Comparing micropercutaneous nephrolithotomy and retrograde intrarenal surgery in treating 1-2 cm solitary renal stones in pediatric patients younger than 3 years

Comparative efficacy and safety between Micro-Percutaneous Nephrolithotomy (Micro-PCNL) and retrograde intrarenal surgery (RIRS) for the management of 10–20 mm kidney stones in children: A systematic review and meta-analysis

Objectives

Kidney stone in children is a recurring problem that requires multiple interventions over time. Minimally-invasive approach, such as Extracorporeal Shockwave Lithotripsy (ESWL) is recommended for moderately-sized stones. However, since ESWL is associated with multiple interventions, Micro-Percutaneous Nephrolithotomy (Micro-PCNL) and Retrograde Intrarenal Surgery (RIRS) can also be considered to treat kidney stones in pediatric patients. Both approaches have their respective advantages and disadvantages. In this study, we aimed to compare the efficacy and safety of Micro-PCNL and RIRS in pediatric patients with kidney stones.

Methods

This systematic review and meta-analysis adhered to the PRISMA guideline and Cochrane Handbook of intervention. The included studies were obtained from the PubMed and ScienceDirect databases. The protocol of this review has been registered in PROSPERO (CRD42021265894). The quality of the studies was assessed using the Newcastle-Ottawa Scale, outcomes were analyzed using STATA®16, and certainty of evidence was evaluated using GRADE.

Results

A total of 239 participants were included in this study, divided into the Micro-PCNL (n = 112) and RIRS (n = 127) procedure groups. Statistical analysis revealed a significantly lower requirement of postoperative stenting procedure in Micro-PCNL compared to RIRS (OR 0.09; 95%CI 0.02, 0.47; p < 0.01). However, no significant difference was found in stone-free rate (p = 0.86), operative time (p = 0.09), UTI incidence (p = 0.67), blood transfusion requirement (p = 0.95), and length of stay (p = 0.77).

Conclusion

Micro-PCNL is superior to RIRS in managing pediatric kidney stones,10–20 mm in size based on their comparable SFR and fewer requirements of additional stenting procedures.

•

Micro-PCNL had a comparable SFR to RIRS in managing pediatric kidney stones,10–20 mm.

•

Micro-PCNL had less requirement of stenting procedure than RIRS in managing pediatric kidney stones,10–20 mm.

•

Micro-PCNL is superior to RIRS in managing pediatric kidney stones,10–20 mm.

External validation of efficacy and reliability of different retrograde intrarenal surgery (RIRS) scoring systems for pediatric nephrolithiasis

INTRODUCTION

Retrograde Intrarenal Surgery (RIRS) is one of minimally invasive procedures for pediatric upper urinary stones. However, a RIRS predictive system for children to evaluate postoperative stone free rate (SFR) is still unavailable.

OBJECTIVE

The aim of this study is to validate the efficacy and reliability of different RIRS scoring systems for children.

STUDY DESIGN

We collected clinical data of 137 pediatric patients treated with RIRS in our center between 2014 and 2021. All the predictors were acquired by preoperative non-contrast CT or CT urography. Receiver Operative Curve (ROC) and Area Under Curve (AUC) were showed to compare the predictive power of different models.

RESULTS

A total of 162 RIRS procedures were performed for these 137 pediatric patients. Median surgical duration, irrigation volume and hospitalization were 30 (20, 40) min, 500 (300, 1000) ml and 6 (4, 7) days, respectively. Overall SFR and complication rate was 79.6% (129/162) and 29.2% (40/137), respectively. Significant difference was detected between non-stone free group and stone free group in terms of stone complexity (p < 0.001), cumulative stone sizes [2.3 (2.0, 3.5) cm vs. 1.5 (1.0, 2.0) cm, p < 0.001], RUS groups (p < 0.001), S-ReSC groups (p < 0.001) and RIRS nomogram score [10 (8, 12) vs. 23 (18, 25), p < 0.001]. Among them, RIRS nomogram presented with the maximum AUC values in comparison with the other two systems (RUS: 0.944 vs. 0.874, p = 0.001; S-ReSC: 0.944 vs. 0.808, p < 0.001).

DISCUSSION

We reported the largest sample size of pediatric patients treated with RIRS in our center. Similar with previous studies, RIRS is an efficacious and safe option for pediatric patients. RIRS nomogram showed the best predictive outcome due to the inclusion of multiple parameters, but an innovative predictive system based on pediatric clinical data is warranted in the future.

CONCLUSION

Among the three scoring systems, RIRS nomogram showed the most optimal predictive power of postoperative SFR for pediatric patients.

Comparison of mini-PCNL and retrograde intrarenal surgery in the treatment of kidney stone over 50 years old patients

Mini-Percutaneous Nephrolithotomy (M-PCNL) and Retrograde Intrarenal Surgery (RIRS) are commonly used methods in treatment of kidney stones. The aim of our study is to compare the efficacy and safety of M-PCNL and RIRS in kidney stone treatment over 50 years old patients. A total of 125 patients, 65 of whom had RIRS, and 60 of whom had M-PCNL, were included in the study. Age, gender, BMI (Body-Mass Index), ASA (American Society of Anesthesiology) scores of the patients; stone size, stone location, operation side, ESWL history, HU (Hounsfield Unit) values, hospital stay durations, SFR, complication rates according to Clavien modification system, postoperative hemoglobin loss, postoperative transfusion rates, and patients who needed a secondary operation were recorded. SFR values were calculated in the postoperative third and sixth months. The data between the two groups had similar characteristics in terms of age, gender, BMI, HU, stone size, operation side, stone location, ESWL history, operation time, postoperative transfusion rate, postoperative Clavien complications (p > 0.05). When the ASA categories were evaluated, the mean ASA scores, ASA I, and ASA II data had similar characteristics in both groups (p > 0.05). When the ASA 3 scores were evaluated, the number of ASA III patients in the RIRS group was statistically significantly higher (p < 0.05). When hospital stay duration and postoperative hemoglobin loss were examined, RIRS group was found to be advantageous (p < 0.05). Postoperative third month SFR and Postoperative sixth month values were statistically significantly higher in M-PCNL group (p < 0.05). M-PCNL and RIRS are methods that can be used safely and effectively over 50 years old patients in kidney stone surgery. M-PCNL has been found to be more advantageous in terms of SFR rates and as it requires less secondary intervention. RIRS is advantageous in terms of short hospital stay, postoperative hemoglobin loss, and applicability to patients who are not suitable for the prone position.

Can mini PCNL achieve the same results as RIRS? The initial single center experience

BACKGROUND

Urolithiasis is a prevalent disease worldwide with high recurrence rate, minimally invasive interventions have largely replaced open ones, namely PCNL and RIRS. Miniaturization, optical improvements, and modern laser types made these procedures safe and effective in the management of single renal stones.Aim of the study: Is to compare the effectiveness of mini PCNL with RIRS in the treatment of single renal stone of ≤25 mm.

PATIENTS AND METHODS

This prospective study that included 60 patients with single renal stones of ≤25 mm and were treated by either mini PCNL (group A) or RIRS (group B). The study was performed during the period from October 2020 to April 2021.

RESULTS

The mean operative time RIRS group was 43.6 ± 10.493, while for miniPCNL it was 36.6 ± 7.035 (P = 0.004). The stone free rate in RIRS and miniPCNL group was 70% and 90% respectively (P = 0.053). The need for JJ stent was higher in RIRS compared to miniPCNL group (70% vs. 40%) respectively (P = 0.02). The duration of hospital stay in miniPCNL was 38.2 h compared to 16.7 h for RIRS group (p = 0.0001). The rate of postoperative hemoglobin drop was higher in MiniPCNL compared to RIRS (P = 0.0001). There was no significant difference regarding complication rates between both groups.

CONCLUSION

Mini-PCNL FOR the treatment of renal stones sized ≤25 mm has high stone free rate, shorter operative time, less requirement for JJ stent and near similar post-operative pain and complications compared to RIRS.

External Validation of Two Predictive Models for Postoperative Fever After Retrograde Intrarenal Surgery in Pediatric Patients

Objective: The aim of this study is to validate the efficacy and reliability of two predictive models for postoperative fever after retrograde intrarenal surgery (RIRS) in pediatric patients Materials and Methods: A total of 124 children who were treated with RIRS between August 2014 and August 2020 in our center were included. All the predictors were obtained by preoperative routine examinations. Receiver operative curve (ROC) and area under curve (AUC) were showed to compare the predictive power of the two models. Results: One hundred twenty-four children included of 94 boys and 30 girls, with median ages of 2.1 (1.3, 7.0) years and median body mass index of 17.3 (15.6, 20.6) kg/m². The total points of the two nomograms were 81.0 (67.3, 90.3) and 45.5 (20.4, 94.0). Eventually, 21 children (16.9%) suffered from postoperative fever. With the exception of C-reactive protein values (25.0 mg/L vs 5.0 mg/L, p = 0.015), irrigation volumes (800 mL vs 500 mL, p = 0.01), and total points of the two predictive models (Nomogram 1: 88.0 vs 76.0, p < 0.001; Nomogram 2: 76.0 vs 39.0, p = 0.016), there was no statistical difference detected between the fever and nonfever groups. ROCs showed that Nomogram 1 presented with better predictive accuracy and efficacy with excellent AUC values of 0.805 in comparison with Nomogram 2 (0.805 vs 0.664, p = 0.025). Conclusion: We reported a sample of 124 children undergoing RIRS with a final stone-free rate of 87.1%. Twenty-one pediatric patients (16.9%) suffered from postoperative fever. Nomogram 1 presented with better predictive power for postoperative fever after RIRS in pediatric patients.

Pediatric stone disease: Current management and future concepts

Treatment of pediatric urolithiasis consists of medical and surgical approaches. The main goal of the treatment is to prevent stone recurrence by avoiding multiple surgical interventions. In recent years, many innovations have been reported in the medical diagnostic evaluation protocol and in surgical treatment. According to recent reports, single mutations could be responsible for a larger proportion of renal stones. This etiologic feature holds the potential to change the management in stone prevention from metabolically directed therapy to more specific approaches. In addition, miniaturized instruments have been adopted in clinical practice. In recent years, minimally invasive endoscopic surgery is the treatment of choice in pediatric urolithiasis. This review aims to assess the current literature on medical and surgical treatment options for pediatric urolithiasis. We also aim to provide an overview of potential future advances.

Comparison of Efficiency and Safety of Retrograde Intrarenal Surgery and Micropercutaneous Nephrolithotomy in Pediatric Kidney Stones Smaller than 2 cm: A Prospective Cohort Study

Objective: To compare the safety and efficacy of two minimally invasive surgical techniques used for pediatric stone disease: retrograde intrarenal surgery (RIRS) and micropercutaneous nephrolithotomy (micro-PCNL). Materials and Methods: A prospective study was designed to include children aged <15 years with a single stone <20 mm. Sixty-four patients were assigned to undergo either an RIRS or a micro-PCNL (1:1 ratio). Demographic parameters, stone size, location, operative data, complications, stone-free status, and efficacy quotient were compared. Results: Due to anatomic considerations, seven patients were shifted to the micro-PCNL arm, thus resulting in 39 micro-PCNLs performed vs 25 RIRS in the end. Because of the deviation from planned surgery that was significantly higher in the RIRS group (p = 0.011), the analysis was done in a prospective cohort comparison. Stone-free rates were similar for micro-PCNL and RIRS groups (80% vs 82.2%). The operative (median 60 vs 90 minutes, p < 0.001), fluoroscopy (median 15 vs 30 seconds, p = 0.004), and lithotripsy times (median 15 vs 25 minutes, p = 0.007) were shorter in the RIRS group. However, despite the larger stone size, the efficiency quotient was significantly higher in the micro-PCNL group (82.1% vs 54.1%; p = 0.009). None of the patients experienced significant hematuria requiring blood transfusion, as well as no ureteral orifice obstructive complication was detected within the follow-up period. Conclusion: RIRS and micro-PCNL techniques in children have similar stone-free and complication rates. The operative, fluoroscopy, and lithotripsy times were shorter, deviation from the planned surgery, and the number of sessions under anesthesia was higher in the RIRS group. Despite the larger stone size, efficacy quotient was significantly higher in the micro-PCNL group.

Micro-Ureteroscopy as a Treatment of Renal Pelvis Lithiasis in Young Children

Aim: Miniaturization of endoscopic instruments has allowed to improve the efficacy of kidney stone treatment in young children. Aim of the study is to evaluate the usefulness of microureteroscopy with 4.85F sheath in the treatment of renal stones in children. M&M: We present 4 cases of microureteroscopy in 3 younger than 3 years patients with renal pelvic stones. Lithiasis was unilateral in 2 female patients and bilateral in 1 male patient. Microureteroscopy was performed using a MicroPerc set 4.85F sheath, without placing a safety guide or dilating the meatus in 3 procedures. The lithotripter system used was Ho:YAG Laser with 200-μm fiber in all cases. Results: Mean operating time was 100 ± 16 min. There were no intraoperative complications. In all procedures, complete pulverization of the lithiasis was achieved, except in the coraliform lithiasis in which 5 mm residual lithiasis remained in the lower calyx. All patients were discharged 24 h after the intervention. Conclusion: Microureteroscopy can be considered a new alternative for treatment of selected cases of renal pelvic stones in infants and children.

Role of Mini-Percutaneous Nephrolithotomy in the Management of Pediatric Stone Disease: A Systematic Review of Literature

Introduction: Kidney stone disease in the pediatric setting is rare, but the incidence is rising. Mini-percutaneous nephrolithotomy (mPCNL) is one of the newer surgical interventions to have been developed in recent decades. The aim of this study was to carry out a systematic review (SR) to formally evaluate the safety and efficacy of pediatric mPCNL, which was defined as PCNLs using tract size between 15F and 20F. Methods: An SR was carried out in accordance with Cochrane guidelines and A MeaSurement Tool to Assess systematic Reviews (AMSTAR) checklist. Original studies reporting on outcomes of mPCNL with 20 or more patients (aged ≤18 years) were included. Results: Eight studies were finally identified, which satisfied our predefined criteria. This included two randomized trials and six cohort studies. A total of 384 patients with a weighted mean age of 7.5 years (range: 0.5-18 years) and a male:female ratio of 3:2 underwent mPCNL. The weighted mean stone size was 1.2 cm (range: 0.8-3.5 cm). The weighted mean operative time and length of hospital stay were 76.8 minutes (range: 20-120 minutes) and 4.6 days (range: 1-33 days), respectively. The most common location(s) of stones were lower pole (57%) and renal pelvis (24.3%). The weighted mean initial and overall stone-free rates were 87.9% (range: 76%-97.5%) and 97% (range: 91.3%-100%), respectively. None of the cases required intraoperative conversion to standard PCNL. Complications occurred in 19% (n = 73) of patients. The weighted mean transfusion rate reported across studies was 3.3% (range: 0%-10.3%). Conclusions: mPCNL is safe and effective in the pediatric population. Further randomized studies will help determine its formal role in pediatric endourology and help guideline recommendations accordingly.

Comparison of efficacy and safety of minimally invasive procedures for 10-20 mm pediatric renal Stones-A bayesian network meta-analysis

OBJECTIVE

To assess the efficacy and safety of various minimally invasive procedures for 10-20 mm pediatric renal stones by Bayesian network meta-analysis (NWA).

METHODS

We searched clinical comparative trials published in Pubmed, Embase, Cochrane Library from inception to 12 April 2020. Two researchers evaluated the quality and extracted data individually. Data was analyzed using STATA and GEMYC R package.

RESULTS

The overall network meta-analytic outcome of stone free rate (SFR) in a single session revealed that Retrograde Intrarenal Stone Surgery (RIRS), miniaturized percutaneous nephrolithotomy (mPCNL) and PCNL showed superiority to extracorporeal shockwave lithotripsy (ESWL). Statistical significance was not detected between any intervention from our pooled network analysis of complication rate. SMP was the most likely to ranking in first place to render stone free status, and it also showed the lowest risk possibility of complications. Mini-PCNL had longer operation time and hospitalization than ESWL. The global and loop inconsistency evaluation demonstrated a rather acceptable outcome apart from the comparisons of complication rate between two randomized control studies.

DISCUSSION

Herein, the authors reviewed and explored the optimal management pattern for pediatric 10-20 mm renal stones. This NWA revealed RIRS and mPCNL could render higher SFR without increasing risk of complications compared with ESWL. Although SMP was deemed to be the best choice in our study, the limited source of study and sample size implied the results required to be further validated. In addition, there were still some problems requiring to be underlined for various surgical options.

CONCLUSIONS

ESWL was inferior to RIRS, mPCNL and PCNL for 10-20 mm pediatric renal stones, among which SMP might be the most ideal option associated with the least possibility of complications and the highest probability of stone clearance.

Bilateral simultaneous RIRS for calculus anuria in a 4 months male baby

Treatment of pediatric stone disease is a challenge, more so, in the case of infants. Infantile anuria due to calculus disease is rare, as pre-renal causes predominate. Retrograde intrarenal surgery is a less often sorted modality in infants, due to the lingering skepticism regarding handling pediatric ureters and urethra. We hereby present the first case report of bilateral simultaneous RIRS, in a 4 month old male child. With better stone free rates than ESWL and a lesser incidence of major complications, we opted for RIRS in this child, taking advantage of the pre-stented ureter.