Efficacy and Safety of Percutaneous Nephrolithotomy in Children with Previous Renal Stone Operations

Outcomes and complications of percutaneous nephrolithotomy as primary versus secondary procedure for kidney stones: a prospective cohort study

Introduction

Currently, percutaneous nephrolithotomy (PCNL) is the gold standard of treatment for large renal stones. The high prevalence of urolithiasis is associated with a high recurrence rate increasing the risk of re-intervention. This study aimed to compare the effectiveness and complications of PCNL among patients with previous therapeutic interventions for renal stones.

Methods

Between August 2018 and September 2023, 245 patients were prospectively enrolled in this study and who underwent PCNL for renal stones at our institution. We compared patients who had no previous renal surgery (group 1: n=171) with those who had a history of open renal surgery (group 2: n=45) or previous PCNL on the ipsilateral kidney (group 3: n=31). All patients underwent surgery in the Galdakao-modified Valdivia position. Data on stone characteristics and perioperative and postoperative parameters were collected. Technical features, success rates and morbidity were analyzed and compared between the groups.

Results

The fluoroscopy time was significantly longer in the group of patients with previous open surgery than in groups 1 and 3 (161.47±52.44, 223.05±33.29, 172.27±30.51 sec, P<0.001). Similarly, the operative time was longer in group 2 (138.20±38.86 min, P<0.001). The immediate stone-free rates in groups 1, 2, and 3 were 74.8%, 72.1%, and 77.4%, respectively (P=0.945). At 1-month, these rates increased to 98.8%, 96.2% and 96.8%, respectively (P=0.857). No difference was detected between the groups in terms of complication rate. The average Hb variation was 1.08±0.82, 1.34±1.01 and 0.94±0.69 g/dl for groups 1, 2 and 3, respectively(P=0.082). Hospital stay was longer in group 2 than in groups 1 and 3 (2.17±1.03, 2.53±1.22, 1.88±1.00 days, P=0.07), respectively.

Conclusion

PCNL in patients with a history of renal surgery was associated with longer fluoroscopy and operative time. However, the success and morbidity rates as a secondary procedure were similar to those of PCNL in patients with no previous intervention.

Does Previous Open Stone Surgery Affect the Outcome of Shock Wave Lithotripsy Treatment in Children?

INTRODUCTION

The aim of the study was to evaluate the efficiency of shock wave lithotripsy (SWL) in children who previously underwent ipsilateral open renal stone surgery (ORSS).

METHODS

A total of 315 renal units (RUs) with renal stones underwent SWL treatment in our department over a period of 18 years. A total of 274 RUs (87%) with no history of ORSS were categorized as group 1 and 41 RUs (13%) with a history of ORSS were categorized as group 2. The characteristics of the patients and renal stones, as well as the treatment modalities, were reviewed retrospectively, and the results were compared in terms of the rates of stone-free patients and complications.

RESULTS

The stone-free rates were statistically lower in patients with an existing history of ORSS (p = 0.002), especially for stones located at the lower calyx (p = 0.006). However, there were no differences between groups in the rate of complications (p = 0.75). History of ipsilateral ORSS, age, and stone burden were independent risk factors that predicted a stone-free status in the regression analysis (p = 0.016, p = 0.045, and p = 0.001, respectively).

CONCLUSION

The overall stone-free rate after SWL was found to be significantly lower in children with a history of ORSS than in those without, and this finding was significantly prominent for lower calyx stones. In spite of the possible difficulties in achieving surgical access due to anatomical changes in retrograde intrarenal surgery or mini-/micro-percutaneous nephrolithotomy, we believe that these techniques might be good alternatives for SWL in future cases.

Ultrasound-Guided Minimally Invasive Percutaneous Nephrolithotomy is Effective in the Management of Pediatric Upper Ureteral and Renal Stones

Aim: To evaluate the outcome of ultrasound (US)-guided minimally invasive percutaneous nephrolithotomy (MPCNL) in the management of upper ureteral and renal stones in pediatric patients.Methods: We collected data of 112 pediatric patients who were admitted to the xxxx between March 2006 and December 2016 and treated by US-guided MPCNL. Our cohort included upper ureter stones (n = 11), single kidney stones (n = 46), multiple kidney stones (n = 56), and staghorn kidney stones (n = 12).Results: Patients were between 0.5 and 13 years old with stone sizes from 10 to 50 mm. Operation duration ranged from 15 to 195 minutes. On average, the nephrostomy tube could be removed after 3.9 days and patients were discharged after 6.5 days. We found that hemoglobin concentration decreased in 34 patients after surgery by 1 to 37.8 g/L. Using US-guided MPCNL, the initial stone-free rate (SFR) was 86.4% and resulted in a final SFR of 95.2%. However, postoperative complications occurred in 18 patients including > 38.5 °C fever in 17 cases and reactive pleural effusion in one case. Blood transfusion was not required in all cases and no sepsis, kidney loss, ureteral stricture, and adjacent organ injury were observed. Follow-up after an average of 8.5 months showed normal renal function without hydronephrosis. However, recurrence of stones > 4 mm was found in 11 patients.Conclusions: US-guided MPCNL showed an excellent SFR and low complication rate in the management of pediatric patients with upper ureteral and renal stones.

Efficacy and Safety of Supracostal Access for Mini Percutaneous Nephrolithotomy in Pediatric Patients

OBJECTIVE

To evaluate the efficacy and safety of supracostal percutaneous nephrolithotomy (PCNL) through the 11th intercostal space and compare it with subcostal PCNL in children with renal calculi.

MATERIALS AND METHODS

Children with renal calculi who underwent PCNL between January 2010 and December 2017 were divided into 2 groups: supracostal PCNL (group 1) and subcostal PCNL (group 2). Stone location, stone burden, location of the access points, operative time, postoperative visual pain score, success rate, hospital stay, and complications according to the modified Clavien classification were compared. Comparison of medians was done using Mann Whitney U test and the means were compared using t test.

RESULTS

Group 1 had 50 patients while group 2 had 60 patients. The stone-free rate was 84.0% and 85.0% in groups 1 and 2, respectively after 1 session of PCNL (P = .885). After auxiliary procedures, it increased to 96.0% and 96.6%, respectively (P = .852). The mean fall in hematocrit was 0.9% in group 1 and 1.5% in group 2 (P = .11) whereas the median pain score was 4 in group 1 and 3 in group 2 (P = .37). In all, 54 complications were recorded the commonest among which were grade I (81.5%). Twenty-nine complications were observed in group 1 while 25 complications were observed in group 2 (P = .088). One patient developed nephropleural fistula while another patient developed hydropneumothorax. Both belonged to group 1.

CONCLUSION

Supracostal access for PCNL is an effective and safe alternative to subcostal access for children with renal calculi in terms of stone-free rate and complications.

Prediction of Pediatric Percutaneous Nephrolithotomy Outcomes Using Contemporary Scoring Systems

PURPOSE

We evaluate the applicability of contemporary percutaneous nephrolithotomy scoring systems in pediatric patients and compare their predictive power regarding postoperative outcomes.

MATERIALS AND METHODS

We retrospectively analyzed the records of 125 children who were diagnosed with renal calculi and underwent percutaneous nephrolithotomy between March 2011 and April 2016. Predictive scores, which consisted of Guy's Stone Score, S.T.O.N.E. (stone size, tract length, obstruction, number of involved calyces and essence/stone density) nephrolithometry and CROES (Clinical Research Office of the Endourological Society) nomogram, were calculated for all patients included in the study. Patient demographics, stone-free rate and complications were all analyzed and are reported.

RESULTS

Median Guy's Stone Score was 2 (IQR 2 to 3) in patients with residual stones (group 1) and 2 (1 to 2) in those who were stone-free (group 2). Median respective CROES nomogram scores were 215 (IQR 210 to 235) and 257 (240 to 264), and S.T.O.N.E. nephrolithometry scores were 8 (7 to 9) and 5 (5 to 6, all p <0.0001). S.T.O.N.E. score demonstrated the greatest accuracy in predicting stone-free rate. Guy's Stone Score was significantly correlated with complications but the CROES and S.T.O.N.E. scores were not significantly correlated with complications.

CONCLUSIONS

The scoring systems analyzed could be used to predict success of percutaneous nephrolithotomy in the pediatric setting. However, further studies are needed to formulate modifications for use in children. The main variables in the scoring systems, ie stone burden, tract length and case volume, were measured using records from adult patients. Besides these variables, the relatively small pelvicalyceal system and higher incidence of anatomical malformations in children could potentially affect percutaneous nephrolithotomy outcomes.

Impact of previous open renal surgery on the outcomes of subsequent percutaneous nephrolithotomy: a meta-analysis

OBJECTIVE

The aim of this study was to systematically compare the perioperative outcomes of percutaneous nephrolithotomy in patients with or without previous ipsilateral open renal surgery (POS).

DESIGN

Systematic searches of the PubMed, Web of Science and Cochrane Library databases were used to identify relevant studies, and, following literature screening and data extraction, a meta-analysis was performed.

RESULTS

17 retrospective cohort studies involving 4833 procedures (4784 patients) were included. No statistically significant differences were observed between patients with or without POS in terms of supracostal access; single/multiple tracts; metal dilator need; time required to access the collecting system; fluoroscopic duration; demand for analgesics; hospital stay; final stone-free rate; and risk of developing certain complications (eg, fever, haemorrhage, haemo/hydro/pneumothorax, blood transfusion, urinary tract infection and sepsis) as well as regarding the risk of total complications. Patients with POS, however, had a greater drop in haemoglobin (weighted mean difference (WMD), 1.78 g/L; 95% CI 1.09 to 2.47; p<0.00001) and higher risk of bleeding that required angiographic embolisation (relative risk (RR), 3.73; 95% CI 1.36 to 10.21; p=0.01). In addition, patients with POS also had a lower initial stone-free rate (RR, 0.96; 95% CI 0.92 to 0.99; p=0.007) and more secondary treatment (RR, 1.61; 95% CI 1.09 to 2.37; p=0.02). Sensitivity analysis produced comparable results except for differences in operative time and initial stone-free rate, which did, however, prove to be statistically insignificant (p=0.16 and 0.69, respectively).

CONCLUSIONS

Current evidence suggests that percutaneous nephrolithotomy in patients with POS is associated with a significantly greater drop in haemoglobin, higher risk of requiring angiographic embolisation and auxiliary procedures, potentially longer operative time, and lower initial stone-free rate than percutaneous nephrolithotomy in patients without POS.