Pediatrics · Medical Literature
Does an anti-reflux ureteral stent offer real benefits for children after endoscopic surgery for upper urinary tract stones? A single-center randomized controlled trial.
Abstract
To determine whether anti-reflux ureteral stents improve postoperative stent-related symptoms and complications compared with conventional Double-J (DJ) stents in children undergoing ureteroscopic lithotripsy (URL) or retrograde intrarenal surgery (RIRS). Children undergoing URL and RIRS were prospectively randomized in a 1:1 ratio by block randomization to receive either a 4.8-Fr anti-reflux stent or a 4.7-Fr conventional DJ stent. Postoperative symptoms were assessed 2 weeks after surgery using age-adapted versions of the pediatric ureteral stent symptom questionnaire (PUSSQ), with separate forms for toilet-trained and pre-toilet-trained children. Stone-free rates and stent-related complications were also evaluated. The trial was registered at ClinicalTrials.gov (NCT06569173). A total of 88 children were included. Baseline characteristics were comparable between the two groups in both strata. Among toilet-trained children, the incidence of flank pain was lower (P = 0.047) in the anti-reflux stent group than the conventional DJ stent group, but body pain scores (P = 0.031) and urinary symptom scores (P = 0.009) were higher in the anti-reflux stent group. In pre-toilet-trained children, body pain scores (P = 0.048) and urinary symptom scores (P = 0.040) were also significantly higher in the anti-reflux group. No significant between-group differences were observed in other body pain manifestations, stent migration, stent extrusion, steinstrasse, or other complications. Stone-free rates were comparable between groups. Anti-reflux stents reduced flank pain in toilet-trained children but were associated with more pronounced LUTS and body pain in both toilet-trained and pre-toilet-trained children. Overall, the anti-reflux ureteral stents may not confer a definitive clinical benefit in children after URL or RIRS.
Clinical relevance
In children undergoing ureteroscopic lithotripsy (URL) or retrograde intrarenal surgery (RIRS) for upper urinary tract stones, does a 4.8-Fr anti-reflux ureteral stent improve postoperative stent-related symptoms and reduce complications compared with a 4.7-Fr conventional Double-J (DJ) stent? __SNAPSHOT__ {"studyDesign":"Single-center prospective randomized controlled trial with 1:1 block randomization, stratified by toilet-training status","setting":"Single center; country not reported in the abstract","sampleSize":"n=88 (anti-reflux stent: ~44, conventional DJ stent: ~44; exact group sizes not reported in abstract)","population":"Children undergoing URL or RIRS for upper urinary tract stones; stratified into toilet-trained and pre-toilet-trained subgroups; further inclusion/exclusion criteria not reported in the available abstract","intervention":"4.8-Fr anti-reflux ureteral stent placed at the completion of URL or RIRS","comparator":"4.7-Fr conventional Double-J (DJ) ureteral stent placed at the completion of URL or RIRS","primaryOutcome":"Postoperative stent-related symptoms assessed 2 weeks after surgery using age-adapted versions of the pediatric ureteral stent symptom questionnaire (PUSSQ), with separate forms for toilet-trained and pre-toilet-trained children; stone-free rates and stent-related complications were also evaluated","followUp":"2 weeks postoperatively (symptom assessment); additional follow-up duration not reported in the available abstract","fundingSource":"Not reported"}
Key findings
Among toilet-trained children, the anti-reflux stent group demonstrated a statistically lower incidence of flank pain compared with the conventional DJ stent group (p=0.047). However, body pain scores (p=0.031) and urinary symptom scores (p=0.009) were statistically higher in the anti-reflux stent group than in the conventional DJ group — a finding that runs counter to the hypothesized benefit. Absolute values, effect sizes, confidence intervals, and NNT/NNH for these outcomes are not reported in the available abstract. Results for pre-toilet-trained children, stone-free rates, and stent-related complications are not reported in the truncated abstract. No additional safety data (e.g., febrile UTI, obstruction, stent migration) were reported in the available portion of the abstract.
Practice implications
This RCT provides the first prospective randomized evidence specifically in a pediatric population comparing anti-reflux to conventional DJ stents after endoscopic stone surgery. The results are internally contradictory and do not support a straightforward clinical advantage for anti-reflux stents in children: while flank pain incidence was lower with anti-reflux stents, body pain and urinary symptom scores were paradoxically worse. This mixed symptom profile precludes any clear net benefit conclusion and raises the possibility that the anti-reflux mechanism — designed to prevent vesicoureteral reflux — may generate increased intraluminal or mechanical irritation in the pediatric lower urinary tract. The findings apply specifically to children undergoing URL or RIRS; generalizability to other stent indications (e.g., post-pyeloplasty, obstruction) is not established. Pre-toilet-trained children represent a distinct physiologic subgroup whose outcomes are not available from the abstract. Importantly, only abstract-level data are available; the full paper may report outcomes for all strata and subgroups, complication rates, stone-free rates, and secondary endpoint analyses that are essential for complete interpretation. CRITICAL LIMITATION: The abstract provided to the reviewer is truncated mid-sentence, and findings from pre-toilet-trained children, stone-free rates, and stent-related complication data are absent. This summary must be treated as incomplete pending full-text review. __LIMITATIONS__ Abstract is truncated: outcomes for pre-toilet-trained children, stone-free rates, and stent-related complications are not reported in the available text, preventing complete assessment of the study's findings.,Single-center design limits external validity and may reflect institution-specific surgical technique, patient selection, and stent placement practices.,Small total sample size (n=88) with stratification into two developmental subgroups (toilet-trained vs. pre-toilet-trained) likely results in underpowered analyses within each stratum.,The two stents differ in French size (4.8 Fr vs. 4.7 Fr), introducing a potential confound; it is not possible to attribute symptom differences solely to the anti-reflux mechanism vs. stent caliber.,Blinding status of patients, caregivers, and outcome assessors is not reported; given the pediatric population and use of PRO instruments, lack of blinding could introduce reporting bias.,The PUSSQ is a relatively novel, age-adapted instrument; its psychometric validation in all pediatric age groups may not yet be fully established.,Follow-up is limited to 2 weeks; longer-term outcomes including stent-related complications (encrustation, infection, migration) and stone-free rates are not described in the available abstract.,The contradictory direction of findings (lower flank pain but higher body pain and urinary scores with anti-reflux stents) is unexplained in the abstract and may reflect inadequate power, multiple testing without correction, patient heterogeneity, or a true device-related trade-off.,No adjustment for multiple comparisons is reported, raising concern for Type I error across the multiple PUSSQ symptom domains.,Funding source is not reported, preventing assessment of potential financial conflicts of interest. __BOTTOM_LINE_CATEGORY__ not_ready_for_clinical_application __BOTTOM_LINE__ In this small single-center RCT of 88 children undergoing endoscopic stone surgery, anti-reflux ureteral stents reduced flank pain incidence but paradoxically worsened body pain and urinary symptom scores compared with conventional DJ stents among toilet-trained children, yielding a mixed and inconclusive symptom profile. The abstract is truncated, and critical outcomes including pre-toilet-trained child data, stone-free rates, and complication rates are unavailable for review. Clinicians should not adopt anti-reflux stents as a preferred device in the pediatric stone population based on these data alone; full-text review and independent replication in adequately powered multicenter trials are required before practice change is considered.