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Published on: July 18, 2025
Optimum duration of ureteral prestenting dwelling time in children undergoing retrograde intrarenal surgery
Ahmed Fahmy1, Waleed Dawoud1, Haytham Badawy1
1Urology Department, Alexandria University, Egypt.
Insights
For pediatric kidney stone treatment with retrograde intrarenal surgery (RIRS), a shorter ureteral stent dwelling time (two weeks) reduces infection risk without impacting stone-free rates or operative success.
Area of Science:
- Pediatric Urology
- Minimally Invasive Surgery
- Nephrolithiasis Management
Background:
- Ureteral prestenting aids retrograde intrarenal surgery (RIRS) by dilating the ureter, potentially improving outcomes.
- However, prolonged ureteral stent dwelling time is linked to increased septic complication risks.
Purpose of the Study:
- To evaluate the impact of ureteral prestenting timing on perioperative outcomes and complications in pediatric RIRS.
- To determine the optimal dwelling time for ureteral stents prior to RIRS in children.
Main Methods:
- Retrospective analysis of 60 children under 14 with upper tract stones undergoing RIRS.
- Patients were divided into two groups: two-week stent dwelling (Group 1, n=30) and four-week stent dwelling (Group 2, n=30).
- Key outcomes included ureteroscope access, operative time, stone-free rate (SFR), and complications.
Main Results:
- Successful ureteric access was achieved in all patients.
- Stone-free rates were comparable (86.6% vs. 90%, p=0.199).
- Postoperative UTI rates significantly increased with longer dwelling time (6.7% vs. 30%).
Conclusions:
- Extending ureteral stent dwelling time from two to four weeks did not improve ureteroscopic access or SFR in pediatric RIRS.
- Shorter stent dwelling times (two weeks) minimize postoperative UTI risk without compromising RIRS success.
Introduction And Objectives:
Ureteral prestenting before retrograde intrarenal surgery (RIRS) causes passive dilatation of the ureter, improves stone-free rate and is associated with shorter operative time. However, the presence of a ureteric stent may increase the risk for septic complications, which accelerates with increased dwelling time duration. The aim of the present study is to explore the impact of ureteral prestenting timing in a group of children undergoing retrograde intrarenal surgery (RIRS) on perioperative outcomes and complication rates and to define the optimum duration of prestenting dwelling time.
Patients And Methods:
A retrospective study on 60 children aged less than 14 years, presented with upper tract urinary stones, who were subdivided into two groups: Group 1 and 2, each included 30 children who had undergone RIRS after ureteric stenting for two weeks and four weeks respectively. Success of ureteroscope introduction, operative time, stone free rate (SFR), intraoperative and postoperative complications and number of retreatment procedures after definitive RIRS were recorded and compared between the two treatment groups.
Results:
Ureteric access was successfully obtained in all children in both groups. Patients in group 1 and 2 had a SFR of 86.6% and 90%, respectively (p = 0.199). The mean operative time of group 1 and 2 were 56.5 and 52.9 min (p = 0.612). Postoperative UTI rates increased with prolonged dwelling time from 6.7% in group 1 to 30% in group 2. No patient in both groups developed high grade complications.
Conclusions:
Increasing prestenting dwelling time from two to four weeks had no statistically significant effect on the successful ureteroscopic access nor the stone free rate in children undergoing RIRS. Reducing the ureteric stent dwelling time minimizes the rate of postoperative UTI without compromising the success of operative outcomes.
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