Contemporary surgical management of pediatric urolithiasis

Comparison of two percutaneous nephrolithotomy methods for the treatment of pediatric kidney stones: mini-percutaneous nephrolithotomy and standard percutaneous nephrolithotomy

OBJECTIVE

In this study, the aim was to compare the results of mini and standard percutaneous nephrolithotomy (PCNL) for the treatment of pediatric kidney stones.

MATERIALS AND METHODS

Data for 128 patients < 18 years of age who underwent mini and standard PCNL due to pediatric kidney stones were retrospectively examined. Patients were divided into two groups: mini-PCNL (16-20 Fr) and standard PCNL (26 Fr). Surgery time, number of punctures to the pelvicalyceal system, hospital stay, postoperative hemoglobin drop, complications and stone-free status (SFR) were compared between the groups. Additional surgical intervention (double-J stent, ureterorenoscopy, secondary PCNL) performed after the surgery was recorded. The absence of residual stones or < 3 mm residual stones on kidney, ureter and bladder radiography (KUB) and ultrasonography (USG) performed in the third postoperative month were accepted as success criteria.

RESULTS

There were 32 (43.8%) patients in the mini-PCNL group and 41 (56.2%) patients in the standard PCNL group. The mean age was 9.3 ± 4.1 years in the mini-PCNL group and 10.1 ± 5.4 years in the standard PCNL group. Mean stone size in the mini-PCNL group was 2.1 ± 1.2; while for standard PCNL it was 2.3 ± 1.4. The mean surgery time was statistically significantly higher in the mini-PCNL group (p = 0.005). There was no difference between the groups in terms of intraoperative double J stent use, postoperative complications and SFR. A double J stent was inserted in two patients in the mini-PCNL group and in one patient in the standard PCNL group due to urine leakage from the nephrostomy tract in the postoperative period. Although the postoperative hemoglobin drop was found to be significantly higher in standard PCNL (p = 0.001), hematuria and blood transfusion rates were low in both groups. Mean hospital stay was shorter in the mini-PCNL group compared to standard PCNL (3.6 ± 1.2 days vs. 2.5 ± 1.1; p = 0.018).

CONCLUSIONS

Although mini-PCNL has longer surgery time compared to standard PCNL, it should be preferred for the treatment of pediatric kidney stones due to advantages such as similar success and complication rates to standard PCNL, short hospital stay and less postoperative hemoglobin drop.

Diagnosis and Management of Nephrolithiasis in Children

The incidence of kidney stones in children is increasing. Approximately two-thirds of pediatric cases have a predisposing cause. Children with recurrent kidney stones have an increased higher risk of developing chronic kidney. A complete metabolic workup should be performed. Ultrasound examination is the initial imaging modality recommended for all children with suspected nephrolithiasis. A general dietary recommendation includes high fluid consumption, dietary salt restriction, and increased intake of vegetables and fruits. Depending on size and location of the stone, surgical intervention may be necessary. Multidisciplinary management is key to successful treatment and prevention.

Slowly developing urinothorax in a child due to intrapleural migration of DJ stent-a rare complication of percutaneous nephrolithotomy

Percutaneous nephrolithotomy is usually considered as safe and effective in the management of renal stones in pediatric population. Urinothorax defined as presence of urine in pleural cavity is a rare complication of percutaneous nephrolithotomy. We present a rare case of slowly developing urinothorax in a 9-year-old boy following PCNL due to migration of DJ stent into the pleural cavity. The case was managed by intracostal tube drainage and repositioning of DJ stent.

Outcomes of Mini-Percutaneous Nephrolithotomy in Children and Adolescents: A 10-Year Single-Centre Experience From Kuwait

The current study retrospectively reviewed data for all children and adolescents who underwent mini-percutaneous nephrolithotomy (PCNL) at Ibn Sina Hospital and Sabah Al Ahmad Urology Centre in Kuwait over 10 years. Accordingly, the 40 patients underwent mini-PCNL. Among them, 21 patients (52.5%) had varying degrees of hydronephrosis, with mild to moderate severity accounting for nearly half of them, whereas six (15%) had multiple stones. The median operative time was 54.5 (43.3-64) minutes. Moreover, 11 patients needed flexible ureteroscopy (URS) and double-J (DJ) ureteric stent, and one patient required DJ ureteric stent only. None of the cases developed intraoperative bleeding. The median hospital stay of the included patients was three (2.3-4) days. Residual stone was observed in 11 patients (27.5%), with a median size of 3 (2 to 7) mm. The incidence of postoperative complications was 27.5% (n = 11 patients), with three patients experiencing postoperative bleeding (7.5%) and eight patients developing a fever (20%). All patients had mild postoperative pain. However, no leakage, sepsis, or pelvic injury occurred. None of the patients required revision. In conclusion, mini-PCNL was a safe and effective procedure in children and adolescents with renal stones.

Is Mini Percutaneous Nephrolithotomy a Game Changer for the Treatment of Renal Stones in Children?

Background

Mini percutaneous nephrolithotomy (MPCNL) is a newer surgical procedure that has changed the management of paediatric renal stones.

Objective

To evaluate MPCNL morbidity and success rates for renal stones as a function of patient age in a paediatric cohort.

Design, setting, and participants

This was a retrospective case series that included 143 consecutive patients younger than 17 yr who underwent MPCNL at our institution between January 2016 and November 2020. The patients were categorised into three different age groups: <6 yr (n = 71, 49.7%), 6–11 yr (n = 44, 30.8%), and 12–17 yr (n = 28, 19.6%). MPCNL was performed in all patients through 16–20Fr tracts.

Outcome measurements and statistical analysis

The stone-free rate, perioperative complications, tract number, operative time, postoperative haemoglobin change, and hospitalisation time were evaluated for each age group.

Results and limitations

MPCNL was performed in 143 paediatric patients (88 boys and 55 girls; mean age 6.53 yr). The mean stone burden (± standard deviation) was 2.096 ± 1.01 cm in group one, 2.05 ± 1.05 cm in group two, and 3.46 ± 19.94 cm in group three; group three was significantly larger (p = 0.001). After a single MPCNL session, 92.42% of patients experienced complete stone clearance. All age groups were similar in terms of stone-free rate (p = 0.82), hospitalisation time (p = 0.94), postoperative haemoglobin change (p = 0.06), and perioperative complications (p = 0.62). However, stone size (p = 0.009), stone complexity (p = 0.001), number of access points (p = 0.03), and operative time (p = 0.009) were higher in the group aged 12–17 yr.

Conclusions

MPCNL is an effective and safe procedure in younger as well as older children. Age should not be considered a limiting factor for MPCNL in children, and MPCNL should be considered the primary option for treating paediatric renal stones when PCNL is indicated.

Patient summary

Our results show that surgical removal of kidney stones through an incision in the skin and using miniaturised instruments is an effective and safe procedure for children.

Comparison of Outcomes of Percutaneous Nephrolithotomy (PCNL) Between Adults and Pediatrics Population: A Single-Center Retrospective Study

Introduction: Percutaneous nephrolithotomy (PCNL) has almost completely replaced open surgery for kidney stones because of continuous advancements in the method since the first PCNL was performed in 1976. The aim of this study is to compare the characteristics and outcomes of adult patients and pediatric patients who had undergone PCNL.

Methodology: A retrospective study was conducted at the Sindh Institute of Urology and Transplantation (SIUT) Hospital in Karachi, Pakistan. It included the data of patients who underwent PCNL from January 2015 to January 2022 at the SIUT hospital. The primary outcome variable was the stone-free rate (SFR). Secondary outcomes included length of hospital stay, and complications were assessed using modified Clavien classification system

Results: There is no significant difference in the SFR at discharge between pediatric and adult patients (86.67% vs 88.69%, p=0.634). There is no significant difference between the two groups in relation to the total length of hospital stay (p=0.446). Moreover, 12.50% and 11.11% of adults and children developed complications, respectively, after the procedure. The percentages are not significantly different between the two groups (p=0.266).

Conclusion: The current study using standardized and consistent PCNL techniques shows that SFR is similar in both adults and children, and there is no difference in complications between adults and children.

Surgical treatment of pediatric urolithiasis

Introduction: Surgical treatment of urolithiasis in children is quite complex and specific due to certain anatomical and functional features of childhood. Methods of surgical treatment at this age are: extracorporeal lithotripsy (ESWL), intracorporeal (endoscopic) lithotripsy - pneumatic and laser, percutaneous nephrolithotripsy (PCNL) and open surgery. Aim: The aim of this study was evaluation of the effects of ureterorenoscopy and endoscopic lithotripsy in children, as methods of minimally invasive surgical treatment. Material and methods: The retrospective study was conducted at the Institute for Mother and Child Health Care of Serbia "Dr Vukan Cupic" in Belgrade from 2010 to 2020. The study included 112 patients (50 boys and 62 girls) aged 1-18 years with urolithiasis, treated by endoscopic (laser or pneumatic) lithotripsy. The retrospective study was conducted at the Institute for Mother and Child Health Care of Serbia "Dr Vukan Cupic" in Belgrade from 2010 to 2020. The study included 112 patients (50 boys and 62 girls) aged 1-18 years with urolithiasis, treated by endoscopic (laser or pneumatic) lithotripsy. Results: After one ureterorenoscopy, the calculus was successfully disintegrated in 87 (78%) patients: in the renal pelvis in 22 (79%), in the upper pole calices of the kidney in 14 (100%), in the lower pole calices in 10 (50%), in the proximal segment of the ureter in 10 (83%), in the distal segment of the ureter in 27 (79%), in the bladder in 4 (100%) cases. In 19 (17%) patients the second intervention was necessary: in the renal pelvis in 28 (100%), in the upper pole calices in 14 (100%), in the lower pole calices in 14 (70%), in the proximal segment of the ureter in 12 (100%), in the distal segment of the ureter in 34 (100%) and in the bladder in 4 (100%) patients. Conclusion: The primary treatment of pediatric urolithiasis is ureterorenoscopy in combination with pneumatic or laser lithotripsy. It is successfully used in all segments of the urinary tract. The procedure is partially limited in the lower pole calices of the kidney, due to anatomical circumstances and mechanical limitations of the instruments.

Minimally invasive surgery for pediatric renal and ureteric stones: A therapeutic update

The incidence of pediatric urolithiasis (PU) is growing worldwide. The corresponding therapeutic methods have become a research hot spot in pediatric urology. PU has the characteristics of abnormal metabolism, easy recurrence, and immature urinary system development, which make its treatment different from that of adults. Pediatric urologists should select the optimal treatment modality to completely remove the stones to prevent recurrence. Currently, the curative treatments of PU include extracorporeal shock wave lithotripsy (ESWL), ureteroscopy, retrograde intrarenal surgery, percutaneous nephrolithotomy (PCNL), laparoscopic, robot-assisted laparoscopic, and open surgery. This review aims to conduct a therapeutic update on the surgical interventions of both pediatric renal and ureteric stones. It accentuates that pediatric surgeons or urologists should bear in mind the pros and cons of various minimally invasive surgical treatments under different conditions. In the future, the treatment of PU will be more refined due to the advancement of technology and the development of surgical instruments. However, a comprehensive understanding of the affected factors should be taken into account by pediatric urologists to select the most beneficial treatment plan for individual children to achieve precise treatment.

Mini-percutaneous nephrolithotomy versus shock wave lithotripsy for the medium-sized renal stones

INTRODUCTION

The aim of this study was to assess the clinical outcomes of mini-percutaneous nephrolithotomy (Miniperc) and shock wave lithotripsy (SWL) for medium-sized renal stones.

EVIDENCE ACQUISITION

A literature search was performed in February 2020 using the Pubmed, Web of Science and Embase. The outcome measurements between two procedures were stone-free rates (SFR), complication rates, operative time, hospitalization stay time, re-treatment rate, auxiliary procedures rate and efficiency quotient. Results were pooled by Review Manager version 5.3 software.

EVIDENCE SYNTHESIS

Seven studies on 936 patients (N.=471 for SWL and N.=465 for Miniperc) were included. Miniperc was associated with a higher SFR (OR: 0.25; P<0.00001). In addition, we performed a subgroup analyses for pediatric renal stones and lower pole stones, pooled results also favored Miniperc for higher SFR. SWL was associated with higher auxiliary procedure (OR: 3.32; P<0.00001), higher re-treatment rate (OR: 19.19; P<0.00001) and lower EQ (OR: 0.18; P=0.0003) compared with Miniperc. Besides, SWL was associated with a lower complication rate (OR: 0.36; P=0.0001), shorter operative time (WMD: -34.01; P<0.00001), fluoroscopy time (WMD: -134.48; P<0.00001) and hospital time (WMD: -49.11; P<0.00001) compared with Miniperc.

CONCLUSIONS

Miniperc offers a significantly higher SFR, lower auxiliary procedure and re-treatment rate, but SWL was associated with fewer complications.

Impacted urethral stone presenting as urinary retention in a child

A seven-year-old boy was referred to our Accident and Emergency department with a history of urinary retention secondary to urinary tract infection and an inability to pass a urethral catheter. He had been treated a month before for suspected pyelonephritis by the referring hospital. Attempts at urethral catheterisation failed, and he was taken to theatre for cystourethroscopy and catheter placement. At this time, an impacted urethral stone was discovered. Because it could not be dislodged, a suprapubic catheter was placed, and the child was brought back at a later date for definitive management. Investigations revealed a pure calcium oxalate stone that was secondary in origin. There has been no recurrence during a follow-up period of 6 months.This illustrates that while rare, urethral stones do occur in children and should be considered in children presenting with urinary retention, haematuria and/or abdominal pain.

Which factors affect the success of pediatric PCNL? Single center experience over 20 years

OBJECTIVE

We aimed to investigate the impact of surgeons' experience on pediatric percutaneous nephrolithotomy (PCNL) outcomes.

MATERIALS AND METHODS

Between June 1997 and June 2018, 573 pediatric patients with 654 renal units underwent PCNL for renal stone disease by senior surgeons. Data were divided into two groups, group-1 (n = 267), first ten years period, group-2 (n = 387); second ten years period.

RESULTS

Mean ± SD age of patients was 7.6 ± 4.9 (1-17) years. The stone-free rates (SFR) assessed after 4 weeks were 74.9% vs. 83.4% in group-1 vs. group-2, respectively (p = 0.03). The mean operation time, fluoroscopy time, and the number of patients requiring blood transfusion significantly decreased in group 2 (100.4 ± 57.5 vs. 63.63 ± 36.3, 12.1 ± 8.3 vs. 8.3 ± 5.4, and 24.3% vs. 2.9%; p < 0.001, p < 0.001, and p = 0.002 in group-1 versus group-2, respectively). On multivariate analysis, increasing stone size increased operation time (p < 0.001), fluoroscopy time (p < 0.001), intraoperative and postoperative blood transfusion rates (p = 0.006 and p = 0.018, respectively), and hospital stay (p = 0.002) but was not associated with change of glomerular filtration rate (GFR) (p = 0.71). Sheath size also correlated with increased fluoroscopy time (p < 0.001), operation time (p < 0.001), intraoperative blood transfusion (p < 0.001) and hospital stay, but sheath size did not affect postoperative blood transfusion (p = 0.614) or GFR change (p = 0.994).

CONCLUSIONS

The percutaneous nephrolithotomy (PCNL) is a minimally invasive procedure and is well accepted because of its lower complication rate and high efficiency for pediatric patients. Stone and sheath size are predictive factors for blood loss and hospital stay. During 20 years, our fluoroscopy time, operation time, blood loss, and complication rates decreased, and stone-free rate increased.

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.

Critical Application of Adult Nephrolithometric Scoring Systems to Children Undergoing Mini-Percutaneous Nephrolithotomy

Objective: To evaluate and compare the ability of the Guy's stone score (GSS), the S.T.O.N.E. nephrolithometry, and the Clinical Research Office of the Endourology Society (CROES) nomogram to predict the outcome of mini-percutaneous nephrolithotomy (MPNL) in children, and to identify which of the predictors involved in these scoring systems can separately affect this outcome. Patients and Methods: All children younger than 14 years who had MPNL in our center over a period of 3 years were included prospectively. Bivariate analyses were done to evaluate the associations of the three scoring systems and the predictors composing them with single-session stone clearance and complications. Receiver operating characteristic (ROC) curve analyses of the three scoring systems were conducted to evaluate and compare their abilities to predict the outcomes. Decision curve analyses for the three scoring systems were conducted to evaluate the clinical benefit of using each of them to predict stone clearance. Results: We consecutively enrolled 92 renal units in 89 children with a median age of 9.5 years. Single-session stone clearance was achieved in 76 (82.6%) renal units. Complications occurred with 19 (20.7%) procedures. Stone multiplicity (p = 0.043), staghorn stone (p = 0.007), prior stone treatment (p < 0.001), number of calices involved (p = 0.006), stone burden (p = 0.003), GSS (p < 0.001), S.T.O.N.E. nephrolithometry (p = 0.012), and CROES nomogram (p < 0.001) had significant associations with stone clearance. Only stone attenuation was significantly associated with complications (p = 0.031). For prediction of stone clearance, CROES nomogram demonstrated the greatest area under the ROC curve and the greatest net benefit on decision curve analyses. Conclusions: For children undergoing MPNL, CROES nomogram is the best to predict stone clearance. However, none of the studied scoring systems predicted complications efficiently.

Miniature semi-rigid ureteroscopy with holmium-yttrium-aluminium-garnet laser vs shockwave lithotripsy in the management of upper urinary tract stones >1 cm in children

Objective

To compare the efficacy and safety of miniature semi-rigid ureteroscopy (URS) with holmium (Ho)-yttrium-aluminium-garnet (YAG) laser lithotripsy vs shockwave lithotripsy (SWL) for treating upper urinary tract (UUT) calculi >1 cm in children.

Patients and methods

Children with unilateral single UUT ureteric stones of >1 cm were prospectively enrolled in this study. Patients were randomly divided into two groups: Group 1, treated with SWL; and Group 2, treated with URS (6/7.5 F) and laser lithotripsy. The patients’ characteristics, stones demographics, operative time, adjunctive procedures, stone-free rate (SFR), re-treatment rate, and complications were statistically analysed and compared. Success was defined as stone-free status (no stone residual of ≥0.3 cm) at 1 month from the initial treatment without any auxiliary procedures.

Results

In all, 68 patients with UUT stones met our inclusion criteria. There were no significant differences between the two groups for patient or stone demographics. In Group 1, the SFR was 26/34 (76.4%) and in Group 2 it was 33/34 (97.1%) (P = 0.03). A total of 12 auxiliary procedures in Group 1 and two in Group 2 were needed to reach a 100% SFR (P = 0.014). There were no significant differences between the two groups for operative times, adjunctive procedures, number of complicated cases or complications of Grade ≥III (P = 0.65, P = 0.23, P = 0.77, and P = 0.62, respectively).

Conclusion

Miniature semi-rigid URS with Ho-YAG laser lithotripsy for UUT ureteric stones of >1 cm in children was more effective than SWL in terms of SFR and re-treatment rate, with no significant difference in the rate or grade of complications.

Abbreviations

EQ: efficiency quotient; KUB: plain abdominal radiograph of the kidneys, ureters and bladder; RCT: randomised controlled trial; SFR: stone-free rate; SWL: shockwave lithotripsy; URS: ureteroscopy; US: ultrasonography/ultrasound; URS: ureteroscopy; UUT: upper urinary tract; YAG: yttrium-aluminium-garnet

Mini- versus standard percutaneous nephrolithotomy for treatment of pediatric renal stones: is smaller enough?

INTRODUCTION

Miniaturized percutaneous nephrolithotomy (PCNL) has gained increased popularity owing to efforts in recent years to lower peri-operative morbidity while maintaining a high stone-free rate (SFR).

OBJECTIVE

The outcomes of pediatric renal stones treated by mini-PCNL (MPCNL) versus standard PCNL (SPCNL) were retrospectively assessed.

STUDY DESIGN

A retrospective data analysis of 134 consecutive patients younger than 17 years who underwent PCNL between January 2014 and July 2018 was performed. The patients were categorized into two treatment groups depending on the tract size and instruments used. Seventy-five patients were treated by SPCNL using adult instruments via a 22-26 Fr tract, and 59 patients were treated by MPCNL using pediatric instruments via a 16-20 Fr tract.

RESULTS

A total of 134 children (SPCNL = 75; MPCNL = 59) underwent PCNL and subsequent evaluation. Patient demographics and stone characteristics were comparable between the two groups. The mean stone size ranged from 1.9 ± 1.162 cm in the MPCNL group to 2.2 ± 1.424 cm in the SPCNL group, and the overall SFR was 89.5% in the MPCNL group and 94.7% in the SPCNL group. When comparing the common characteristics, no significant difference was found between the two surgical access regarding the mean operative duration, SFR, incidence of peri-operative complications, and the rate of bleeding requiring a blood transfusion. Conversely, the mean postoperative hemoglobin decrease was significantly lower in the MPCNL group relative to the SPCNL group, at 0.354 ± 0.299 g versus 0.568 ± 0.332 g, respectively (P = 0.001). In addition, the mean duration of hospitalization was significantly lower in the MPCNL group than in the SPCNL group, at 1.91 ± 1.154 days compared with 2.41 ± 1.14 days, respectively (P = 0.014).

DISCUSSION

Herein, the authors report the first systematic review of the first center in the locality treating this cross section of patients. This review reveals that the use of these smaller instruments can deliver a strong safety profile while achieving good stone clearance. As an alternative to decreasing the peri-operative morbidity associated with SPCNL, MPCNL can be conveniently used without affecting the outcomes of the procedure. It is a safe and feasible procedure for maximal clearance of stones and should comprise the treatment of choice-regardless of age-for experienced endourologists.

CONCLUSION

MPCNL represents a valuable way of treating simple and complex renal stones in children, with an operative time, SFR, and overall complication rate comparable with those of SPCNL. Mini-PCNL resulted in shorter hospitalization and fewer hemoglobin drops.

Percutaneous nephrolithotomy of staghorn renal stones in pediatric patients using adult-sized instrument

INTRODUCTION

In this study, we aimed to evaluate the safety and efficacy of the percutaneous nephrolithotomy procedure performed with adult-sized instruments in pediatric cases with staghorn kidney stone.

METHODS

We retrospectively evaluated the efficacy and safety of 94 percutaneous nephrolithotomy procedures performed during 15 years in a single center for 82 pediatric patients with staghorn calculi using adult-sized instruments (24-Fr nephroscope). Stone free status was defined as complete clearance of the stones or the presence of insignificant residual stones of <3 mm in diameter.

RESULTS

The mean age was 108 ± 53 months (range, 14-180 months). There were 39 patients (48%) with complete staghorn stones and 43 cases (52%) with partial staghorn. We fulfilled 91.4% of operations through a single access. The stone free rate was 86.6% after one percutaneous nephrolithotomy session. In total, seven patients referred for shock wave lithotripsy and four cases were scheduled for the second percutaneous nephrolithotomy session. Fever occurred in 18 patients (21%) and bleeding requiring transfusion in four children (5%). Prolonged leakage from nephrostomy site requiring anesthesia for double J stent placement occurred in one patient. No grade IV or V Clavien complication occurred.

CONCLUSION

The success rate and complications of percutaneous nephrolithotomy with adult-size instruments in pediatric patients are acceptable.

Change of Trends in the Treatment Modality for Pediatric Nephrolithiasis: Retrospective Analysis of a US-Based Insurance Claims Database

Purpose: The objective of this study was to show the prevalence and investigate treatment trends of pediatric nephrolithiasis based on a large population of U.S. insurance individual's data. Materials and Methods: This research involved a retrospective observational cohort study. Administrative claims data were extracted from the IBM^® MarketScan^® Research Database. We included all patients newly diagnosed with nephrolithiasis, aged <18 years old at the time of diagnosis from January 1, 2007, to December 31, 2014. The patient cohort with nephrolithiasis was selected using the International Classification of Disease, 9th Revision, Clinical Modification (ICD-9-CM) code for nephrolithiasis. Each treatment method was searched by Current Procedural Terminology (CPT) code. Results: A total of 28,014 patients were found to have nephrolithiasis in our cohort. Of nephrolithiasis patients, 701 (2.5%) patients were treated by surgical methods. The mean age of patients at the time of treatment was 13 years old. Extracorporeal shockwave lithotripsy (SWL) was the most used treatment modality during the period. SWL was performed in 66% of patients. The number of cases of SWL did not tend to change according to year, whereas retrograde intrarenal surgery (RIRS) tended to increase from 15% to 31%. Percutaneous nephrolithotripsy (PCNL) decreased from 13% to <10 cases. The number of open surgeries was very small and did not show any tendency. Conclusion: During the study period, SWL is stable. RIRS has become more popular in treating renal stones, whereas PCNL has decreased. These results suggest that the RIRS has become more popular than PCNL in treating large renal stones.

Minimally Invasive Management of Uroliths in Cats and Dogs

Urolithiasis commonly affects cats and dogs. The American College of Veterinary Internal Medicine established guidelines for the treatment of uroliths that reflect modern techniques prioritizing minimally invasive procedures with an emphasis on prevention strategies to limit morbidity and mortality. Extracorporeal shockwave lithotripsy and endoscopic nephrolithotomy constitute some of the minimally invasive treatment modalities available for upper urinary tract uroliths. Cystoscopic-guided basket retrieval, cystoscopic-guided laser lithotripsy, and percutaneous cystolithotomy are minimally invasive options for the management of lower urinary tract uroliths. Following stone removal, prevention strategies are essential to help reduce morbidity and mortality associated with stone recurrence.

Treatment of upper urinary tract stones with flexible ureteroscopy in children

INTRODUCTION

This single-centre, retrospective study aimed to assess the efficacy and safety of flexible ureteroscopy (FURS) combined with holmium laser lithotripsy in treating children with upper urinary tract stones.

METHODS

From June 2014 to October 2015, a total of 100 children (74 boys and 26 girls) with upper urinary tract stones were treated using FURS. A 4.7 Fr double-J stent was placed two weeks before operation. Patients were considered stone-free when the absence of residual fragments was observed on imaging studies. The preoperative, operative, and postoperative data of the patients were retrospectively analyzed.

RESULTS

A total of 100 pediatric patients with a mean age of 3.51±1.82 years underwent 131 FURS and holmium laser lithotripsy. Mean stone diameter was 1.49±0.92 cm. Average operation time was 30.8 minutes (range 15-60). The laser power was controlled between 18 and 32 W, and the energy maintained between 0.6 and 0.8 J at any time; laser frequency was controlled between 30 and 40 Hz. Complications were observed in 69 (69.0 %) patients and classified according to the Clavien system. Postoperative hematuria (Clavien I) occurred in 64 (64.0 %) patients. Postoperative urinary tract infection with fever (Clavien II) was observed in 8/113 (7.1%) patients. No ureteral perforation and mucosa avulsion occurred. The overall stone-free rate of single operation was 89/100 (89%). Stone diameter and staghorn calculi were significantly associated with stone-free rate.

CONCLUSIONS

FURS and holmium laser lithotripsy is effective and safe in treating children with upper urinary tract stones.

Comparison of outcomes of tubed versus tubeless percutaneous nephrolithotomy in children: A single center study

Objective

To evaluate and compare the effectiveness of tubeless percutaneous nephrolithotomy (PCNL) and tubed PCNL by using small bore nephrostomy tube (12Fr) in children for the management of nephrolithiasis.

Material and methods

This study was a retrospective analysis of 35 children where tubed PCNL (Group 1) was done in 18, and tubeless PCNL (group 2) in 17 patients from January 2010 to December 2016. Charts were reviewed for age, mass, stone size, operative time, hospital stay and stone-free rates. These variables were compared between the two groups. SPSS version 21 was used for data analysis. The data were shown as mean±standard deviation for continuous variables. Categorical variables were presented in percentages.

Results

There is no difference in terms of age, stone sizes, operative times, hospital stays, stone-free rates and post-PCNL complications between the two groups (p>0.05). The mean drop in hemoglobin level was 0.7±0.1 g/dL and 1.3±0.2 g/dL in Groups 1 and 2, respectively (p=0.01).

Conclusion

Tubeless PCNL in children is a safe option in well selected cases.

Is mini-percutaneous nephrolithotomy a safe alternative to extracorporeal shockwave lithotripsy in pediatric age group in borderline stones? a randomized prospective study

PURPOSE

The extracorporeal shockwave lithotripsy (ESWL) remains the most common first line of treatment for renal stones in the pediatric population. The purpose of this study is to evaluate and compare the outcomes of the ESWL and mini-percutaneous nephrolithotomy (mini-PCNL).

PATIENTS AND METHODS

A total of 108 patients younger than 12 years of age with 1-2 cm single renal stone (pelvic or calyceal) were randomized into two groups, each containing 54 patients. Patients in group A were subjected to mini-PCNL using 16.5 Fr percutaneous sheath while those in group B underwent ESWL using Dornier Compact Sigma.

RESULTS

The stone-free rate (SFR) after first session was 88.9% (48 cases) and 55.6% (30 cases) for groups A and B, respectively. The difference is highly statistically significant P = 0.006. Two patients (3.7%) in group A needed 2nd session of PCNL, while 18 patients (33.3%)in group B needed a 2nd session, of theses 18 patients six patients needed a 3rd session of ESWL. After the third session of ESWL and second look PCNL the stone-free rates were 92.59% (50 cases) and 88.89% (48 cases) for groups A and B, respectively, (P = 0.639), which is statistically insignificant. The mean hospital stay and fluoroscopy exposure were significantly longer in the mini-PCNL group. The complication rate in groups A and group B were (22.2%) and (14.8%), respectively, which is statistically insignificant (P = 0.484).

CONCLUSIONS

According to Clavien grade of complications mini-PCNL is a safe procedure, and after three session of ESWL, mini-PCNL has a similar stone-free rate with a lower retreatment rate. However, the mini-PCNL has more radiation exposure, and requires a longer hospital stay.

Management of Pediatric Urolithiasis Using a Combination of Laparoscopic Lithotomy and Pyeloscopy

BACKGROUND

Minimally invasive procedures have become the standard option for treatment of urinary stones; the use of more invasive techniques is not a common practice currently. This emergent technology is not always available and laparoscopy is the alternative option. There are few reports of laparoscopic management for urinary lithiasis in pediatric patients. This study is about the use of laparoscopic surgery combined with pyeloscopy as a feasible first-line treatment for pediatric urolithiasis in renal and proximal ureteral locations.

PATIENTS AND METHODS

We reviewed the records of 14 patients with renal and proximal ureteral stones who underwent laparoscopic pyelolithotomy and pyeloscopy in a period from January 2011 to July 2016. The outcome measures were needed for auxiliary procedures, treatment success, and complication rates.

RESULTS

A total of 16 procedures were carried out in 14 patients, 15 transperitoneal and 1 retroperitoneal laparoscopic pyelolithotomies were done. It was necessary to perform upper ureterolithotomies to remove ureteral stones in 2 cases. The holmium laser and/or pneumatic lithotripter were used to fragment staghorn calculi. Some of the complications were blood transfusion in 12.5% and self-limited urinary leak in 18.7% of the patients. The success rate after undergoing one procedure was 92.8%.

CONCLUSIONS

Transperitoneal or retroperitoneal laparoscopic lithotomy is a safe and feasible procedure for the treatment of pediatric urolithiasis. It can be an alternative to shock-wave lithotripsy and percutaneous nephrolithotomy when these are not feasible or possible.

Efficacy and safety of percutaneous nephrolithotomy with adult standard size instruments in children under 3 years of age: a 10 years single-center experience

BACKGROUND

Using percutaneous nephrolitotomy (PCNL) with large adult instruments in treatment of pediatricurolithiasis is still in debate. This study was conducted to evaluate the efficacy and safety of PCNL with adult's instrument in treatment of patients less than 3 years old.

METHODS

Data on patient characteristics and outcomes for 261 consecutive children undergoing PCNL at a Labbafinejad University Hospital were collected prospectively from September 2006 to February 2016. Thirty-two children, with 34 renal units, who were treated with PCNL were enrolled in the study. All PCNL procedures were performed via subcostal approach with one access tract in all of them. Postoperative complications were evaluated according to the modified Clavien grading system.

RESULTS

The mean age of patients was 19.4 ± 6.2 months. Two patients had bilateral stones; thus, PCNL was performed on 34 kidney units. The mean size of the largest stone diameter was 17.5 ± 7.8 mm. The mean duration of procedures was 121.52 ± 29.05 minutes, ranging from 60 to 180 minutes. The most common complication was fever (n = 9, 26.4%), and hemorrhage that needs transfusion was the second one (n = 4, 11.7%). Seventeen patients with complications were in the first degree of Clavien complication system and five of them were in the second degree.

CONCLUSIONS

Due to our experience, utilizing PCNL with adult-sized instruments in management of urolithiasis in less than 3 years old children appeared to be effective and relatively safe.

Percutaneous endoscopic treatment for urinary stones in pediatric patients: where we are now

BACKGROUND

Percutaneous nephrolithotomy (PCNL) has been adopted for pyelo-calyceal stones treatment in pediatric patients, starting from the 90's. Very recently, miniaturization of endoscopic instruments allowed less invasive procedures with low complication rate. We reviewed our experience on upper tract stone treatment utilizing two different percutaneous accesses, focusing on the recent new miniaturized devices offered for pediatric renal stones.

METHODS

Patients presenting upper tract urinary stones observed from January 2011 to December 2015 and treated by percutaneous renal access were prospectively evaluated: age, sex, metabolic issues, associated abnormalities, treatment modalities, hospital stay and complication rate were recorded in a specific database. Two different endourological percutaneous modalities were adopted, depending to the stone size and position. PCNL was performed through a direct calyceal puncture under ultrasonographic and fluoroscopic guidance and Amplatz access dilatation till 24 Fr. Ballistic energy was used for fragmentation. Micropercutaneous (Microperc) procedure was recently offered utilizing a 4.85 Fr metallic needle and Holmium:YAG laser lithotripsy under direct vision through a 0.9 mm high resolution optic flexible wire connected with a telescope.

RESULTS

Thirty-eight percutaneous access to pyelo-calyceal renal stones were performed on a total of 108 children treated for upper tract stones, aged 4 to 18 years (mean age 7.5 years). The overall number of procedures was 144 (36 repeated procedures). Cystinuria was diagnosed in 5 patients. PCNL was adopted in 28 patients, Microperc was utilized in 8 patients. Hemoglobin dropdown was limited to 1.20±0.80 mg% in PCNL and was not significant in Microperc. No blood transfusion was needed. No significant complications were observed. Stone free rate or minimal not significant residuals were achieved in 82% of PCNL and in 87.5% of Microperc, after a single procedure.

CONCLUSIONS

Percutaneous endoscopic treatment of renal calculi is feasible in pediatric age, with high success rate in a single step. Advanced miniaturized endoscopic devices as Microperc guarantee high efficacy and reduced complication rate, but endo-urological experience and adequate learning curve are required, especially in small body weight children. Centralization of these patients in Pediatric Stone Centers is welcomed to optimize results and reduce risks.

Mini percutaneous nephrolithotomy for renal calculi in paediatric patients: A review of twenty cases

OBJECTIVE

The objective was to report our initial experience of mini percutaneous nephrolithotomy (mPCNL) performed on patients in the pediatric age group (<18 years) using a miniature nephroscope (12F).

SUBJECTS AND METHODS

A total of 20 children underwent mPCNL for renal stone extraction in the Department of Urology, Yenepoya Medical College, Mangalore, India, from February 2013 to January 2014. The patients were evaluated on the basis of parameters viz. age at the time of surgery, size and number of stones, duration of surgery, stone clearance, and postoperative complications.

RESULTS

A total of 20 mPCNLs were performed on children, with age ranging from 8 to 16 years. Three children had three stones each, six children had two stones each, eight children had one stone each, and three had multiple. The median stone burden was 1.36 cm. The procedure was via single puncture in 15 cases, and two punctures in five cases. Punctures were upper calyceal in seven cases, lower calyceal in seven cases, and combined upper and lower calyceal in six cases. The calculi were accessed by a 12F mini nephroscope, laser lithotripsy was used in 12 cases and pneumatic lithotripsy used for the rest. Total clearance was achieved in 18 out of 20 cases (90%). Postoperative complications developed in one child, in the form of sepsis.

CONCLUSION

Our initial experience concludes that mPCNL is a safe and efficacious tool for the management of renal calculi in the pediatric population.

Percutaneous nephrolithotomy in pediatric age group: Assessment of effectiveness and complications

Management of kidney stone disease in pediatric population is a challenging condition in urology practice. While the incidence of kidney stone is increasing in those group, technological innovations have conrtibuted to the development of minimally invasive treatment of urinary stone disease such as mini-percutenous nephrolitotomy (mini-PCNL), micro-PCNL, ultra mini-PCNL. In this review we tried to evaluate the effect of new teratment techniques on pediatric kidney stones.

Patient and stone characteristics associated with surgical intervention in pediatrics

Background

The incidence of kidney stones in children is increasing. While guidelines exist for acute surgical intervention, there is limited data to inform the decision as to when to intervene non-urgently.

Objectives

To identify patient and stone characteristics predicting stone surgery in children.

Design

Retrospective chart review.

Setting

Stollery Children’s Hospital, Edmonton, Alberta, Canada from 1990 to 2013.

Patients

Sixty-three children aged 0–18 years old who presented with a total of 142 stones.

Measurements

Patient’s surgical history, demographics, metabolic measures, and stone number, type, and location.

Methods

Univariate and multivariate analysis, controlling for presentation number and individual-level variation by repeated measures analysis were conducted to assess for patient and stone characteristics associated with surgical intervention.

Results

Sixty-five percent (41/63) required surgery during a mean follow-up of 19 months. Stone characteristics associated with surgical intervention by multivariate analysis included larger stone size (>6 mm), and stone composition of calcium oxalate.

Limitations

Single center study with a limited sample size and duration of follow up, thereby limiting predictive power. There were some missing data (i,e. stone type was not always available). Despite this, stone type remained significant in multivariate modeling.

Conclusion

Stone size > 6mm and composition with calcium oxalate but not patient age or symptoms associated with presentation predicted surgical intervention. These observations can be used to inform decisions as to whether urolithiasis should be surgically managed electively or observed.

Electronic supplementary material

The online version of this article (doi:10.1186/s40697-015-0057-6) contains supplementary material, which is available to authorized users.

Management of stone disease in infants

Evaluating and treating renal stone disease in infants are technically challenging. In this study, we evaluated the surgical treatment of renal stones in children under 1 year of age. We retrospectively reviewed the records of patients under 1 year old who were treated with ESWL, endourological or open surgical procedures for renal stone disease between January, 2009 and December, 2012. The patients' age, gender, stone size, stone location and number, complications, stone-free status, and postoperative complications were recorded. 19 of 121 infants with a mean age of 10.2 ± 3.07 months were treated with surgical procedures. Six (75%) of eight cystinuria patients required a surgical intervention. Retrograde endoscopic management was performed in thirteen patients (63.4%) as an initial surgical approach. There were three major (15.7%) complications. The rate of open surgical procedures was 31.6% (6 of 19 infants). The cutoff value of stone size for open surgery was 10 mm. There was a significant relationship between the conversion to open procedures and stone size, stone location, and symptom presentation especially the presence of obstruction (p < 0.05). After repeated treatments, the stone clearance rate of RIRS reached 84.6%. Retrograde intrarenal surgery is an effective and safe treatment method for renal stones in infants and can be used as a first-line therapy in most patients under 1 year old. This is especially important if an associated ureteral stone or lower pole stone that requires treatment is present and for patients with cystinuria, which does not respond favorably to ESWL.

Outcomes following 'mini' percutaneous nephrolithotomy for renal calculi in children. A single-centre study

INTRODUCTION

This retrospective review was undertaken to identify the postoperative outcomes of children undergoing 'mini' percutaneous nephrolithotomy (MPCNL) at a single institution.

OBJECTIVE

Outcomes measured included: percentage of stone clearance, postoperative analgesia requirements, the need for intraoperative or postoperative blood transfusion, length of stay and morbidity.

STUDY DESIGN

A total of 46 patients were reviewed over a two-and-a-half-year period; the mean age was 7.3 years (range: 1-16 years). The MPCNL was performed with a radiological-guided peripheral puncture, followed by dilatation of the nephrostomy tract to a maximum Amplatz sheath size of 16-French; an 11-French nephroscope was used. Stone disintegration was achieved either with pneumatic or laser lithotripsy.

RESULTS

Complete stone clearance was achieved in 35/46 children (76%). The remaining 11 children had a stone clearance rate of over 80%. No patients required intraoperative/postoperative blood transfusion. A total of 39% of patients were managed on simple/non-opiate based analgesia, with 54% requiring opioid analgesia postoperatively for less than 24 h. There were no procedure-related complications and no mortalities. The mean length of stay was 2.24 days.

DISCUSSION

The management of urolithiasis can be challenging in children. The use of percutaneous nephrolithotomy, is becoming increasingly popular in the treatment of paediatric urolithiasis. The stone clearance rate in children undergoing standard PCNL, has been reported to be 50-98% in the literature [1,2,3,4]. Samad et al. [2] in 2006, reported their experience in 188 consecutive PCNLs, using a 17Fr or 26Fr nephroscope. Their largest sub group included children aged >5-16 yrs. Within this group, 57% were treated with a 17Fr nephroscope and 43% with the 26Fr nephroscope, achieving stone clearance of only 47% with PCNL monotherapy. In this group the transfusion rate was 3% [2]. Badawy et al., reported their experience of 60 children in 1999, using a 26 or 28Fr Amplatz sheath. They reported an 83.3% stone clearance with single session PCNL, with only one procedure being abandoned due to intraoperative bleeding requiring blood transfusion [3]. In 2007, Bilen et al. reported their experience and compared the use of 26Fr, 20Fr and 14Fr (mini) PCNL. Stone size, previous surgery and the mean haemoglobin drop postoperatively did not change between the groups, however the blood transfusion rate was higher in the 26Fr and 20Fr Amplatz sheath groups. The stone clearance was highest in the 'mini PCNL' group at 90%, compared to 69.5% in the 26Fr and 80% in the 20Fr group [4]. MPCNL has become increasingly popular over recent years, with stone clearance reported as 80-85% [5-7] following a single session of MPCNL as monotherapy. In 2012, Yan et al. reported 85.2% stone clearance with mini PCNL monotherapy (tract size 14-16Fr), with no children requiring blood transfusion [6]. Zeng et al. reported their experience of 331 renal units in children, with stone clearance rates reaching 80.4% and a blood transfusion rate of 3.1% [8]. In our centre, we do not perform postoperative haemoglobin levels as a matter of routine and any investigations are performed on an intention to treat principle. Bilen et al. reported no blood transfusions being required in their cohort of patients undergoing MPCNL [4] and this is supported by Yan et al. [6].

CONCLUSION

Mini PCNL is an effective and safe procedure for the treatment of paediatric renal stones. In the present series, all children achieved greater than 80% stone clearance, none received a blood transfusion (intra/postoperatively) and there were no mortalities. Postoperative pain was managed with simple analgesia in 39%; however, the majority required opiate analgesia for less than 24 hours.

Effect of urinary stone disease and its treatment on renal function

Urolithiasis is a common disease that affects urinary tract in all age groups. Both in adults and in children, stone size, location, renal anatomy, and other factors, can influence the success of treatment modalities. Recently, there has been a great advancement in technology for minimally invasive management of urinary stones. The epoch of open treatment modalities has passed and currently there are much less invasive treatment approaches, such as percutaneous nephrolithotomy, ureteroscopy, shockwave lithotripsy, and retrograde internal Surgery. Furthermore, advancement in imaging technics ensures substantial knowledge that permit physician to decide the most convenient treatment method for the patient. Thus, effective and rapid treatment of urinary tract stones is substantial for the preservation of the renal function. In this review, the effects of the treatment options for urinary stones on renal function have been reviewed.

Contemporary Management of Medium-Sized (10-20 mm) Renal Stones: A Retrospective Multicenter Observational Study

PURPOSE

To evaluate contemporary management approaches to medium-sized (10-20 mm) renal stones.

PATIENTS AND METHODS

A total of 935 patients treated for medium-sized renal stones (10-20 mm) between July 2012 and March 2014 were included in the study program. Contemporary minimally invasive approaches applied in the management of such stones were evaluated and compared.

RESULTS

The cohort consisted of 561 male (60%) and 374 female (40%) patients. Of the 935 patients with medium-sized renal calculi, 535 (57.2%) were treated with shockwave lithotripsy (SWL), 201 (21.4%) with retrograde intrarenal surgery (RIRS), 110 (11.7%) with minimally invasive percutaneous nephrolithotomy (miniperc), and the remaining 89 (11.7%) patients with micropercutaneous nephrolithotomy (microperc). In the SWL group, stones were located mostly in the pelvis (51%), while in the miniperc and microperc groups, they were located mainly in the lower pole (46%, 53%, respectively). Stone-free rates after a single session were 77.2%, 86.1%, 88.8%, and 83.6% in the SWL, RIRS, microperc, and miniperc groups, respectively. Although no serious complications (above Clavien level III) were noted in any of the groups evaluated, Clavien I to II complications were common in the miniperc group.

CONCLUSION

Although SWL is the preferred treatment option for patients with medium-sized (10-20 mm) renal stones, endourologic methods also have been found to have a significant role. Relatively lower complication rates along with higher stone-free status observed with the RIRS technique compared with percutaneous approaches have made this method a valuable option in the management of such stones in recent years.

Percutaneous nephrolithotomy in children: A preliminary report

Objectives:

The recurrence of pediatric nephrolithiasis, the morbidity of repeated open surgical treatment as well as our experience in percutaneous nephrolithotomy (PNL) in adult patients, all derived us to shift to PNL for managing renal stones >1.5 cm in pediatric patients. Our aim of this study is to evaluate the safety and efficacy of PNL in pediatric patients.

Materials and Methods:

During the period of the month between May 2011 and April 2013, 38 children (47 renal units) underwent PNL for renal stones 1.5-5 cm in length. Patient demographics, stone characteristics, and clinical outcome were prospectively studied. Data of those who underwent conventional and tubeless PNL were compared. Median follow-up period was 12 months (range: 6-24).

Results:

The median age at presentation was 8-year (range: 3-12). The operative time ranged from 30 to 120 min (median 90). Overall stone clearance rate was 91.5% after single PNL. The median hospital stay was 3 days. Auxiliary procedures were successful for the remaining 4 patients (nephroscopic clearance in one and shockwave lithotripsy in 3). Tubeless PNL was performed in 17 renal units with a comparable outcome to conventional ones. The perioperative complications were noted in 5/47 (10.6%) of all procedures (Clavien Grade II in 4 and Clavien Grade IIIa in 1) and were managed conservatively.

Conclusions:

Percutaneous nephrolithotomy for renal stones in pediatric patients is safe and feasible if performed by a well-experienced endourologist. Tubeless PNL is a better choice for children.

Comparison of children versus adults undergoing mini-percutaneous nephrolithotomy: large-scale analysis of a single institution

Objective

As almost any version of percutaneous nephrolithotomy (PCNL) was safely and efficiently applied for adults as well as children without age being a limiting risk factor, the aim of the study was to compare the different characteristics as well as the efficacy, outcome, and safety of the pediatric and adult patients who had undergone mini-PCNL (MPCNL) in a single institution.

Methods

We retrospective reviewed 331 renal units in children and 8537 renal units in adults that had undergone MPCNL for upper urinary tract stones between the years of 2000–2012. The safety, efficacy, and outcome were analyzed and compared.

Results

The children had a smaller stone size (2.3 vs. 3.1 cm) but had smilar stone distribution (number and locations). The children required fewer percutaneous accesses, smaller nephrostomy tract, shorter operative time and less hemoglobin drop. The children also had higher initial stone free rate (SFR) (80.4% vs. 78.6%) after single session of MPCNL (p<0.05); but no difference was noted in the final SFR (94.7% vs. 93.5%) after auxiliary procedures. The complication rate (15.6% vs. 16.3%) and blood transfusion rate (3.1% vs. 2.9%) were similar in both group (p>0.05). Both groups had low rate of high grade Clavien complications. There was no grade III, IV, V complications and no angiographic embolization required in pediatric group. One important caveat, children who required multiple percutaneous nephrostomy tracts had significant higher transfusion rate than in adults (18.8% vs. 4.5%, p = 0.007).

Conclusions

This contemporary largest-scale analysis confirms that the stone-free rate in pediatric patients is at least as good as in adults without an increase of complication rates. However, multiple percutaneous nephrostomy tracts should be practiced with caution in children.

Morbidity and efficacy of ureteroscopic stone treatment in patients with neurogenic bladder

PURPOSE

There is a lack of information on the safety and efficacy of ureteroscopy in the neurogenic bladder population. We hypothesized that ureteroscopy in patients with neurogenic bladder would be associated with an increased risk of complications and a lower stone clearance rate than in patients without neurological impairment.

MATERIALS AND METHODS

We reviewed a local registry of patients with ICD-9 codes for urolithiasis between 2004 and 2012. The study cohort was assembled from all eligible patients with neurogenic bladder and a randomly selected control group that had undergone ureteroscopy. Statistical analysis of demographic variables and surgical outcomes was performed. Complications were classified according to the Clavien system. Clearance was defined by computerized tomography, renal/bladder ultrasound or direct ureterorenoscopy.

RESULTS

Ureteroscopy was performed a total of 173 times in 127 controls and a total of 45 times in 20 patients with neurogenic bladder. There was no difference between presenting episodes by gender (p = 1.0), race (p = 0.654) or body mass index (p = 0.519). Bacteriuria was associated with the stone episode in 16.4% of controls and 67% of neurogenic bladder cases (p <0.001). Median operative time was significantly longer in those with neurogenic bladder (80.5 minutes, IQR 50-110.5 vs 52, IQR 33-78, p = 0.0003). The proportion of complications was significantly different (p = 0.013). Stones cleared in 86.6% of controls compared to 63% of neurogenic bladder cases (p = 0.004).

CONCLUSIONS

Patients with neurogenic bladder have increased morbidity after ureteroscopy for upper tract calculi compared to neurologically unaffected controls. Infection has a role in this morbidity. The clearance rate is lower but the stone burden is more significant in those with neurogenic bladder.

Advances in the surgical pediatric urologic armamentarium

The surgical armamentarium of the pediatric urologist has changed greatly in the past 2 decades on account of new technology and careful adaptation of minimally invasive techniques in children. Conventional laparoscopy, robotic-assisted laparoscopy, laparoendoscopic single-site surgery, and endourologic surgery have, to varying degrees, provided new approaches to urologic surgery in the pediatric population. This article reviews the technology and adaptations behind these recent advances as well as their current applications in management of urologic disease in children.

Percutaneous nephrolithotomy in children in different age groups: data from the Clinical Research Office of the Endourological Society (CROES) Percutaneous Nephrolithotomy Global Study

OBJECTIVES

To present the overall results of paediatric percutaneous nephrolithotomy (PCNL) compared with adults. To present the indications, complications and outcomes of patients treated in the participating centres in the PCNL Global Study, as categorised in different age groups.

PATIENTS AND METHODS

The Clinical Research Office of the Endourological Society (CROES) Study was conducted from November 2007 to December 2009, and included 96 centres and >5800 patients. All children aged ≤14 years in the PCNL Global Study database were the focus of the study.

RESULTS

In all, 107 children aged ≤14 years were included in the analysis. The PCNL procedure was conducted in 13 patients (12.1%) in the supine position; tubeless PCNL was performed in 15 patients (14%); and balloon dilatation was preferred in 22 patients (20.5%). The overall mean operative duration was 97.02 min; blood transfusion rate, fever and stone-free rates were 9%, 14% and 70.1%, respectively. A comparison of the paediatric PCNL cases according to age groups showed no statistically significant differences between the subgroups for patient characteristics, co-morbidities, renal anomalies, or previous surgical history. In the evaluation of the operative details, the mean sheath size and nephrostomy tube size were larger in school-age children than the preschool children (P = 0.01 and 0.002, respectively). There was a difference in the preferred methods for confirming stone-free status, with ultrasonography preferred more in preschool children (P < 0.001). The PCNL procedure position, puncture site, dilatation method, postoperative tube application, and surgical outcomes were comparable in school- and preschool-age children. While operative details showed some differences between children and adults, the surgical outcomes were comparable.

CONCLUSIONS

A considerable number (45.7%) of the paediatric patients had a previous history of stone intervention. Based on the findings of the present study, we can suggest that PCNL can be applied safely and effectively in children in different age groups. Outcomes appear comparable with those in adults for the success and complication rates, in the presence of substantial indications, appropriate equipment and adequate experience.

Nephrolithiasis in children

Similar to adults, stone disease in the pediatric patient may present clinically as flank/abdominal pain or hematuria. Unlike in adults, pediatric stone disease is less frequent and is often associated with an underlying metabolic disorder. Because of the 50% likelihood of finding an underlying metabolic cause for stone formation in younger children, a metabolic workup is recommended for all children with stone disease, including first-time stone formers. Stone analysis, when available, can be very helpful in determining an underlying cause. If needed, all modalities of minimally invasive surgical treatment are possible for children with stones. Surgical approaches may be needed to achieve the goal of nephron preservation. Aggressive fluid intake is the mainstay of prevention for all forms of stone disease, but specific therapy targeted to the most likely underlying metabolic abnormality is often used. Newer data are now linking stone disease to CKD, thereby emphasizing the need for a better understanding and potentially more aggressive treatment approach. With increasing frequency of stone disease in the pediatric patient and increasing survival of these patients into adulthood, the adult caregiver must become familiar with different causes and treatment approaches to stone disease in young adult patients in whom disease onset began in childhood.