Outcomes and considerations for retrograde intrarenal surgery (RIRS) in the setting of multiple and large renal stones (>15 mm) in children: Findings from multicentre and real-world setting.

Purpose: The aim of this study is to evaluate the outcomes of retrograde intra renal surgery (RIRS) in the setting of large or multiple stones in children (<18 years). Materials and Methods: Retrospective analysis was performed of paediatric RIRS cases at nine centres worldwide over a 6-year period. Patients were divided into two groups: Group 1 had a single stone <15 mm. Group 2 had either multiple stones, maximum stone diameter of >15 mm, or both. Outcomes included stone free rate (SFR) and complications within 30 days. Results: In total, 344 patients were included with 197 and 147 in Groups 1 and 2, respectively. Ureteric access sheaths were more frequently used in Group 2 (39.5% vs. 56.8%, p = 0.021). The operation time was significantly longer in Group 2 (p < 0.001). SFR after a single procedure was 84.7% in Group 1 and 63.7% in Group 2. Overall complication rates in Groups 1 and 2 were 7.6% and 33.3%, respectively. The most frequently reported complication in both groups was post-operative fever (4.4% vs. 14%, p = 0.004). The rate of Clavien I/II complications in groups 1 and 2 was 6% and 25.1%, respectively (p < 0.05). The rate of Clavien ≥ III complications in groups 1 and 2 was 1.6% and 8.1%, respectively (p < 0.05). On multivariate analysis, total operation time, stone size and multiplicity were significant predictors of residual fragments. Conclusions: RIRS can be performed in paediatric cases with large and multiple stone burdens, but the complication rate is significantly higher when compared to smaller stones.

First worldwide report on safety and efficacy of using small 7.5 Fr scope for pediatric ureteroscopy: prospective pilot series from Europe.

Introduction: Although pediatric urolithiasis remains relatively uncommon, its global prevalence is on the rise. Technological advances have led to miniaturization of instruments especially in the form of single use scopes. As the evidence on the use of small single use ureteroscopes in children is scarce, we have conducted a pilot two-center study to analyze the outcomes of pediatric patients treated with the Pusen 7.5 Fr single use scopes at our institutions. Material and methods: This study included consecutive pediatric patients with urinary stones treated with the small Pusen 7.5 Fr single use ureteroscope. The study was conducted at two large European tertiary endourology centers that specialize in pediatric kidney stone management. Patient data and outcomes were prospectively collected, and analysis was performed regarding patient demographics, stone parameters, as well as stone free rate (SFR), operating time, and complications. Results: In this pilot study, 26 patients were included with a median age of 12 years (7.0-16.0) and a male to female ratio of 14:12. The mean cumulative stone size was 15.15 mm (SD ±11.1) and multiple stones were present in 9 (34.6%) patients. Pre-operative stent, access sheath and post-operative stent usage was done in 12 (46.2%), 23 (88.5%) and 13 (50%) patients respectively. The median operative time was 47 minutes (IQR: 40.0-63.8). Following the initial procedure 24 (92.3%) patients were stone free, while no intra or postoperative complications were observed. Conclusions: Our study demonstrates that the use of the small 7.5 single use ureteroscope is safe and efficient for the treatment of urinary stones in pediatric patients with high stone-free rates and no complications noted in our series. While this might become a standard of care in future, to confirm and validate our findings further studies with larger cohorts are warranted.

Comparison and Evaluation of Outcomes of Ureteroscopy and Stone Laser Fragmentation in Extremes of Age Groups (≤10 Years and ≥80 Years of Age): A Retrospective Comparative Analysis of over 15 Years from 2 Tertiary European Centres.

AIM: To assess and compare the outcomes associated with ureteroscopy and laser fragmentation (URSL) for extremes of age group (≤10 and ≥80 years). METHODS: Retrospective consecutive data were collected from two European centres for all paediatric patients ≤10 undergoing URSL over a 15-year period (group 1). It was compared to consecutive data for all patients ≥80 years (group 2). Data were collected for patient demographics, stone characteristics, operative details, and clinical outcomes. RESULTS: A total of 168 patients had 201 URSL procedures during this time (74 and 94 patients in groups 1 and 2 respectively). The mean age and stone sizes were 6.1 years and 85 years, and 9.7 mm and 13 mm for groups 1 and 2 respectively. While the SFR was slightly higher in group 2 (92.5% versus 87.8%, p = 0.301), post-operative stent rate was also significantly higher in the geriatric population (75.9% versus 41.2%, p = 0.0001). There was also no significant difference in pre-operative stenting (p = 0.886), ureteric access sheath use (UAS) (p = 0.220) and post-operative complications. Group 1 had an intervention rate of 1.3/patient as compared to 1.1/patient in group 2. The overall complications were 7.2% and 15.3% in groups 1 and 2 respectively (0.069), with 1 Clavien IV complication related to post-operative sepsis and brief ICU admission in group 2. CONCLUSION: The paediatric population had a marginally higher incidence of repeat procedure, but the overall SFR and complications were similar, and post-operative stent insertion rates were much better compared to geriatric patients. URSL is a safe procedure in the extremes of age groups with no difference in the overall outcomes between the two groups.

Role of Preoperative Ureteral Stent on Outcomes of Retrograde Intra-Renal Surgery (RIRS) in Children. Results From a Comparative, Large, Multicenter Series.

OBJECTIVE: To assess outcomes of pre-stenting versus non-pre-stenting in children undergoing retrograde intrarenal surgery (RIRS) for intrarenal stones. METHODS: Children/adolescent with kidney stones undergoing RIRS in 9 centers between 2015 and 2020 were retrospectively reviewed. EXCLUSION CRITERIA: ureteral lithotripsy, bilateral procedures. Stone-free status was evaluated at 3-month and defined as a single residual fragment (RF) ≤2 mm/absence of multiple fragments. Patients were divided into two groups (Group 1 no-prestenting; Group 2 prestenting). Student's, Chi-square and Fisher's exact test was used to assess difference between groups. Univariable and multivariable logistic regression analysis were performed to predict RF. Statistical significance: P-value <0.05. RESULTS: Three hundred eighty-nine children/adolescents were included (192 patients in Group 1). Prestented patients were younger compared with non-prestented (mean age 8.30 ± 4.93 vs 10.43 ± 4.30 years, P < 0.001). There were no differences in stone characteristics (number, size, locations). Lasing and total surgical time were similar. Urinary tract infections were more prevalent in Group 2 (10.7%) compared to Group 1 (3.7%, P = 0.016). Sepsis occurred in 2.1% of patients in Group 2 and no patient in Group 1 (P = 0.146). 30.7% patients in Group 1 and 26.4% in Group 2 had RF (P = 0.322). In univariate logistic regression analysis, stone size was associated with RF (OR 1.12 95%CI 1.06-1.18, P < 0.001), whereas Thulium fiber laser with a lower incidence (OR 0.24 95%CI 0.06-0.69, p=0.020). Multivariate logistic regression analysis showed that stone size was associated with RF (OR 1.20 95%CI 1.08-1.36, P = 0.001). CONCLUSIONS: RIRS showed similar stone-free rate in pre and non-prestented children/adolescents, although prestented patients were younger. A higher risk of post-operative infections was reported in prestented patients.

Multicenter comparative study of open, laparoscopic, and robotic pyeloplasty in the pediatric population for the treatment of ureteropelvic junction obstruction (UPJO)

ABSTRACT Introduction: Dismembered open pyeloplasty described by Anderson and Hynes is the "gold standard" for the treatment of ureteropelvic junction obstruction. The aim of our study was to compare the results of open (OP) vs laparoscopic (LP) vs robotic (RALP) pyeloplasty. Material and Methods: A multicenter prospective review was conducted of pyeloplasty surgeries performed at five high-volume centers between 2014 and 2018. Demographic data, history of prenatal hydronephrosis, access type, MAG3 renogram and differential renal function, surgery time, length of hospital stay, and complication rate (Clavien-Dindo) were recorded. Access type was compared using the Kruskal-Wallis, Chi-square, or Fisher's exact tests. Results: A total of 322 patients were included: 62 OP, 86 LP, and 174 RALP. The mean age was 8.13 (r: 1-16) years, with a statistically significant lower age (mean 5 years) in OP (p < 0.001). There were no significant differences in the distribution of the side affected. Operative time was 110.5 min for OP, 140 min for LP, and 179 min for RALP (p < 0.0001). Hospital stay was significantly shorter in the RALP group than in the other groups (p < 0.0001). There were no differences in postoperative complications and reoperations between the three groups. Conclusions: Minimally invasive surgery for the management of UPJO in children is gaining more acceptance, even in patients younger than 1-year-old. Operative time continues to be significantly shorter in OP than in LP and RALP. Hospital stay was shorter in RALP compared to the other techniques. No differences were found in complication rates, type of complications, and reoperation rate.

Multicenter comparative study of open, laparoscopic, and robotic pyeloplasty in the pediatric population for the treatment of ureteropelvic junction obstruction (UPJO).

INTRODUCTION: Dismembered open pyeloplasty described by Anderson and Hynes is the "gold standard" for the treatment of ureteropelvic junction obstruction. The aim of our study was to compare the results of open (OP) vs laparoscopic (LP) vs robotic (RALP) pyeloplasty. MATERIAL AND METHODS: A multicenter prospective review was conducted of pyeloplasty surgeries performed at five high-volume centers between 2014 and 2018. Demographic data, history of prenatal hydronephrosis, access type, MAG3 renogram and differential renal function, surgery time, length of hospital stay, and complication rate (Clavien-Dindo) were recorded. Access type was compared using the Kruskal-Wallis, Chi-square, or Fisher's exact tests. RESULTS: A total of 322 patients were included: 62 OP, 86 LP, and 174 RALP. The mean age was 8.13 (r: 1-16) years, with a statistically significant lower age (mean 5 years) in OP (p < 0.001). There were no significant differences in the distribution of the side affected. Operative time was 110.5 min for OP, 140 min for LP, and 179 min for RALP (p < 0.0001). Hospital stay was significantly shorter in the RALP group than in the other groups (p < 0.0001). There were no differences in postoperative complications and reoperations between the three groups. CONCLUSIONS: Minimally invasive surgery for the management of UPJO in children is gaining more acceptance, even in patients younger than 1-year-old. Operative time continues to be significantly shorter in OP than in LP and RALP. Hospital stay was shorter in RALP compared to the other techniques. No differences were found in complication rates, type of complications, and reoperation rate.

Outcomes and lessons learnt from practice of retrograde intrarenal surgery (RIRS) in a paediatric setting of various age groups: a global study across 8 centres.

PURPOSE: To analyse and report the practice, outcomes and lessons learnt from a global series of retrograde intrarenal surgery (RIRS) in a paediatric multicentre series. METHODS: A retrospective review of anonymized pooled data gathered globally from 8 centres in paediatric patients (≤ 18 years of age) who had renal stones and underwent RIRS from 2015 to 2020 was performed. Patient demographics, perioperative parameters, stone characteristics, complications and stone-free rate (SFR; defined as endoscopically stone free and/or residual fragments < 2 mm on follow up imaging) were analysed. The cohort was stratified into 3 groups by age: < 5 years (Group A), 5-10 years (Group B) and > 10 years (Group C). Overall, post-operative complication rate was 13.7%. Chi-square comparisons were used for categorical variables; analysis of variance (ANOVA) or Kruskal-Wallis tests were used for continuous variables. RESULTS: 314 patients were analysed. The mean age was 9.54 ± 4.76 years. Groups A, B and C had 67 (21.3%), 83 (26.4%) and 164 (52.2%) patients, respectively. Mean stone size was 10.7 ± 4.62 mm. Pre-stenting was performed in 155 (49.4%) of patients, ureteral access sheaths (UAS) was used in 54.5% of patients with majority (71%) utilizing holmium laser for stone fragmentation. All complications were minor (Clavien-Dindo grade 1 and 2). SFR was 75.5%. CONCLUSIONS: RIRS is acceptable as a first-line intervention in the paediatric population with reasonable efficacy and low morbidity. Complications are slightly higher in patients < 5 years of age, which should be taken into account while counselling patients.

Is Flexible Ureteroscopy and Laser Lithotripsy the New Gold Standard for Pediatric Lower Pole Stones? Outcomes from Two Large European Tertiary Pediatric Endourology Centers.

Introduction: Although pediatric ureteroscopy has been increasingly performed, the evidence for its use in pediatric lower pole stones (LPS) is sparce. In this study we look at the effectiveness and outcomes of flexible ureteroscopy and laser lithotripsy (FURSL) in the management of LPS for a pediatric population. Materials and Methods: Data were collected from two large European tertiary endourology centers that specialize in pediatric kidney stone management. The study was registered as an audit at the respective hospitals. All data were cross-checked and analyzed using electronic operative notes, discharge records, laboratory systems, and patient correspondence. The inclusion criteria were patients ≤16 years with LPS having an FURSL procedure. Results: A total of 57 pediatric patients underwent FURSL for LPS. The mean age was 10.1 ± 4.7 years (range: 1-16.9 years) with a male-female ratio of 2:3. The mean single stone size was 9.45 ± 3.9 mm (range: 3-20 mm) and 31 (54.4%) had multiple stones. A preoperative stent was present in 18 (31.6%) patients and a postoperative stent or ureteral catheter was left behind in 32 (56.1%) patients. The initial and final stone-free rates were 82.4% and 98.2%, respectively, with 1.19 procedures per patient performed to be stone free. Although there were no intraoperative complications, there were only four (7%) minor complications (Clavien I) noted that were all simple urinary infections. No long-term complications were noted. Conclusion: Flexible ureteroscopy and lasertripsy achieve excellent outcomes for treatment of pediatric LPS. Although some patients might need a second procedure for complete stone clearance, FURSL may be considered as the first-line treatment of LPS.