Pediatric urolithiasis: the current surgical management

Comparing the efficacy of extracorporeal shock wave lithotripsy and ureteroscopic lithotripsy in the treatment of proximal ureteral stones in children: A retrospective study

OBJECTIVES

Ureteroscopic lithotripsy and extracorporeal shock wave lithotripsy methods are commonly used in the treatment of proximal ureteral stones. There are no adequate studies showing which method is more effective in children. In our study, we aimed to evaluate and compare the efficacy of two treatment methods, commonly used for proximal ureteral stones in children.

METHODS

A total of 78 patients who underwent ureteroscopic lithotripsy (n = 38) and extracorporeal shock wave lithotripsy (n = 40) due to stones located in the proximal ureter between 2010 and 2021 were included in the study. Demographic data, clinical characteristics, and treatment outcomes were retrospectively analyzed. Kolmogorov-Smirnov, Chi-square, and Mann-Whitney U tests were used for statistical analysis.

RESULTS

There was no statistical difference between the demographic characteristics of the groups, except for the mean age values (p = 0.008). A statistically significant difference was found in favor of the extracorporeal shock wave lithotripsy group in terms of stone-free rates after the first intervention, complication rates requiring intervention, re-intervention rates, and the average number of anesthesia sessions per patient until stone-free status (p = 0.043, p = 0.009, p = 0.017, and p < 0.001, respectively).

CONCLUSIONS

The results of this retrospective study suggest that extracorporeal shock wave lithotripsy is the primary treatment option for single, non-complicated proximal ureteral stones.

Contemporary minimal invasıve surgical management of stones in children

Objective

Pediatric urolithiasis has been more common over the past 20 years, and urologists have unique challenges in managing it surgically because this particular demographic is recognized as one of the high-risk categories for stone recurrence. Given this reality, care focuses on maintaining renal function, achieving total stone-free status, and most importantly avoiding stone recurrences. In this presented article, we aimed to make a comprehensive review of the current minimally invasive treatment of pediatric kidney stone disease.

Methods

We evaluated the results of 74 studies following a comprehensive PubMed search till February 2023. This article was written by making use of current urology guidelines.

Results

Considering the reported occurrence of metabolic issues in up to 50% of cases in addition to the anatomic anomalies (about 30% of cases), the treatment of pediatric urolithiasis necessitates a full metabolic and urological examination on an individual basis. Timely management of metabolic imbalances and obstructive diseases is necessary. In addition to encouraging proper fluid consumption, it is advisable to improve urine volume and consider using medical therapeutics to raise urinary citrate levels. The location, content, and size of the stone(s), the morphology of the collecting system, the presence of urinary tract infection, as well as the presence of any obstruction, should all be taken into consideration while deciding on the best surgical procedure.

Conclusion

All modern endourological methods are now used in the safe and efficient care of pediatric urolithiasis as a consequence of the obvious advancements in instrument technology and expanding expertise derived from adult patients. Other minimally invasive procedures, such as ureterorenoscopy and percutaneous nephrolithotomy, require more expertise and can be successfully applied with careful management for an excellent stone-free rate with minimal morbidity. Of these procedures, shock wave lithotripsy is still the first choice in the majority of cases with upper tract calculi. Open surgery will still be the therapy of choice for pediatric patients with complicated and big stones as well as anatomical anomalies.

Minipercutaneous Nephrolithotomy in the Management of Large and Complex Renal Calculi in Children: How Effective Is It?

Purpose: To evaluate the efficacy and safety of minipercutaneous nephrolithotomy (PCNL) in the management of large and complex calculi in children. Patients and Methods: From May 2017 to April 2021, a total of 41 pediatric cases were diagnosed with large/complex renal stones (partial-total staghorn) and following a detailed biochemical evaluation and thorough radiological examination (plain abdominal radiograph, urinary ultrasound, noncontrast and/or computed tomography), all cases underwent mini-PCNL procedure for the minimal invasive management of these calculi. Preoperative, intraoperative, and postoperative data were analyzed and reported in detail. Results: A total of 41 procedures were performed in 26 boys and 15 girls (male/female = 1.73). While the age of the kids ranged from 2.5 to 10 years (mean 6.74 ± 2.76), mean size of the stones was 16.28 ± 3.43 mm (range 11-24) with a mean stone density value of 816 HU (range 550-1350). Evaluation of the success rates in terms of complete stone clearance on postoperative day 1 revealed that while 73.2% (30/41), residual fragments have been noted in 11 cases (26.8%). Size of the residual fragments ranged from 2 to 7 mm (mean 4.3). Of those children, 10 cases required flexible ureteroscopy for stone removal, and in 1 case, placement of Double-J was adequate for spontaneous passage. During a 3-month follow-up, the stone-free rate (SFR) increased to 100% without any residual fragment left. Conclusions: Mini-PCNL with holmium laser lithotripsy is an effective and safe treatment alternative in the minimal invasive management of large/complex kidney stones in children with high SFRs.

Is laparoscopic pyelolithotomy an alternative to percutaneous nephrolithotomy for treatment of kidney stones larger than 2.5 cm in pediatric patients?

PURPOSE

The aim was to compare laparoscopic pyelolithotomy and percutaneous nephrolithotomy in terms of efficacy and safety for the treatment of renal pelvis stones larger than 2.5 cm in pediatric patients.

METHODS

Our study consisted of two groups. Group 1 included 33 patients who underwent laparoscopic pyelolithotomy (LPL) between January 2013 and March 2022, and group 2 included 39 patients who underwent percutaneous nephrolithotomy (PCNL). The basic clinical parameters of the patients were recorded. Mean operation time, stone size, estimated blood loss, blood transfusion rate, postoperative hospital stay, stone-free rate, postoperative analgesia requirements, intraoperative complications, and early and late postoperative complications were compared between the two groups.

RESULTS

In our study, the mean age of the patients in groups 1 and 2 was 8.89 ± 1.58 years and 9.1 ± 1.85 years, respectively (p = 0.657). The mean stone size was 2.37 ± 0.38 cm in group 1 and 2.55 ± 0.45 cm in group 2 (p = 0.64). The mean operation time was 85.65 ± 20.55 min in group 1, while it was 76.11 ± 13.12 min in group 2 (p = 0.08). The stone-free rate was 100% in both groups. Intraoperative mean blood loss, need for postoperative analgesia, blood transfusion and intraoperative complication rates were significantly higher in the PCNL group (p < 0.01, p = 0.02, p < 0.01, p < 0.01, respectively).

CONCLUSION

Our results show that laparoscopic pyelolithotomy is a safe and effective method for pediatric patients with large kidney stones.

Ultrasound-guided mini-percutaneous nephrolithotomy in the treatment of upper urinary tract stones in children: A single-center evaluation

To evaluate the safety and efficacy of ultrasound-guided mini-percutaneous nephrolithotomy (mini-perc) for the treatment of upper urinary tract stones in children. We reviewed the records of 70 children with upper urinary tract stones who were treated with a mini-perc technique between July 2015 and April 2020. All puncture site selections and tract dilations were determined by Doppler ultrasonography. Patient age, height, weight, stone size, operation time, stone-free rate (SFR), postoperative complications, tubeless rate, and length of hospital stay (LOS) were recorded. Stone components were analysed using infrared spectroscopy. A total of 47 boys and 23 girls were included. Median weight and height of the patients were 18.5 kg and 110 cm, respectively. Median stone diameter was 2.0 cm. Median time to establish access was 4.0 min and median operation time was 25 min. Patients had median preoperative and postoperative haemoglobin levels of 121 and 113.5 g/L, median haemoglobin levels dropped to 8.0 g/L the day after surgery. No patient needed a blood transfusion. Eight children (11.4%) developed significant complications, including four cases with Clavien Grade I, one with Clavien Grade II, and three with Clavien Grade Ⅲ complications. One-day and 1-month follow-ups revealed a complete SFR of 95.7% (67/70) and 97.1% (68/70), respectively. Fifty-six patients (80.0%) did not require catheters of any type (total tubeless). Median LOS was 2.0 days. Ultrasound-guided mini-perc is safe and effective. The mini-perc technique is a feasible alternative for paediatric stone disease that does not result in major complications.

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.

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

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

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

Monogenic urinary lithiasis in Tunisian children: 25 years' experience of a referral center

OBJECTIVE

To describe the clinical, biochemical and evolutive profile of monogenic urinary lithiasis in Tunisian children followed up in a reference service, during a 25 years period.

METHODS

This was a single-center retrospective observational study of children with urolithiasis, conducted in the pediatric nephrology department in Charles Nicolle Hospital, Tunis, Tunisia over 25 years (January 1st, 1996 to December 31, 2020). Children≤18 of age with urolithiasis with or without nephrocalcinosis related to a monogenic disease were included in our study.

RESULTS

A total of 66 children were included in our study. Patients were 5.92±3.48 years of age at the time of urolithiasis diagnosis, and 5.33±3.66 years of age at the time of the underlying pathology diagnosis. The inherited urolithiasis disorders found in our series were: primary hyperoxaluria in 44 cases, cystinuria in 9 cases, Lesch Nyhan syndrome in 5 cases. Renal tubular acidosis was found in 3 cases, and hereditary xanthinuria in 2 cases. Bartter syndrome, adenine phosphoribosyltransferase deficiency and Hereditary hypophosphatemic rickets with hypercalciuria were found in 1 case each. After an average follow-up of 6.45±3.79 years, six patients were in end-stage renal disease. Three patients had died, all of them being followed for primary hyperoxaluria type 1.

CONCLUSIONS

Monogenic urinary lithiasis, although rare, are most likely under-diagnosed in countries with high consanguinity such as Tunisia. The screening of these diseases seems to be of primary importance because of their significant morbidity.

Use of retrograde intrarenal surgery (RIRS) compared with mini-percutaneous nephrolithotomy (mini-PCNL) in pediatric kidney stones

OBJECTIVE

We aimed to compare the cost-effectiveness and safety of retrograde intrarenal surgery (RIRS) and mini-percutaneous nephrolithotomy (mini-PCNL) for pediatric kidney stones management.

PATIENTS AND METHODS

Ninety pediatric patients with single or multiple renal stones 1-3 cm in diameter were collected prospectively and equally divided into two groups to undergo RIRS or mini-PCNL. The groups were compared for fluoroscopy and operative time, postoperative hospital stay time, stone-free rate (SFR), need for auxiliary procedures, and cost as well as complications.

RESULTS

There were no differences found between RIRS and mini-PCNL groups with regard to operative time and postoperative DJ stent application, while the mean of fluoroscopy time and postoperative hospital stay was significantly shorter in the RIRS than in the mini-PCNL group. The SFR, auxiliary treatment on residual stones, and complications were comparable. In both groups, no major (Clavien IV-V) complications were observed. The mean cost of RIRS was $1210 and $733 for the mini-PCNL.

CONCLUSIONS

Both RIRS and mini-PCNL are effective and safe treatment modalities for pediatric renal stones 10-30 mm in size. However, mini-PCNL is more cost-effective making it a viable alternative to RIRS.

Postoperative outcomes of ureteroscopy for pediatric urolithiasis: A secondary analysis of the National Surgical Quality Improvement Program Pediatric

INTRODUCTION

Incidence of pediatric urinary stone disease (PUSD) has increased over recent decades. Innovations in ureteroscopic technology has expanded the role of endourologic stone management in children. However, there is currently no consensus on the optimal use of ureteroscopy (URS) within the heterogenous PUSD population.

OBJECTIVE

The primary objective was to investigate the rate of 30-day unplanned readmissions in pediatric patients after URS. The secondary objective was to examine the influence of demographic, perioperative, postoperative, and reoperation variables as predictors of an increased risk of unplanned readmission in this sample.

STUDY DESIGN

A secondary analysis was performed on retrospectively collected data from the National Surgical Quality Improvement Program Pediatric between 2015 and 2018. Pediatric patients diagnosed with PUSD and treated with URS were identified. Patients undergoing concurrent or additional surgeries during the URS procedure were excluded. Data on demographic, perioperative, postoperative, and unplanned reoperation variables were examined for their possible influence on 30-day unplanned readmissions. Descriptive statistics were used to characterize the study cohort. Continuous and categorical variables were analyzed using independent samples t-test, one-way ANOVA with Tukey post-hoc test, and Chi-square Tests or Fisher's Exact Test, respectfully. Multivariate analysis was performed using stepwise logistic regression.

RESULTS

A total of 2510 patients were identified within the study period. The majority of children undergoing URS were between 12 and 18 years of age (66.1%), female (56.9%), and had renal calculi (45.2%). Of these, 162 (6.5%) experienced a 30-day unplanned readmission related to the URS procedure. The most common reasons for an unplanned readmission was urinary tract infection (31.4%), new/unresolved stone (28.3%), and postoperative pain (8.2%). Multivariate modelling showed that females (Relative Risk [RR]: 2.03; 95% Confidence Interval [95%CI]: 1.34-3.07), patients with renal stones (RR: 1.77; 95%CI: 1.10-2.83), and inpatients at the time of surgery (RR: 1.61; 95%CI: 1.03-2.51) were more at risk of an unplanned readmission within 30-days of an URS procedure.

CONCLUSION

This study reports on short-term unplanned readmission rates in pediatric patients who underwent an URS procedure. Further it highlights possible predictors of unplanned readmission rates within a sampling of patients from NSQIP affiliated institutions. The findings from this study can be used to guide future studies around the safe use of URS in pediatric patients.

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.

Safety and Outcomes of using ureteric access sheath (UAS) for treatment of Pediatric renal stones: Outcomes from 2 tertiary endourology centers

OBJECTIVE

To look at the safety and outcomes of using ureteral access sheath (UAS) for pediatric renal stones. The use of UAS is variable in urological practice with very little clinical work on their use in pediatric kidney stone disease.

PATIENTS AND METHODS

Data was retrospectively collected from 2 large European tertiary endourology centers for all pediatric patients (≤16 years) with renal stones who underwent flexible ureteroscopy and lasertripsy (FURSL) via UAS. Data was collected on patient details, stone demographics and clinical outcomes of the FURSL procedure.

RESULTS

Forty-eight patients with a mean age of 10.7 years were treated with FURSL for a mean single and cumulative stone size of 10.4 mm and 15 mm respectively, with two-third having multiple stones and stones in the lower pole. The initial and final stone free rate (SFR) was 66.7% and 100% respectively with 1.3 procedures/patient. One patient each had intra-operative grade 1 ureteric injury and post-operative UTI, with no other injuries or complications noted. Over a mean follow-up of 17 months, no other complications were noted.

CONCLUSION

Ureteral access sheath is safe for treatment of pediatric renal stones with excellent outcomes and are especially useful for larger or multiple stones. While there does not seem to be any medium-term sequalae, to avoid risk of ureteral injury, we would suggest using the smallest size sheath possible. We would argue these procedures are best done in specialist high-volume endourology units for optimal results.

Urinary lithiasis - conventional open surgery

The Guidelines Project, an initiative of the Brazilian Medical Association, aims to combine information from the medical field in order to standardize producers to assist the reasoning and decision-making of doctors. The information provided through this project must be assessed and criticized by the physician responsible for the conduct that will be adopted, depending on the conditions and the clinical status of each patient.

Effectiveness of ultrasound-guided shockwave lithotripsy and predictors of its success rate in pediatric population: A report from a national reference center

OBJECTIVE

Shockwave lithotripsy (SWL) remains a well-established treatment modality for many of the pediatric renal and ureteral stones. Repeated SWL sessions carry limitations due to the use of general anesthesia and X-ray radiation. The objective of our study was to evaluate stone-free rate (SFR) of 1-session of SWL for the management of pediatric renal and ureteral stones less than 2 cm performed exclusively under ultrasound guidance and identify factors influencing its success.

METHODS

The study utilized a retrospective cohort design including 124 consecutive pediatric patients with 133 renal and ureteral stones less than 2 cm whom SWL was performed in the period of January 2008 to December 2019. SWL procedures were performed by one expert surgeon in a single, national reference center, exclusively under ultrasound guidance using Modulith® SLK lithotripter. Follow-up was performed in post-SWL 2nd, 4th, 12th weeks and 6 months.

RESULTS

The mean age of the children was 10 years (SD = 6.0) and the mean stone size was 10.4 mm (SD = 3.6 mm). Sedation type of anesthesia was used in 80 patients (64.5%). No major complication was developed, and no ureteral stenting was required in any of the patient following SWL. The SFR following 1-session of SWL was 88.0% at 12-week. Younger age (P = 0.002), sedation type of anesthesia (P = 0.001) and presence of radiolucent stones (P = 0.033) significantly improved post-SWL early stone clearance on univariate analysis, the latter being the only significant factor according to final model (P = 0.031).

CONCLUSIONS

Ultrasound-guided SWL represents a safe and effective method for the management of both renal and ureteral stones in children. The SFR following 1-session of SWL at 12-weeks was achieved in 88.0%, the overall success rate after all SWL sessions reaching 91.7%. A higher success rate was observed in children harboring radiolucent stones.

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.

Prevalence of Vesicoureteral Reflux and Urinary Tract Infection in Children with and without Urolithiasis

Background: Vesicourethral reflux (VUR) is a common urinary tract disorder in children, which may be associated with urolithiasis. Objectives: The current study aimed to investigate vesicoureteral reflux in children with and without urolithiasis. Methods: In this case-control study, 130 children younger than 10 years, with a confirmed diagnosis of urinary tract infection (UTI) are investigated. The demographic information and clinical status of all participants were recorded. Ultrasonography was performed for all children, and they were divided into two groups of 65 subjects based on the results: group 1, children with UTI+stone; and group 2, children with UTI+ non-stone. All children received Voiding Cystourethrogram to evaluate Vesicourethral reflux. Results: The mean age of participants was 7.48 ± 3.2 years, and 68 (52.7%) of them were male. Also, VUR was observed in 33 (25.38%) cases. The frequency of reflux in the UTI + stone group was 21 (32.3%), which was significantly higher than the other group (12 cases, or 18.46%) (P = 0.011). However, the association between UTI and stone (P = 0.3, CC = -0.01) was not significant. Conclusions: This study demonstrated a significant correlation between urinary tract stones and VUR in children with urinary tract infections. It is recommended to investigate the presence of stone or VUR in children suffering from any of the described disorders.

Which is the best treatment of pediatric upper urinary tract stones among extracorporeal shockwave lithotripsy, percutaneous nephrolithotomy and retrograde intrarenal surgery: a systematic review

Background

Although the indications of minimally invasive treatments for pediatric urolithiasis are similar to those in adults, it is still crucial to make the right treatment decision due to the special considerations of children. This review aims to evaluate the efficacy and safety of extracorporeal shockwave lithotripsy (SWL), percutaneous nephrolithotomy (PCNL), and retrograde intrarenal surgery (RIRS) in the management of pediatric upper urinary tract stones.

Methods

EMBASE, PubMed, and the Cochrane Library were searched from their first available date to March 2018. The studies that meet the inclusive criteria were included. The efficacy and safety of the treatments were assessed by means of meta-analysis of the stone free rate (SFR), complication rate, effectiveness quotient (EQ) and secondary outcome indicators.

Results

A total of 13 comparative studies were identified for data analysis. PCNL presented a significantly higher SFR compared with SWL. Similarly, the single-session SFR of RIRS was significantly higher than SWL. However, no significant difference was found between RIRS and SWL in the overall SFR. There was no significant difference between PCNL and RIRS in the SFR. Furthermore, no significant differences in complication rates were found among the three therapies. Compared with the other two treatments, PCNL had a longer operative time, fluoroscopy time and hospital stay. SWL had a shorter hospital stay, higher retreatment rate and auxiliary rate in comparison with the other two treatments. The present data also showed that PCNL presented a higher EQ than the other two treatments, and RIRS had a lower efficiency than SWL and PCNL. In the subgroup analysis of pediatric patients with stone ≤20 mm, the comparative results were similar to those described above, except for the higher complication rate of PCNL than SWL.

Conclusions

Although SWL as an outpatient procedure provides shorter hospital stay and reduces operative time, it has a lower SFR and higher retreatment rate than the other two treatments. PCNL exhibits a higher SFR and EQ than SWL; nevertheless, it has a longer operative time and fluoroscopy time than the other two procedures. RIRS offers a similar SFR as PCNL but a lower efficiency than PCNL.

Interest of URS-L in the Treatment of Ureterolithiasis in Preschool Children

Urolithiasis can affect all children even preschool ones. Diagnostic difficulties in the youngest children are due to the problems in locating pain and determining its character and severity. In keeping with the ALARA (As Low As Reasonably Achievable) protocol, the number of imaging tests possible to perform is very limited. Ultrasound is the first line exam of choice. After diagnosis of the presence of a stone, ESWL (Extracorporeal Shock Wave Lithotrypsy) should always be considered and offered to parents due to its high effectiveness and minimal invasiveness. If ESWL is contraindicated or not well-accepted by parents, authors suggest another minimal invasive approach: URS-L (Uretherorenoscopy-Lithotrypsy). Our study clinically analyzes 87 children, which were treated between 2009 and 2017 using the URS-L procedure. URS-L treatments were performed using Lithoclast until 2009, and after that time, using the holmium laser Ho:YAG. The overall effectiveness of treatments was 93.3%. There was no failure in the access to the stones. A macroscopic hematuria (Clavien-Dindo I grade) was observed through the second post-operative day in 9.2% of treated patients. No urosepsis was observed. Full metabolic evaluation was performed on all patients. Children remained under constant urological and nephrological observation. A recurrence of urolithiasis was observed in 35.6% of the cases. Treating ureteral lithiasis in young infants remains a big challenge. Our series shows that modern minimal invasive techniques used by very experienced pediatric urologists in high volume centers gives excellent results. In most cases, surgery should no longer need to be an option.

Surgical treatment methods of urolithiasis in the pediatric population

Urolithiasis in the pediatric population represents a major challenge associated with both the diagnosis and therapy of the condition. Over the past 25 years, the incidence has increased. The average age of pediatric patients with stones is about 7-8 years and the recurrence rate is 24%-50%. More than 80% of the stones are eliminated spontaneously. The remaining ones require conservative or surgical treatment. Choosing the most appropriate treatment depends on many factors. Surgical procedures in children are the same as in adults. These include extracorporeal shockwave lithotripsy (ESWL), ureterolithotripsy (URSL), retrograde intrarenal surgery (RIRS), percutaneous nephrolithotomy (PCNL) and laparoscopic or open surgery. ESWL is a method of choice for the treatment of stones with a diameter of ≤20 mm located in the upper urinary tract, while PCNL is used in the treatment of deposits ≥1.5 cm located in the upper pole of the kidney, deposits of ≥1.0 cm located in the lower pole of the kidney, as well as hard stones such as cystic or struvite ones. URSL/RIRS is a method for ureteral and renal stones. Open surgery is indicated in cases when anatomical anomalies coexist with urolithiasis, or when the use of PCNL or ESWL is impossible. The ideal procedure should be effective, safe and allow the complete evacuation of the stones after the 1st procedure.

Ultrasound-guided minimally invasive percutaneous nephrolithotomy in the treatment of pediatric patients <6 years: A single-center 10 years' experience

Owing to the fragile kidney and relative small collecting system of pediatric patients, urologists were always reluctant to treat pediatric urolithiasis with PCNL. Here we conduct a study to assess the effectiveness and safety of pediatric patients with renal calculi <6 years.A total of 88 pediatric patients (99 kidney units) <6 years underwent the ultrasound (US)-guided minimally invasive percutaneous nephrolithotomy in our institute from March 2006 to April 2016. The mean age was 30.9 months (range, 7-72 months). The mean stone size was 19.5 mm (range, 10-50 mm). The group included single stone in 35 kidney units, upper ureteral stone in 12 kidney units, multiple stone in 43 kidney units, and staghorn stone in 9 kidney units. The procedure of puncture and dilation were guided by US solely.The mean operation time was 52.3 minutes (range, 15-140 minutes). The mean postoperative length of stay was 6.0 days (3-16 days). Besides, the initial stone free rate (SFR) was 90.9% (90/99) and the final SFR was 96.0% (95/99). The mean hemoglobin drop was 10.9 g/L (range, 1-25 g/L). Postoperative complications occurred in 12 patients including fever in 11 cases and active pleural effusion in 1 case.The US-guided MPCNL is an effective and safety procedure to treat pediatric patients with stone <6 years.

Outcomes of miniaturized percutaneous nephrolitotomy in infants: single centre experience

Objectives:

The present study was aim to evaluate the safety and efficacy of Mini-PNL to treat kidney stones in patients aged <3 years. This is the one of the largest series in the literature in this age group of patients.

Material and methods:

From May 2012 to April 2016, the medical records of 74 infant patients who underwent mini-PNL for renal stones were reviewed retrospectively. All infants were evaluated with the plain abdominal radiograph, urinary ultrasound, non-contrast computerized tomography and/or intravenous urogram. Pre-operative, intraoperative and post-operative data were analyzed.

Results:

A total of 74 infant (42 male, 32 female) with a mean age 21.5±8.2 (10-36) months were included in this study. The mean size of the stones was 22.0±5.9 (14-45) mm. A 17 Fr rigid pediatric nephroscope with a pneumatic intracorporeal lithotripsy were used through 20-22 Fr access sheath. The stone-free rate was 84.7% at 1 month after the operation. Mean operative time was 74.0 (40-140) min. Mean fluoroscopy screening time was as 4.3(3.1-8.6) min. Average hospitalization time was 3.8 (2-9) day. Auxiliary procedures were performed to 11(15.3%) patients (7 extracorporeal shock wave lithotripsy, 3 re- percutaneous nephrolitotomy, 1 retrograde intrarenal surgery). No major complication classified as Clavien IV-V observed in study group.

Conclusions:

Mini-PNL with pneumatic intracorporeal lithotripsy can be performed safely and effectively to manage kidney stones in infants with high stone free rate and low complications.

Retrograde intrarenal surgery in the management of pediatric cystine stones

OBJECTIVE

To investigate the efficacy and safety of retrograde intrarenal surgery (RIRS) in the treatment of pediatric cystine stones.

STUDY DESIGN

Data of the pediatric patients who underwent RIRS for kidney stones were retrospectively evaluated. A total of 14 children with cystine stones managed with RIRS were identified. In addition to the patient demographics and stone characteristics, all retrospectively obtained operative data were evaluated and discussed in detail, with an emphasis on the success and complication rates.

RESULTS

Mean age of the 14 cases was 10.9 ± 2.2 years (range: 7-15). Mean stone size was 13.6 ± 2.4 mm (range: 10-18) (Summary table). Of these stones, four were located in the renal pelvis, three were in the lower, three were in the middle and the remaining four were located in upper calyx. Ureteral access sheath was used in 12 (85.7%) patients. The double-J ureteral stent was placed pre-operatively in one case and was inserted postoperatively in 12 cases. Mean operation time was 38.2 ± 7.2 min (range: 30-50). Complications were observed in two cases: mild ureteral laceration in the first and fever on the second postoperative day in the second patient. All of the patients were stone free on sonographic evaluation at the 4-week follow-up evaluation. Although potassium citrate treatment was initiated in 11 patients, tiopronin treatment was initiated in four patients for recurrence prophylaxis during long-term follow-up. During a mean follow-up period of 25.7 ± 5.2 months, stone recurrence was noted in one patient.

DISCUSSION

Treatment of patients with cystine stones is challenging, due to high risk of rapid recurrence in the presence of residual fragments. Besides allowing complete stone clearance in all cases in the current series, RIRS is a highly reproducible method that can be safely performed, even in recurrences. The major limitations of the current study were low number of patients and short follow-up period.

CONCLUSION

The results clearly indicated that RIRS is a safe treatment modality in the management of pediatric cystine stones.

Paediatric ureterolithotripsy: Tips and tricks - Experience at a single center

BACKGROUND

Paediatric stone disease is very common in certain regions of India. Traditionally, the endourology for the stones even in paediatric age group is managed by adult urologist and paediatric surgeons tend to do open surgeries. The nonavailability of paediatric size equipments and lack of training at the teaching and tertiary care paediatric surgical centers in India are factors due to which there is continued apathy of paediatric surgeons to endourology. The aim of this study was to discuss the feasibility of paediatric ureterolithotripsy for successful procedure. We introduced the paediatric ureterolithotripsy as per the predecided indications of stone size up to 15 mm in paediatric ureterolithiasis at a tertiary care center in rural set up.

SUBJECTS AND METHODS:

Patients up to 18 years of age presenting with ureterolithiasis and not responding to conservative treatment or who needed endourological intervention were included in the study.

RESULTS:

Thirty-one patients underwent uretero lithotripsy (URSL) for ureteric calculus with more than 95% clearance rate.

CONCLUSIONS:

Single-stage paediatric ureterolithotripsy is quite feasible and effective in achieving the stone clearance in paediatric ureterolithiasis.

The primary hyperoxalurias: A practical approach to diagnosis and treatment

Although the primary hyperoxalurias (PH) are rare disorders, they are of considerable clinical importance in relation to calcium oxalate urolithiasis and as a cause of renal failure worldwide. Three distinct disorders have been described at the molecular level. The investigation of any child or adult presenting with urinary tract stones or nephrocalcinosis, must exclude PH as an underlying cause. This paper provides a practical approach to the investigation and diagnosis of PH, indicating the importance of distinguishing between the PH types for the purposes of targeting appropriate therapy. Conservative management is explored and the various transplant options are discussed.

Postural therapy for renal stones in children: A Rolling Stones procedure

INTRODUCTION

Despite many advances, the management of renal stones - especially lower caliceal stones (LCS) - remains a challenge. The gravity-dependent location of the lower calices hinders the spontaneous clearance of fragments, which can be a nidus for future growth and symptomatic recurrence. Currently, there is no standard adjunctive therapy to facilitate fragment passage.

OBJECTIVES

To report the safety and effectiveness of mechanical percussion diuresis and inversion (PDI) therapy for eliminating renal stones in children.

PATIENTS AND METHODS

Since November 2013, children with residual fragments (after shock wave lithotripsy or flexible ureteroscopy) or native symptomatic renal stones were prospectively included in a protocol of four PDI sessions. After giving written consent, the children drank 10 ml/kg of water 30 min before therapy. They then laid in a prone Trendelenburg position on a couch angled at 45° and received continuous 10-min mechanical percussion applied over the affected flank by a physiotherapist (Figure summary). Tolerance stone burden reduction and stone clearance were documented with ultrasound 4 weeks after the last session.

RESULTS

Seventeen participants, with a median age of 10.8 years (range 18 months to 18 years), received 82 PDI sessions performed over 22 months. The median stone diameter was 5 mm (range 3-9). All children tolerated the PDI therapy well. Over a median follow-up of 11 months (range 3-18), no significant adverse effects were noted. The overall stone-free rate was 65%. Four of the six patients with residual fragment passed their fragments. The patients who did not become stone free by PDI experienced a decrease in fragment size of 57% (range 34-71). The observance rate was 100%.

DISCUSSION

Many studies have demonstrated that the gravity-dependent position of the lower calyces appears to be an important factor limiting the clearance of LCS. Positioning patients with a degree of inversion in order to put the collecting system beyond the horizontal plane affected the LCS through gravitational force. Complications were rare. PDI appeared to save costs and have similar success rates as shock wave lithotripsy for native small renal stones in children.

CONCLUSION

PDI is safe and effective for facilitating gravity-dependent drainage of renal stones and provides an opportunity to treat children in a quick, non-invasive, economic, painless, non-radiative and diverting fashion. This therapy is a valuable alternative in the pattern of stone management. In case of persistent fragments, it is recommend that the number of sessions be increased to six.

Outcomes of Shock Wave Lithotripsy and Ureteroscopy for Treatment of Pediatric Urolithiasis

PURPOSE

Shock wave lithotripsy has been commonly used to treat children with renal and ureteral calculi but recently ureteroscopy has been used more frequently. We examined postoperative outcomes from these 2 modalities in children.

MATERIALS AND METHODS

We reviewed linked inpatient, ambulatory surgery and emergency department data from 2007 to 2010 for 5 states to identify pediatric admissions for renal/ureteral calculi treated with shock wave lithotripsy or ureteroscopy. Unplanned readmissions, additional procedures and emergency room visits were extracted. Multivariate logistic regression using generalized estimating equations to adjust for hospital level clustering was performed.

RESULTS

We identified 2,281 admissions (1,087 for shock wave lithotripsy and 1,194 for ureteroscopy). Ages of patients undergoing ureteroscopy and those undergoing shock wave lithotripsy were similar (median 17.0 years for both cohorts, p = 0.001) but patients were more likely to be female (63.4% vs 54.7%, p <0.0001), to be privately insured (69.8% vs 62.2%, p <0.0005) and to have a ureteral stone (81.0% vs 34.8%, p <0.0001). Patients undergoing ureteroscopy demonstrated a lower rate of additional stone related procedures within 12 months (13.6% vs 18.8%, p <0.0007) but a higher rate of readmissions (10.8% vs 6.3%, p <0.0002) and emergency room visits (7.9% vs 4.9%, p <0.0036) within 30 days postoperatively. On multivariable analysis patients undergoing ureteroscopy were nearly twice as likely to visit an emergency room within 30 days of the procedure (OR 1.97, p <0.001) and to be readmitted to inpatient services (OR 1.71, p <0.01).

CONCLUSIONS

Ureteroscopy is now used more commonly than shock wave lithotripsy for initial pediatric stone intervention. Although repeat treatment rates did not differ between procedures, ureteroscopy patients were more likely to be seen at an emergency room or hospitalized within 30 days of the initial procedure.

Mini-percutaneous Nephrolithotomy Under Total Ultrasonography in Patients Aged Less Than 3 Years: A Single-center Initial Experience from China

Background:

Urolithiasis in pediatric population is a serious problem with the incidence increased these years. In the management of larger stones (diameters >2 cm), percutaneous nephrolithotomy (PCNL) is considered to be the gold standard. This study aimed to investigate the efficacy and safety of mini-PCNL under total ultrasonography in patients aged <3 years.

Methods:

We reviewed 68 patients (80 renal units) aged <3 years between August 2006 and December 2014 in Peking University People's Hospital and Beijing Tsinghua Changung Hospital, including 36 renal units with a single stone, 6 with staghorn stones, 14 with upper ureteral stones, and 24 with multiple stones. The mean age of the patients was 24.2 months (range 6–36 months), and the mean maximum stone diameter was 19.2 mm (range 10–35 mm). The puncture site selection and tract dilation were guided by Doppler ultrasonography solely. All procedures were performed using 12–16 Fr tracts. Stones were fragmented using pneumatic lithotripsy and a holmium laser with an 8/9.8 Fr rigid ureteroscope.

Results:

Fifty-six patients with unilateral stones underwent a single session procedure, and 12 patients with bilateral stones underwent two procedures. The mean time to establish access was 2.8 min (range 1.8–5.0 min), the mean operative time was 36.5 min (range 20–88 min), the mean decrease in hemoglobin concentration was 8.9 g/L (2–15 g/L), and the stone-free rate (SFR) at hospital discharge was 94.0%. The mean postoperative hospital stay was 7.1 days (range 3–13 days). Postprocedure complications included fever (>38.5°C) in five patients and reactive pleural effusion in one patient. Blood loss requiring transfusion, sepsis, adjacent organ injury, and kidney loss were not observed.

Conclusions:

This study indicated that ultrasound-guided mini-PCNL is feasible and safe in patients aged <3 years, without major complications or radiation exposure.

[Impact of the acquisition of a flexible ureteroscope on the management of upper urinary tract stones in children]

INTRODUCTION

Firstly reported in the early 1990s for the treatment of upper urinary tract stones in adult patients, flexible ureteroscopy (F-URS) has been used in children during the past 10 years and is now considered as a viable, but still second-line alternative to extracorporeal shockwave lithotripsy in these patients (ESWL). The aim of this study was to assess the impact of the acquisition of a F-URS on the management of upper urinary tract stones in children.

PATIENTS AND METHODS

Data of all ESWL, F-URS and percutaneous nephrolithotomy performed for upper urinary tract stones in children from 0 to 18 years old in a single center from 2000 to 2014 have been collected retrospectively. Patients have been divided into two groups: group 1 before the acquisition of the F-URS (2000-2008) and group 2 after the acquisition of the F-URS (2008-2014). Preoperative data and peri-operative outcomes were compared between both groups using the χ(2) test and Fisher exact test for discrete variables and the Mann-Whitney test for continuous variables.

RESULTS

Thirty-seven children have been treated during the first era and 32 during the second one. The two groups were similar in terms of age (7.2 years vs 8.1 years; P=0.54), size of the largest stone (15 mm vs 16.2mm; P=0,56) and number of stones per patient (1.4 vs 2; P=0,07) but the sum of stone diameters was higher in group 2 (16.9 mm vs 24.2mm; P=0,048). The stone-free rates were comparable in both groups (28.1% vs 32.2% after the first procedure; P=0.72), as were the mean number of procedures per patient (2.4 vs 2.5; P=0.78), the total length of stay (2.7 days vs 2.9 days; P=0.77), and the number of patients who experienced at least one complication (37.8% vs 40.6%; P=0.87).

CONCLUSION

The acquisition of a F-URS allowed the treatment of more complex stones with a similar efficacy and without increasing morbidity. Further studies are needed to define the role of F-URS in the management of upper urinary tract stones in children.

Ultrasound-guided mini-percutaneous nephrolithotomy in patients aged less than 3 years: the largest reported single-center experience in China

To investigate the efficacy and safety of mini-percutaneous nephrolithotomy (mini-PCNL) under total ultrasonography in patients aged <3 years.

METHODS

We reviewed 56 patients (67 renal units) aged <3 years between August 2006 and December 2012 in our units, including 31 renal units with a single stone, 6 with staghorn stones, 10 with upper ureteral stones, and 20 with multiple stones. The mean age of the patients was 24 (range 6-36) months and the mean maximum stone diameter was 18.9 (range 10-32) mm. The puncture site selection and tract dilation were guided by Doppler ultrasonography solely. All procedures were performed using 12-16 Fr tracts. Stones were fragmented using pneumatic lithotripsy and a holmium laser with an 8/9.8 Fr rigid ureteroscope. Forty-five patients with unilateral stones underwent a single procedure, and 11 patients with bilateral stones underwent two procedures. The mean time to establish access was 2.9 (range 2.1-5) min, the mean operative time was 36.8 (range 20-88) min, the mean decrease in hemoglobin concentration was 8.7 (2-15) g/L, and the stone-free rate at hospital discharge was 92.5%. The mean postoperative hospital stay was 7.1 (range 3-13) days. Post-procedure complications included fever (>38.5 °C) in four patients, and reactive pleural effusion in one patient. Blood loss requiring transfusion, sepsis, adjacent organ injury, and kidney loss were not observed. Ultrasound-guided mini-PCNL is feasible and safe in patients aged <3 years, without major complications or radiation exposure.

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.

FT-IR spectroscopic, thermal analysis of human urinary stones and their characterization

In the present study, FT-IR, XRD, TGA-DTA spectral methods have been used to investigate the chemical compositions of urinary calculi. Multi-components of urinary calculi such as calcium oxalate, hydroxyl apatite, struvite and uric acid have been studied. The chemical compounds are identified by FT-IR spectroscopic technique. The mineral identification was confirmed by powder X-ray diffraction patterns as compared with JCPDS reported values. Thermal analysis techniques are considered the best techniques for the characterization and detection of endothermic and exothermic behaviors of the urinary stones. The percentages of each hydrate (COM and COD) are present together, in the presences of MAPH or UA. Finally, the present study suggests that the Urolithiasis is significant health problem in children, and is very common in some parts of the world, especially in India. So that present study is so useful and helpful to the scientific community for identification of latest human health problems and their remedies using spectroscopic techniques.

Treatment alternatives for urinary system stone disease in preschool aged children: results of 616 cases

INTRODUCTION

The treatment of stone disease is mostly similar in those adult and children. The standard treatment procedures are as follows: extracorporeal shock wave lithotripsy (ESWL), ureterorenoscopy (URS), percutaneous nephrolithotomy (PCNL), and laparoscopic surgery in selected cases. Open surgery (OS) is another option particularly in such cases with anatomic abnormalities of urinary tract.

OBJECTIVE

The present study aims to provide comparative results of stone removal procedures in preschool aged patients who were diagnosed with urinary system stone disease.

STUDY DESIGN

The retrospective data of 616 pediatric preschool patients consulted with urinary system stone disease between January 2009 and July 2013 were evaluated. All patients were evaluated with Kidney-Ureter-Bladder (KUB) Xray and abdomino-pelvic ultrasound. Intravenous pyelography, unenhanced computed tomography (CT), and renal scintigraphy were performed when needed. Patients were categorized according to the procedures as: Group ESWL, Group URS, Group PNL, Group micro-PNL and Group OS. Following the procedures, opaque residual stones were evaluated with KUB Xray, and non-opaque residual stones were evaluated with unenhanced CT.

RESULTS

In groups (ESWL, URS, PNL, micro-PNL, OS), the stone-free rate was 68%, 66%, 85%, 100% and 94 %, respectively. The stone analysis were observed as, calcium oxalate in 377 patients (61.2%), uric acid in 106 patients (17.2%), infection stone in 73 patients (11.8 %), and cysteine in 60 patients (9.7%). There was no significant difference in stone analysis between the groups (p > 0.05) (Table).

DISCUSSION

Minimally invasive procedures are frequently preferred in the pediatric age urinary system stone disease. These procedures are ESWL, PCNL, and ureteroscopy [10,11]. Open surgery is reserved only for rare cases [12]. Similarly the current literature, 18 (2.9%) patients had anatomical anomaly and had high complex stone burden were treated with open surgery in our study. ESWL is a preferred treatment method for pediatric urolithiasis patients with a stone size <20 mm, and the rate of stone-free after ESWL ranges between 57 and 92% [13]. In a study showed the effect of stone size on the success rate in ESWL, the success rate was 91% for stones <10 mm, and 75% for stones >10 mm [15]. In the present study, stone-free rate was noted as 68% on 15 mm or lower stone size. PNL is commonly used to treat stone disease in preschool children [18-20]. In the beginning, urologists hesitated to use instruments suited for adults in case of pediatric kidneys. While some authors accept a cut-off value of 24 F for tract dilatation in the pediatric age, Desai et al. recommended a threshold value <22 F [19,21]. In our study, we used adult PNL instruments in the early period, whereas mini-PERC was performed in the later years. The success rate in PNL group was found as 85%. In recent years, the micro-PNL procedure has been developed to reduce/prevent the complications of standard PNL. In our study, the success rate was calculated as 100% with micro-PNL. This study has certain limitations. The major limitation of our study is its retrospective nature. In addition, sample size of micro-PNL group is fewer than other groups.

CONCLUSION

The goal of kidney stone treatment is to achieve minimal kidney damage and a high success rate. Thus, the procedures are important in the pediatric age group where life expectancy is high, and particularly in the preschool age group.

Rigid ureteroscopy in children: Our experience

Aim:

To report our experience of Pediatric ureterorenoscopy for ureteric calculi from two tertiary Pediatric urology centers at Apollo Children's Hospital, Chennai and Indraprastha Apollo Hospital, New Delhi.

Material and methods:

All children who presented with symptomatic ureteric stones greater than 6 mm were entered into the study. All children less than 12 months and more than 18 years of age and those who underwent ureterorenoscopy for indications other than the stones were excluded from the study. The children were managed on a fixed investigative and treatment protocol. The data from the Apollo Hospital New Delhi and Apollo Children's Hospital Chennai was analysed.

Results:

There were a total of thirty eight children, twenty in Chennai and eighteen in the New Delhi study. The mean age was 10.4 years and 8.5 years and the youngest child was14 months and 24 months in the Chennai and New Delhi group respectively. There was one conversion to open surgery in either group. Pneumatic lithotripter was used in majority of cases and holmium laser in select children.

Conclusion:

This is the largest Indian series of ureterorenoscopy for ureteric calculi in children. This study over nearly a decade confirms the safety and efficacy of this technique even in young children. In children less than five years, prestenting and delayed ureterorenoscopy allows safe endoscopic treatment of ureteric calculi.

Minipercutaneous nephrolithotomy in infants: a single-center experience in an endemic region in Turkey

The objective of the study is to evaluate the effectiveness and safety of miniaturized percutaneous nephrolithotomy (mini-PNL) method in infantile patients <3 years of age diagnosed with renal stones. We studied 48 renal units in 40 patients of infantile patients <3 years of age who underwent mini-PCNL at our institute. The mean age of the patients was 24.02 (5-36) months. The mean diameter of the stones was 22.3 mm (11-45 mm). Intrarenal access was achieved under fluoroscopic (n = 43) or ultrasonographic (n = 5) guidance under general anesthesia. A 20 Fr peel-away sheath, a 17 Fr rigid nephroscope and a pneumatic intracorporeal lithotripsy were used. Mean operative time for PNL was 85 (25-135) min. Mean fluoroscopy time was estimated as 3.7 min. The mean hospital stay was 4.3 days (2-10). Mean hemoglobin loss was 0.89 g/L (11.56-10.67) and three of the patients, including one case during the perioperative period, required blood transfusions. Colonic perforation developed in one case. In two patients, urinary drainage persisted for more than 24 h after withdrawal of the nephrostomy tube. Seven patients developed urinary tract infections (UTI). At the end of the postoperative first week, the stone-free rate was estimated to be 81.2 %. In conclusion, for percutaneous management of renal stones in the infantile age group, mini-PNL is an applicable treatment modality that can be applied through small incisions. It has higher stone-free rates, shorter hospital stays, and excellent esthetic outcomes. In this age group especially, surgical exposure to hypothermia and radiation should be avoided.

High incidence of urinary stones in Uyghur children may be related to local environmental factors

OBJECTIVE

To analyze the causes of urolithiasis in Uyghur children from Xinjiang.

PATIENTS AND METHODS

We retrospectively evaluated the clinical features and characteristics of urinary stone composition of 220 Uyghur pediatric patients with urolithiasis between March 2009 and June 2011. The data were compared with that of 100 Uyghur children without urolithiasis who visited the Child Care Clinic for regular health check-ups. The stones were collected by endoscopy or open surgery, and analyzed using infrared spectroscopy.

RESULTS

The mean age of the 220 Uyghur children was 7.48 ± 4.73 years (range, 0.8-17.0 years). The overall sex ratio (male:female) was 2.23:1. The predominant pure stone was ammonium urate (58.9%), whereas the predominant mixed stone was calcium oxalate mixture (91.1%). Uric acid stones comprised 54% of all stones. Urinary tract infections were observed in 42.3% and 4.0% of the patient and control groups, respectively. The mean urinary pH values were 5.77 ± 0.67 and 6.42 ± 0.67, respectively (p < 0.001). pH values were <5.5 in 52.7% and 6% of the patient and control groups, respectively. On 24-h urine analysis, we found metabolic disturbances in these patients: hypercalciuria in 6.8% cases, hyperphosphaturia in 16.8% cases, hyperuricosuria in 21.4% cases, and hypomagnesiuria in 34.1% cases.

CONCLUSIONS

Urolithiasis in Uyghur children may be primarily related to local environmental factors.

Retrograde intrarenal surgery monotherapy versus shock wave lithotripsy for stones 10 to 20 mm in preschool children: a prospective, randomized study

PURPOSE

We compared the outcome of retrograde intrarenal surgery monotherapy vs shock wave lithotripsy for stones 10 to 20 mm in preschool children.

MATERIALS AND METHODS

This prospective study included 60 children with a mean ± SD age of 2.4 ± 1.3 years. Patients were randomly divided into 2 groups. Group 1 underwent shock wave lithotripsy and group 2 underwent retrograde intrarenal surgery as monotherapy. Retrograde intrarenal surgery was started using a 7.5Fr semirigid ureteroscope (Storz®) and the holmium laser, and completed by the Flex X™2 flexible ureterorenoscope. A ureteral access sheath was not used and only hydrodilatation was performed. Patients were evaluated preoperatively by ultrasound and plain abdominopelvic x-ray. Followup was 3 months.

RESULTS

The stone-free rate after a single session treatment was 70% and 86.6% in groups 1 and 2, respectively. Mean operative time was 27.9 ± 3.5 and 40 ± 7.8 minutes, mean fluoroscopy exposure time was 60 ± 42 and 50 ± 35 seconds, and mean hospital stay was 6 ± 2 and 12 ± 8 hours, respectively. No major complication occurred in either group and no child in either group received blood transfusion. Nine group 1 patients needed a second shock wave lithotripsy session, of whom 2 required a third session. At 3 months the overall stone-free rate was 93.3% and 96.6% in groups 1 and 2, respectively.

CONCLUSIONS

Retrograde intrarenal surgery is an option for treating medium sized renal stones in preschool children with results comparable to those of shock wave lithotripsy and a safe short-term outcome.

Recent management of urinary stone disease in a pediatric population

The incidence of stone disease has been increasing and the risk of recurrent stone formation is high in a pediatric population. It is crucial to use the most effective method with the primary goal of complete stone removal to prevent recurrence from residual fragments. While extracorporeal shock wave lithotripsy (ESWL) is still considered first line therapy in many clinics for urinary tract stones in children, endoscopic techniques are widely preferred due to miniaturization of instruments and evolution of surgical techniques. The standard procedures to treat urinary stone disease in children are the same as those used in an adult population. These include ESWL, ureterorenoscopy, percutaneous nephrolithotomy (standard PCNL or mini-perc), laparoscopic and open surgery. ESWL is currently the procedure of choice for treating most upper urinary tract calculi in a pediatric population. In recent years, endourological management of pediatric urinary stone disease is preferred in many centers with increasing experience in endourological techniques and decreasing sizes of surgical equipment. The management of pediatric stone disease has evolved with improvements in the technique and a decrease in the size of surgical instruments. Recently, endoscopic methods have been safely and effectively used in children with minor complications. In this review, we aim to summarize the recent management of urolithiasis in children.

Extracorporal shock wave lithotripsy in the management of stones in children with oxalosis--still the first choice?

BACKGROUND

Primary hyperoxaluria (PH) is a recognised cause of nephrolithiasis. The aim of this study was to evaluate the success of extracorporal shock wave lithotripsy (ESWL) in treating nephrolithiasis in children with PH.

METHODS

This was a retrospective review of patient characteristics, treatments and outcomes of 36 children with oxalate stones due to PH.

RESULTS

A total of 52 stones were formed in 28 patients, of which 23 stones were treated with ESWL. Of these 23 stones, ten improved and 13 did not; nine were located in the upper pole, nine in the lower pole and four and one in the pelvic and ureteric areas, respectively. All pelvic and ureteric stones improved, while 66.7 % of upper pole stones and 89.9 % of lower pole stones did not; 20 % of PH type 1 stones improved compared to 47 % of PH type 2 stones. The mean pre- and post-eGFR in stone-improvers was 98.82 and 104.7 ml/min/1.73 m(2), respectively; in the non-improvers, these values were 100.75 and 95.68 ml/min/1.73 m(2), respectively. Mean pre-ESWL stone size in the improved and non-improved groups was 7.3 mm and 8.5 mm respectively.

CONCLUSIONS

Based on our results, ESWL is not the ideal method of stone therapy for patients with PH. ESWL was more effective in treating pelvic and ureteric stones, with upper pole stone response being better than lower pole response. PH2 patients were more than twice as likely to respond to ESWL treatment. Stone size and prior preventive treatment did not affect outcome. eGFR was not affected by ESWL.

Are small residual stone fragments really insignificant in children?

OBJECTIVES

To assess the significance of asymptomatic residual stone fragments of less than 4mm (clinically insignificant residual fragments [CIRFs]) after shock wave lithotripsy (SWL), percutaneous nephrolithotomy (PNL), and retrograde intrarenal surgery (RIRS) in children.

PATIENTS AND METHODS

Eighty-five children were followed up for 6 to 50months (median 22). Outcomes measured were fragment re-growth, stone events (emergency department visits, hospitalization, or additional interventions) and spontaneous fragment passage.

RESULTS

During follow-up, 22 children (25.8%) passed residual fragments spontaneously. Highest spontaneous passage rate was found for renal pelvis stones and the lowest for the lower pole stones (57.1% vs. 16.1%; p<0.001). When the number of the fragments increased, the chance of the spontaneous passage decreased (30% vs 20%; p<0.05). Symptomatic episodes including renal colic, hematuria, or urinary tract infection were documented in 34 (40%) patients, and re-growth of fragments was observed in 18 (21.2%). Stone size had no significant effect on spontaneous passage (p=0.079), stone growth (p=0.528), and symptomatic episodes (p=0.402). Twenty-five patients (29.4%) required secondary intervention for stone re-growth or stone related events and the remaining 20 patients (23.5%) needed medical treatment for bothersome symptoms or complications.

CONCLUSIONS

Our results suggest that 40% of children with CIRFs will become symptomatic and 20% will develop stone re-growth over the following 6months. Only one fifth of the fragments will pass spontaneously without any complications. Therefore, the use of the term "CIRF" is not appropriate for postoperative residual fragments in children.

Indication to open anatrophic nephrolithotomy in the twenty-first century: a case report

Introduction. Advances in endourology have greatly reduced indications to open surgery in the treatment of staghorn kidney stones. Nevertheless in our experience, open surgery still represents the treatment of choice in rare cases. Case Report. A 71-year-old morbidly obese female patient complaining about occasional left flank pain, and recurrent cystitis for many years, presented bilateral staghorn kidney stones. Comorbidities were obesity (BMI 36.2), hypertension, type II diabetes, and chronic obstructive pulmunary disease (COPD) hyperlipidemia. Due to these comorbidities, endoscopic and laparoscopic approaches were not indicated. We offered the patient staged open anatrophic nephrolithotomy. Results. Operative time was 180 minutes. Blood loss was 500 cc. requiring one unit of packed red blood cells. Hospital stay was 7 days. The renal function was unaffected based on preoperative and postoperative serum creatinine levels. Stone-free status of the left kidney was confirmed after surgery with CT scan. Conclusions. Open surgery can represent a valid alterative in the treatment of staghorn kidney stones of very selected cases. A discussion of the current indications in the twenty-first century is presented.

Primary hyperoxaluria Type 1: indications for screening and guidance for diagnosis and treatment

Primary hyperoxaluria Type 1 is a rare autosomal recessive inborn error of glyoxylate metabolism, caused by a deficiency of the liver-specific enzyme alanine:glyoxylate aminotransferase. The disorder results in overproduction and excessive urinary excretion of oxalate, causing recurrent urolithiasis and nephrocalcinosis. As glomerular filtration rate declines due to progressive renal involvement, oxalate accumulates leading to systemic oxalosis. The diagnosis is based on clinical and sonographic findings, urine oxalate assessment, enzymology and/or DNA analysis. Early initiation of conservative treatment (high fluid intake, pyridoxine, inhibitors of calcium oxalate crystallization) aims at maintaining renal function. In chronic kidney disease Stages 4 and 5, the best outcomes to date were achieved with combined liver-kidney transplantation.

Comparative analyses of percutaneous nephrolithotomy versus open surgery in pediatric urinary stone disease

PURPOSE

The aim of this study is to compare the efficiency and reliability of percutaneous nephrolithotomy (PCNL) and open surgery for pediatric urinary stone disease.

METHODS

The retrospective analysis included 116 patients (69 PCNL, 47 open stone surgery). The stone surface area, stone-free rates, hospitalization time, blood transfusion rates, and the D-J implantation rates of patients in each group in whom PCNL and open surgery were performed were analyzed.

RESULTS

The average age of the patients in the PCNL group was 10.01 ± 0.51 years, and in the open surgery group 8.55 ± 0.68 years. No statistically significant difference was observed between the two groups in average age, stone surface area or stone-free rates. However, hospitalization time (PCNL 2.31 ± 0.46 days, open surgery 3.36 ± 0.64 days), blood transfusion rate (PCNL 10.1 %, open surgery 42.5 %) and D-J catheter implantation rate (PNL 7.24 %, open surgery 42.5 %) of patients who underwent PCNL were determined to be statistically low.

CONCLUSION

In light of the results, it is concluded that PCNL supersedes open surgery in terms of the use of advanced instruments and technological developments for modern pediatric surgery.

Nonvascular Pediatric Interventional Radiology

Interventional radiology procedures are increasingly in demand in both the adult and pediatric populations. Pediatric procedures mirror many of the adult procedures but with increased complexity due to considerations related to patient size and the requirements for sedation and radiation protection. This article reviews the various nonvascular pediatric interventional procedures and provides information on sedation and radiation protection. The aim is to provide a greater exposure to the possible treatment options for pediatric patients and to facilitate understanding of imaging after various interventions.

Comparison of retrograde intrarenal surgery and mini-percutaneous nephrolithotomy in children with moderate-size kidney stones: results of multi-institutional analysis

OBJECTIVE

To compare the outcomes of miniaturized percutaneous nephrolithotomy (mini-perc) and retrograde intrarenal surgery (RIRS) in children for 10- to 30-mm renal calculi by evaluating operative data, stone-free rates, and associated complications.

METHODS

The records of 201 pediatric patients who underwent mini-perc (n = 106) or RIRS (n = 95) for intrarenal stones of 10- to 30-mm size were reviewed retrospectively. The χ(2) test was applied to compare the success rates, postoperative complications, and blood transfusion rates, and the Mann-Whitney U test was used to compare the means of hospital stay, fluoroscopy, and operative time for mini-perc and RIRS.

RESULTS

The stone-free rate was 84.2% for the RIRS group and 85.8% for the mini-perc group after a single procedure (P = .745). These percentages increased to 92.6% and 94.3% with adjunctive therapies for RIRS and mini-perc, respectively. Minor complications classified as Clavien I or II occurred in 17% and 8.4% in mini-perc and RIRS, respectively. No major complications (Clavien III-V) occurred in either group. Overall complication rates in mini-perc were higher, but the differences were not statistically significant (P = .07). However, 7 patients in the mini-perc group received blood transfusions, whereas none of the children in the RIRS group were transfused (P = .015). The mean hospital stay, fluoroscopy, and operation times were significantly longer in the mini-perc group.

CONCLUSION

This study demonstrates that RIRS is an effective alternative to mini-perc in pediatric patients with intermediate-sized renal stones. Operative time, radiation exposure, hospital stay, and morbidities of percutaneous nephrolithotomy (PNL) can be significantly reduced with the RIRS technique.

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.