Preoperative abdominal pain reflects distinct intraoperative findings but not worse outcomes of laparoscopic pyeloplasty for ureteropelvic junction obstruction in children.
TL;DR
Preoperative abdominal pain identified UPJO patients with distinct intraoperative findings-particularly pelvic wall thickening-yet ultrasonographic improvement and surgical success were comparable across presentations; a modest disadvantage for symptomatic patients cannot be excluded and should be addressed in adequately powered studies.
Abstract
Objective
To characterize macroscopic intraoperative findings associated with preoperative abdominal pain versus asymptomatic presentation in children with severe ureteropelvic junction obstruction (UPJO), and determine whether laparoscopic pyeloplasty outcomes differ between these clinically distinct phenotypes.
Methods
Retrospective cohort of 132 consecutive children with Society for Fetal Urology (SFU) grade 4 hydronephrosis who underwent laparoscopic Anderson-Hynes pyeloplasty at a tertiary pediatric center (November 2020-December 2024). Patients were stratified by documented preoperative pain (Pain Group n = 54; No Pain Group n = 78). The primary endpoint was percentage improvement in anteroposterior diameter (PI-APD); the profile of intraoperative findings was a prespecified descriptive comparison. Multivariable linear regression for PI-APD was a secondary analysis.
Results
Intraoperative findings differed markedly between groups. The Pain Group had fewer cases with no special findings (46.3% vs 76.9%, P < 0.001), greater intraoperatively assessed pelvic wall thickening (38.9% vs 19.2%, P = 0.017; subjective surgeon assessment), more ureteral polyp (9.3% vs 1.3%, P = 0.042), and a non-significant trend toward crossing vessels (7.4% vs 1.3%). Despite these differences, ultrasonographic improvement and surgical success did not differ significantly: PI-APD 59.8% vs 64.8% (P = 0.239) and comparable absolute parenchymal recovery (ΔPT 2.69 vs 2.66 mm, P = 0.941; proportional recovery reflected expected age-related development). On multivariable regression, baseline APD (P < 0.001) and pelvic wall thickening (B = 10.42, P = 0.016) were independent positive predictors of PI-APD; pain itself was not statistically significant (B = -9.37, P = 0.081).
Conclusion
In this single-center cohort, preoperative abdominal pain identified UPJO patients with distinct intraoperative findings-particularly pelvic wall thickening-yet ultrasonographic improvement and surgical success were comparable across presentations; a modest disadvantage for symptomatic patients cannot be excluded and should be addressed in adequately powered studies. These hypothesis-generating findings support uniform surgical management. Functional (renographic) outcomes were not assessed and require prospective confirmation.