

1. What is assessed at diagnosis?

Both guidelines ask for more than the reflux grade: renal status and bladder and bowel function are assessed alongside it. The EAU/ESPU baseline is a history including family history and screening for lower urinary tract dysfunction (LUTD), blood pressure, urinalysis for proteinuria and a urine culture, and serum creatinine when both kidneys are abnormal. Imaging is based on ultrasound, VCUG and nuclear medicine, with the DMSA scan at diagnosis serving as the baseline for later comparison. The AUA makes height, weight, blood pressure and creatinine in bilateral abnormality a Standard; urinalysis and ultrasound a Recommendation; and baseline creatinine and DMSA an Option.

The clearest agreement is on BBD. EAU/ESPU rates as Strong a detailed assessment for LUTD in every child, particularly after toilet training, with LUTD treated first if present; the AUA makes looking for symptoms of BBD at the initial evaluation a Standard. In the AUA meta-analysis BBD made a large difference to the course. On antibiotic prophylaxis, reflux resolved in 31% of children with BBD versus 61% without; after endoscopic treatment, in 50% versus 89%. Only open surgery showed no difference, at 97% in both groups.

2. How do the three guidelines stratify risk?

It is EAU/ESPU that puts risk stratification at the heart of its guideline. The early risk classification proposed by Tekgül and colleagues in 2012 became Table 3 of the current VUR chapter. It uses five axes — symptoms, toilet-training status, reflux grade, renal abnormality and LUTD — to build nine rows, each with an initial treatment and a time for re-evaluation. The panel admits that the table is complex, but adds that simpler guidance underestimates the complexity of reflux.

Risk groupPresentationInitial treatmentFollow-up / re-evaluation
HighSymptomatic after toilet training; high grade (IV–V), abnormal kidneys, LUTDTreat LUTD, with CAP. Consider intervention for breakthrough infection or persistent refluxClose UTI and LUTD follow-up; re-evaluate at 6 months
HighSymptomatic after toilet training; high grade, abnormal kidneys, no LUTDConsider intervention. Reimplantation gives better results than endoscopic treatmentPostoperative VCUG on indication only; follow renal status until after puberty
ModerateSymptomatic before toilet training; high grade, abnormal kidneysCAP. Consider intervention for breakthrough infection or persistent refluxRe-evaluate at 12–24 months
ModerateAsymptomatic (prenatal hydronephrosis or sibling); high grade, abnormal kidneysCAP. Consider intervention for breakthrough infection or persistent refluxRe-evaluate at 12–24 months
ModerateSymptomatic after toilet training; high grade, normal kidneys, LUTDTreat LUTD, with CAP. Consider intervention if LUTD persistsRe-evaluate after successful urotherapy
ModerateSymptomatic after toilet training; low grade, abnormal kidneysControversial. Endoscopic treatment is an optionFollow renal status until after puberty
ModerateSymptomatic; normal kidneys, low grade, LUTDTreat LUTD; CAP optionalFollow UTI and LUTD
LowSymptomatic; normal kidneys, low grade, no LUTDNo treatment or CAPFollow UTI
LowAsymptomatic; normal kidneys, low gradeNo treatment (CAP possible in infants)Follow UTI

Two keys unlock the table. The core of the high-risk group is high-grade reflux found through symptoms after toilet training, combined with abnormal kidneys. The same high grade before toilet training is moderate risk, because spontaneous resolution of high-grade reflux is more common in infants. And when LUTD is present, its treatment comes first in every risk group; in the corresponding high-risk group without LUTD, intervention is considered from the outset.

Three situations taken from the EAU/ESPU risk table. All share symptomatic grade IV–V reflux with abnormal kidneys. Before toilet training the child is moderate risk and starts CAP; after toilet training with LUTD the child is high risk and receives LUTD treatment with CAP; after toilet training without LUTD the child is high risk and intervention is considered
The same high-grade reflux leads to different first steps. Three examples taken from the risk table; this is not a scored prognostic model.

The AUA divides by age instead of by table. Under one year it recommends antibiotic prophylaxis for a history of febrile UTI or grade III–V reflux; at one year or older it recommends prophylaxis when BBD is present, for as long as the BBD exists and is being treated (Recommendation). When BBD, recurrent febrile UTI and renal cortical abnormality are all absent, prophylaxis and observation are both options (Option); if any one of them is present, observation is not recommended. Treatment in the presence of recurrent infection or cortical abnormality is decided individually under the breakthrough-infection section. The AAP 2026 guideline draws explicit boundaries for primary care. Low risk is grade I–II without BBD; high risk is any of grade IV–V, intrarenal reflux, renal scarring, structural or cortical abnormality, recurrent pyelonephritis, bacteraemia leading to intensive-care admission, or BBD. Grade III is set apart as uncertain. Note that BBD in this risk classification excludes functional constipation, so it cannot be compared directly with BBD as defined by the other guidelines.

The three classifications share their axes: grade, bladder and bowel function, and renal abnormality. What they decide differs. In EAU/ESPU the classification sets the intensity of the whole management plan; in the AUA it mainly decides whether to recommend prophylaxis; in the AAP it determines what happens in primary care and when to refer to a specialist.

3. Has the stratification been validated?

The studies that have tested the EAU/ESPU risk groups against real outcomes are, as far as I could find, retrospective series from a single country. One study of 157 children, counting a new infection or new scar as treatment failure, concluded that the low-risk group had been overtreated8; another, comparing 334 renal units before and after the risk groups were introduced, found fewer primary operations in the moderate- and high-risk groups without any change in early clinical success9. A multicentre study of 1,345 patients (1,988 renal units) at nine institutions also exists, but it examined practice patterns in surgically treated patients and reported that practice in the low- and moderate-risk groups still did not follow the guideline10. More broadly, a 2026 review found that of 17 reflux prediction tools published over 39 years, only five had been externally validated and none was suitable for general use11.

The risk table is best read as a consensus framework that organises judgement where evidence is thin, not as a prognostic model that has passed adequate external validation. Read that way, its usefulness becomes clear: it tells you what to do first for this child, but not whether this child will do badly.

4. When do reflux follow-up and kidney follow-up end?

Follow-up should be split in two. Reflux follow-up moves, once resolution is confirmed, to considering an end to routine reflux imaging (a febrile infection after resolution prompts re-evaluation for BBD and recurrent reflux). Kidney follow-up runs much longer, depending on any remaining renal abnormality.

ItemAUA (2010/2017)EAU/ESPU (2026)
Annually while reflux persistsBlood pressure, height, weight; urinalysis for protein and bacteriuria (Recommendation)UTI, LUTD and renal status (risk table)
UltrasoundEvery 12 months for renal growth and scarring (Recommendation)Part of routine imaging follow-up
Follow-up cystographyEvery 12–24 months, longer if resolution is less likely (Recommendation). Option under observation. One normal study can establish resolution (Option)Full re-evaluation at 6 or 12–24 months by risk group. In the relevant high-risk surgical group of the EAU table, postoperative VCUG on indication only
DMSAFor abnormal ultrasound, breakthrough infection or grade III–V reflux, or raised creatinine (Recommendation). Checking for new scars after febrile UTI is an OptionBaseline at diagnosis, later comparison
After resolutionAnnual evaluation through adolescence if either kidney is abnormal (Recommendation); Option if both are normal. Evaluate for BBD and recurrent reflux if febrile UTI occursChildren with renal abnormalities: follow renal status until after puberty

The UTI guidelines approach follow-up differently. NICE advises no long-term follow-up for a minor unilateral parenchymal defect in the absence of recurrent infection, family history or risk factors for hypertension, with bilateral abnormality, impaired renal function, hypertension or proteinuria managed by a paediatric nephrologist. This contrasts with the AUA's annual evaluation through adolescence for any abnormality, even in one kidney. EAU/ESPU adds that there is no evidence that small scars, even bilateral ones, cause hypertension or renal failure, and that problems in pregnancy are possible with severe bilateral damage. That should not be read as meaning other patients carry no risk; it is better treated as a matter for individual assessment according to the extent of scarring, renal function, blood pressure and proteinuria.

Conceptual diagram of reflux follow-up and kidney follow-up as two timelines. Reflux follow-up runs from diagnosis to confirmed resolution, after which an end to routine reflux imaging is considered, with BBD and recurrent reflux re-evaluated if a febrile UTI occurs. Kidney follow-up continues beyond adolescence if a renal abnormality remains
The reflux may resolve while the reasons for follow-up remain. The timeline is conceptual and does not indicate test intervals.

So it is not accurate to say that "the guidelines do not say when to stop." Reflux follow-up has an end point, and the duration of kidney follow-up is set by whether an abnormality exists. The gap lies in between: neither guideline sets an individual schedule for how many more cystograms to perform, nor says who should look after people with renal abnormalities beyond adolescence, and how.

Closing Part 2

Whether the boundaries of the risk groups predict the actual course, how many times cystography should be repeated, and who should look after renal abnormalities beyond adolescence are gaps left open by both guidelines. If the question of Part 1 was "is finding reflux the same as changing the prognosis?", Part 2 turns it into this: sorting children into risk groups and that sorting predicting outcomes are two further, separate questions. Part 3 turns to the decision in which the classification is used most directly: antibiotic prophylaxis.

A note on currency

Guideline texts checked on 19 October 2026.

References

Sang Woon Kim, MD (김상운)
Pediatric Urologist · Visiting Scholar, Toronto, Canada
This content is provided for academic reference. Individual patient care decisions should be made by the treating clinician.