Percutaneous nephrolithotomy in infants and preschool age children: experience with a new technique

Is percutaneous nephrolithotomy effective and safe in infants younger than 2 Years old? Comparison of mini standard percutaneous nephrolithotomy

BACKGROUND

In this study, we aimed to compare the operative outcomes, postoperative outcomes, stone-free status and complications of SPCNL and MPCNL in infants younger than two years of age.

METHODS

We retrospectively analyzed 163 patients younger than two years of age who underwent percutaneous nephrolithotomy (PCNL) in our institution between September 1999 and March 2022. The patients were divided into two groups depending on the tract size. The MPCNL group consisted of 73 patients with a tract of 22 Fr or less, and the SPCNL consisted of 90 patients with a tract greater than 22 Fr.

RESULTS

The median age of 163 patients included in the study was 17.3 (range 7-24) months. Although the median stone size was lower in the SPCNL group, no statistically significant difference was found between the two groups in terms of stone size (p = 0.073). The median operative time was 74.8 min in the MPCNL group and 62.8 min in the SPCNL group, with a statistically significant difference (p = 0.002). Stone free rates (SFR) were 89 % and 90.8 % in the MPCNL and SPCNL groups, and the clinically insignificant residual fragments (CIRF) rates were 11 % and 4.6 %, respectively (p = 0.064). The fluoroscopy time, nephrostomy withdrawal time, and hospitalization stay were similar in the two PCNL groups (p = 0.535, p = 0.253, and p = 0.143, respectively). Postoperative fever was similar in MPCNL and SPCNL groups (p = 0.504). Although bleeding (6.7%-2.7 %) and blood transfusion (3.3%-1.4 %) rates were higher in the SPCNL group, there was no statistically significant difference (p = 0.248 and p = 0.420, respectively). Prolonged urinary leakage occurred in 6 (8.2 %) patients in the MPCNL group and 1 (1.1 %) patient in the SPCNL group, with a statistically significant difference (p = 0.026).

CONCLUSIONS

With the development of MPCNL, the use of SPCNL in infants has decreased considerably. However, SPCNL continues to be an effective and reliable method when needed in suitable patients. Although PCNL in infants shows some differences from adults, it is an effective and safe method for suitable patients.

LEVEL OF EVIDENCE

Although we created our study by retrospectively examining the pediatric urology data that we created prospectively, our study is of a retrospective nature. Therefore the Level of Evidence is 3.

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.

Comparison of supine-prone percutaneous nephrolithotomy methods in the treatment of kidney stones in pediatric patients: prospective randomized study

Mini-PCNL is one of the most effective surgical methods in the treatment of kidney stones in pediatric patients. In this study, we aimed to compare PCNL in the supine-prone position in pediatric patients (especially operation time, postop complications, hospital stay and stone-free rates).We conducted our study in a randomized and prospective manner. Patients with lower pole stones larger than 1 cm, stones larger than 1.5 cm in the pelvis, upper pole, midpole or multiple locations, and patients who did not respond to ESWL or whose family that preferred mini-PCNL to be the primary treatment were included in the study. Patients with any previous kidney stone surgery, patients with coagulation disorders and patients with retrorenal colon were excluded from the study. Between 2021 and 2023, a total of 144 patients underwent PCNL. 68 of these patients had supine PCNL and 76 prone PCNL. Postoperative Clavien grade1 complication occurred in a total of 7 patients in the prone position; Clavien grade1 complication occurred in 1 patient in the supine position. The mean operation time for prone PCNL was 119.88 ± 28.32 min, and the mean operative time for supine PCNL was 98.12 ± 14.97 the mean hospitalization time in prone PCNL was 3.56 ± 1.12 days, and 3.00 ± 0.85 days in supine PCNL. In conclusion, supine PCNL is a safe and effective method in the treatment of pediatric kidney stones and postoperative complications were observed to be less; the operation time and hospital stay were shorter in supine PCNL.

A retrospective cohort study: evaluating the efficacy of standard versus tubeless percutaneous nephrolithotomy (PCNL) in pediatric patients up to 18 years old

Percutaneous nephrolithotomy (PCNL) is an endourological method applied as the standard or tubeless method for kidney stone treatment. In a retrospective cohort study, 88 surgery units involving 75 children up to 18 years old with kidney stones who underwent the surgery for 8 years in Shahid Beheshti and Boo-ali hospitals in Hamadan with one of the two methods of standard or tubeless PCNL were evaluated and compared considering the success rate of operation, hemoglobin, hematocrit drop, need for medications, need for blood transfusion, duration of surgery, and the length of hospital stay. Among the 88 units studied, 47 cases were operated with the standard PCNL and 41 cases by tubeless method. In children operated by standard and tubeless PCNL, the complete success rate of operation was 87.2% and 100% (P = 0.006), the need for blood transfusion was 2.1% and 0% (P = 1.00), the need for opioids was 27.7% and 14.6% (P = 0.134), the decrease in hemoglobin was - 1.82 ± 0.94 and -1.30 ± 0.98 mg/dl (P = 0.024), the decrease in hematocrit was - 5.40 ± 2.66 and -3.52 ± 3.11 mg/dL (P = 0.003), the mean surgery duration was 109.30 ± 53.27 and 101.46 ± 31.92 min (P = 0.414), the duration of postoperative hospitalization was 3.38 ± 1.76 and 2.46 ± 1.27 days (P = 0.007), and the frequency of fever was 23.4% and 7.3% (P = 0.04), respectively. The success rate of kidney stone surgery in children with the tubeless PCNL is higher than the standard method, and its complications are lower.

Vacuum-assisted Mini-percutaneous Nephrolithotomy for 2-3-cm Renal Stones: A Comparative Study with Retrograde Intra-renal Surgery

PURPOSE

To compare vacuum-assisted percutaneous nephrolithotomy (VAmini-PCNL) with retrograde intra-renal surgery (RIRS) for the treatment of renal stones measuring 2-3 cm in diameter.

MATERIAL AND METHODS

This retrospective study included children receiving treatment for pyelocalyceal stones of 2-3 cm in diameter from November 2018 to September 2022. Consecutive patients undergoing VAmini-PCNL after 2020 were compared with a historically matched group undergoing RIRS. VAmini-PCNL was performed using a 12-Ch nephroscope through a 16-Ch vacuum ClearPetra access sheet. RIRS was performed using a flexible ureteroscope through a ureteral sheath. The endpoints included the need for pre-stenting, duration of surgery, complications, stone-free rate (SFR), and need for secondary procedures.

RESULTS

The patients were grouped into two with 15 patients for each group. VAmini-PCNL group was not different from the RIRS one for age at surgery [median (range) 6.6 (1-12)years vs. 7.7 (1.5-14)years], and stone diameter [median (range) 2.4 (2.0-2.9)cm vs. 2.3 (2.1-2.8)cm] and density [median (range) 577.5 (421-1068) vs. 541.5 (462-927) Hunsfield Units]. Pre-stenting was necessary in five RIRS patients (33 %). The median duration of surgery was 85.3 (76-112)min for VAmini-PCNL vs. 150.6 (132-167)min for RIRS, p = 0.00001. No major complications were observed. The SFR was 100 % after VAmini-PCNL and 60 % after RIRS, p = 0.02. All residual fragments were removed with a second RIRS.

CONCLUSION

VAmini-PCNL was feasible and safe in children aged >1 year. It allowed for a significantly higher SFR despite a significantly shorter operative time than RIRS, which also requires pre-stenting in one-third of patients and a second RIRS in 40 % of cases.

LEVEL OF EVIDENCE

III.

Comparison of Two Centers' Experience in Pediatric Supine and Prone Miniaturized Percutaneous Nephrolithotomy with Propensity Match Analysis

Introduction: Percutaneous nephrolithotomy (PNL) is the treatment of choice in children with complex and large stones. With the experience gained from adult practice, supine PNL is increasingly performed in children as well. We aimed to evaluate the comparative results of prone and supine mini-PNL (m-PNL) performed for large/complex stones in children. Patients and Methods: The study included children who underwent supine and prone m-PNL at two centers between September 2019 and 2022. Patients were divided into two groups with a 1:1 ratio to index supine m-PNL and prone m-PNL cases for the size, number, location of the stones, degree of hydronephrosis, and age. Operative related parameters, success, and complication rates are being discussed on a procedure-based manner. Results: Forty-two patients (21 supine and 21 prone) were included. The mean age was 9.6 ± 4 years and mean stone size was 28.8 ± 13.6 mm. Regarding the operative data, the mean duration of procedure time was 65.7 ± 17.8 minutes in supine group, whereas 86.9 ± 19.0 minutes in prone group (p = 0.001). Fluoroscopy time was shorter in supine group (p = 0.027). Tubeless PNL was performed in 11 cases of prone group (52%), whereas this number was 18 (86.7%) in supine group (p = 0.019). Stone-free rates were similar in both groups (supine m-PNL: 90.5%, prone m-PNL: 85.7%, p = 0.634). Complications were minor in nature in most of the cases of both groups, which resolved with supportive measures in a short period of time. However, there was a statistically significant difference regarding the location and number accesses between two groups (p = 0.008). Simultaneous flexible ureterorenoscopy was performed in eight patients in the supine PNL group (<0.001). Conclusions: Our current findings and the highly limited data reported in the literature indicate that as an established minimal invasive treatment alternative m-PNL procedure in supine position can also be performed with similar success and complication rates in pediatric population.

Mini-versus standard percutaneous nephrolithotomy in pediatric population: A randomized controlled trial

INTRODUCTION

Mini PCNL has gained popularity in adult patients due to reduction in the complication rate with comparable stone free rate. There is paucity of level 1 evidence regarding the benefit of mini PCNL in the pediatric group.

OBJECTIVE

We performed a randomised study to compare mini PCNL (mPCNL) with standard PCNL (sPCNL) for the management of renal calculi in patients less than 18 years of age in terms of safety, efficacy, and stone-free rate (SFR).

MATERIALS AND METHODS

A randomised controlled trial was performed on 50 children who underwent PCNL from June 2015 to March 2021, who were divided into two groups. Group I had 25 patients managed with mPCNL (sheath size 16.5 Fr) and Group II had 25 patients who underwent sPCNL (sheath size 26 Fr). Primary outcomes including stone free rates (SFR) and hemoglobin drop and secondary outcomes like operative time, complications, pain score, need of analgesia, incidence of nephrostomy site leak, hospital stay in days were compared between the two groups.

RESULTS

The mean age of patients in groups I and II was 9.4 ± 2.6 and 10.4 ± 2.26 years, respectively (p = 0.15). The mean stone sizes in both groups I and II were 18.6 ± 2.56 and 20.2 ± 3.58 mm, respectively (p > 0.05). The stone free rate for group I was 88% and for group II, 92% (p = 0.64). The average drop in hemoglobin was higher in group II compared to group I (1.1 ± 0.31 g/dl and 1.7 ± 0.23 g/dl respectively; p < 0.0001), however the mean blood transfusion rate was not significantly different in both groups. The operating time was shorter in group II compared to group I (p-value - 0.0030). The pain scores were lesser for the group I. Grade I complications were higher in group II as compared to group I (p-0.047); however, grade II complications were comparable in both groups. The mean hospital stay was not significantly different in both groups.

DISCUSSION

This study confirms the role of mini PCNL in pediatric patients with renal stones. The stone clearance rate of mini PCNL is equivalent to standard PCNL, with lesser blood loss and postoperative complications, however with longer operative time during mPCNL. The small number of the participants in both arms is a limitation of this study and may also reflect fewer children with urolithiasis being treated surgically even in a tertiary care referral centre.

CONCLUSIONS

Mini-PCNL offers equivalent stone free outcome with lower complications rate compared to the standard PCNL for all types of renal stones.

Percutaneous nephrolithotomy versus retrograde intrarenal surgery for treatment of renal stones in adults

BACKGROUND

Kidney stones (also called renal stones) can be a source of pain, obstruction, and infection. Depending on size, location, composition, and other patient factors, the treatment of kidney stones can involve observation, shock wave lithotripsy, retrograde intrarenal surgery (RIRS; i.e. ureteroscopic approaches), percutaneous nephrolithotomy (PCNL), or a combination of these approaches.

OBJECTIVES

To assess the effects of percutaneous nephrolithotomy (PCNL) versus retrograde intrarenal surgery (RIRS) for the treatment of renal stones in adults.

SEARCH METHODS

We performed a comprehensive search of the Cochrane Library, MEDLINE, Embase, Scopus, and two trials registries up to 23 March 2023. We applied no restrictions on publication language or status.

SELECTION CRITERIA

We included randomized controlled trials that evaluated PCNL (grouped by access size in French gauge [Fr] into three groups: ≥ 24 Fr [standard PCNL], 15-23 Fr [mini-PCNL and minimally invasive PCNL], and < 15 Fr [ultra-mini-, mini-micro-, super-mini-, and micro-PCNL]) versus RIRS.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies and extracted data from the included studies. Our primary outcomes were stone-free rate, major complications, and need for secondary interventions. Our main secondary outcomes were unplanned medical visits to emergency/urgent care or outpatient clinic, length of hospital stay, ureteral stricture or injury, and quality of life. We performed statistical analyses using a random-effects model. We rated the certainty of evidence using GRADE criteria. We adopted a minimally contextualized approach with predefined thresholds for minimal clinically important differences (MCIDs).

MAIN RESULTS

We included 42 trials assessing the effects of PCNL versus RIRS in 4571 randomized participants. Twenty-two studies were published as full-text articles, and 20 were published as abstract proceedings. The average size of stones ranged from 10.1 mm to 39.1 mm. Most studies did not report sources of funding or conflicts of interest. The main results for the most important outcomes are summarized below. Stone-free rate PCNL compared with RIRS may improve stone-free rates (risk ratio [RR] 1.13, 95% confidence interval [CI] 1.08 to 1.18; I2 = 71%; 39 studies, 4088 participants; low-certainty evidence). Based on 770 participants per 1000 being stone-free with RIRS, this corresponds to 100 more (62 more to 139 more) stone-free participants per 1000 with PCNL (an absolute difference of 10%, where the predefined MCID was 5%). Major complications PCNL compared with RIRS probably has little or no effect on major complications (RR 0.86, 95% CI 0.59 to 1.25; I2 = 15%; 34 studies, 3649 participants; moderate-certainty evidence). Based on 31 complications in the RIRS group, this corresponds to six fewer (13 fewer to six more) major complications per 1000 with PCNL (an absolute difference of 0.6%, where the predefined MCID was 2%). Need for secondary interventions PCNL compared with RIRS may reduce the need for secondary interventions (RR 0.31, 95% CI 0.17 to 0.55; I2 = 61%; 21 studies, 2005 participants; low-certainty evidence). Based on 222 secondary interventions in the RIRS group, this corresponds to 153 fewer (185 fewer to 100 fewer) secondary interventions per 1000 with PCNL (an absolute difference of 15.3%, where the predefined MCID was 5%). Unplanned medical visits No studies reported unplanned medical visits. Length of hospital stay PCNL compared with RIRS may extend length of hospital stay (mean difference 1.04 days more, 95% CI 0.27 more to 1.81 more; I2 = 100%; 26 studies, 2804 participants; low-certainty evidence). This effect size is greater than the predefined MCID of one day. Ureteral stricture or injury PCNL compared with RIRS may have little or no effect on the occurrence of ureteral strictures (RR 0.93, 95% CI 0.39 to 2.21; I2 = 0%; 13 studies, 1574 participants; low-certainty evidence). Based on 14 ureteral strictures in the RIRS group, this corresponds to one fewer (nine fewer to 17 more) ureteral strictures per 1000 with PCNL (an absolute difference of 0.1%, where the predefined MCID was 2%). Quality of life No studies reported quality of life.

AUTHORS' CONCLUSIONS

Based on a large body of evidence from 42 trials, we found that PCNL compared with RIRS may improve stone-free rates and may reduce the need for secondary interventions, but probably has little or no effect on major complications. PCNL compared with RIRS may have little or no effect on ureteral stricture rates and may increase length of hospital stay. We found no evidence on unplanned medical visits or participant quality of life. Because of the considerable shortcomings of the included trials, the evidence for most outcomes was of low certainty. Access size for PCNL was less than 24 Fr in most studies that provided this information. We expect the findings of this review to be helpful for shared decision-making about management choices for individuals with renal stones.

Initial results of the implementation of an ambulatory mini percutaneous nephrolithotomy program

OBJECTIVE

To present our program for ambulatory mini percutaneous nephrolithotomy (mini-PCNL) and evaluate its initial results.

MATERIAL AND METHODS

We analyzed the implementation of the protocol into the clinical practice with the first 30 outpatient mini-PCNL cases performed in our center between April 2021 and September 2022. Demographic characteristics, perioperative variables, complications and need for unplanned health care, stone-free rate (SFR), stone type and patient satisfaction with the major ambulatory surgery (MAS) process were collected.

RESULTS

A total of 30 patients with a mean age of 60.2 ± 11.6 years who met the inclusion criteria underwent surgery. The mean stone size was 15 mm [range: 5-20]. No intraoperative complications were recorded. All patients except one were discharged the same day of surgery as planned. In the month following discharge, the rate of complications, emergency department (ED) revisits or hospital readmissions rates were 0%. Stone-free-rate (SFR) at 3 months was 83%. Overall satisfaction with the whole perioperative process was assessed with the EVAN-G questionnaire, obtaining 124.3 points out of a maximum of 150, which is equivalent to a 78.6% level of satisfaction.

CONCLUSION

Ambulatory mini-PCNL can be implemented as a treatment option in centers with experience in endourology, an established MAS Unit, and strictly selected patients. Our initial results show an adequate safety profile and high overall satisfaction perceived by patients undergoing the ambulatory approach.

Miniaturization in percutaneous nephrolithotomy: What is new?

Objective

To summarize recent advancements in mini-percutaneous nephrolithotomy (mini-PCNL) in surgical technique, stone removal strategy, lithotripsy, and surgical model from the current literature.

Methods

We conducted a narrative review of relevant English-language articles up to October 2022 using the PubMed and Web of Science databases. The following keywords were used in the search: "percutaneous nephrolithotomy", "minimally invasive percutaneous nephrolithotomy", "mini-PCNL", "mini-perc", "mPCNL", and "miniaturization".

Results

A series of new progress has been made in many aspects of mini-PCNL, such as further reduction of tract size-needle perc and further improvement of robotic-assisted PCNL-artificial intelligence-powered robotic devices.

Conclusion

Many studies and trials have been conducted to reduce morbidity and increase the safety and effectiveness of mini-PCNL. It is crucial to realize that miniaturization of PCNL requires not only a smaller percutaneous tract size, but also an adjustment strategically in renal access, stone removal, lithotripsy, and surgical model in general. More large-scale prospective research needs to be carried out to further validate and optimize the safety and effectiveness of mini-PCNL.

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.

Paediatric kidney stone surgery: state-of-the-art review

While urolithiasis in children is rare, the global incidence is rising, and the volume of minimally invasive surgeries being performed reflects this. There have been many developments in the technology, which have supported the advancement of these interventions. However, innovation of this kind has also resulted in wide-ranging practice patterns and debate regarding how they should be best implemented. This is in addition to the extra challenges faced when treating stone disease in children where the patient population often has a higher number of comorbidities and for example, the need to avoid risk such as ionising exposure is higher. The overall result is a number of challenges and controversies surrounding many facets of paediatric stone surgery such as imaging choice, follow-up and different treatment options, for example, medical expulsive therapy, shockwave lithotripsy, ureteroscopy, and percutaneous nephrolithotomy. This article provides an overview of the current status of paediatric stone surgery and discussion on the key topics of debate.

Mini-track, mini-nephroscopy, mini-ultrasonic probe percutaneous nephrolithotomy and its initial clinical application

Background

To assess the outcome of the mini-track, mini-nephroscopy, mini ultrasonic probe percutaneous nephrolithotomy for upper ureteral and kidney stones.

Methods

We collected data of 53 patients (55 kidney units) who underwent mini-track, mini-nephroscopy, mini-ultrasonic probe percutaneous nephrolithotomy between September 2020 and March 2021. The study included single and upper ureteral stones from 12 kidneys, multiple stones from 28 kidneys, and staghorn stones from 15 kidneys.

Results

The mean operative duration was 50.6 min, ranging from 15 to 200 min, whereas the mean lithotripsy and stone removal time was 17.2 min (3–45 min). Moreover, the mean postoperative length of stay was 4.0 days (1–7 days). Besides, the stone-free rate (SFR) of discharge was 89.1% (49/55). The mean hemoglobin drop was 15.3 mg/dL, ranging 1–32 mg/dL. Out of the total cases, only 4 of them displayed minor complications. The outcomes of < 40 mm versus ≥ 40 mm calculi were compared by performing subgroup analysis. The results demonstrated a longer operation duration (65.2 vs. 40.2 min), higher complication rate (13.0% vs. 3.3%), and lower SFR in the ≥ 40 mm calculi subgroup.

Conclusions

In summary, mini-track, mini-nephroscopy, mini-ultrasonic probe percutaneous nephrolithotomy is an effective and safe method to treat patients with upper ureteral and kidney calculi. This is especially significant for the stone size of 20–40 mm, demonstrating excellent SFR and a lower complication rate.

Mini Versus Standard Percutaneous Nephrolithotomy for the Management of Renal Stone Disease: Systematic Review and Meta-analysis of Randomized Controlled Trials

CONTEXT

Mini percutaneous nephrolithotomy (mPNL) involves the creation of a smaller access tract compared with standard PNL (sPNL). Smaller tract sizes could lead to decreased blood loss, pain, and need for blood transfusion. Previous studies on this topic have reported variable findings and were of poor quality.

OBJECTIVE

To compare the safety and efficacy of mPNL with those of sPNL for the management of patients with renal stone disease by conducting a systematic review and meta-analysis.

EVIDENCE ACQUISITION

Systematic literature search was performed to identify relevant randomized controlled trials (RCTs) for the review. The primary outcomes for the study were stone-free rate (SFR) and blood transfusion rate. The secondary outcomes were complication rates, fever, fall in hemoglobin, operative time, length of stay (LOS), need for auxiliary procedure, and visual analog scale (VAS) score at 24 h. We followed Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines, and the study protocol was registered with PROSPERO in priori (CRD42021252444).

EVIDENCE SYNTHESIS

In this review, 16 RCTs with 3961 patients were included. SFR was comparable between the two groups (risk ratio [RR] 1.01 [0.99, 1.04], p = 0.30), whereas the need for transfusion was lower with mPNL (RR 0.54 [0.37, 0.78], p = 0.001). Fall in hemoglobin (mean difference [MD] -0.67 [-0.93, -0.41], p = 0.000) and LOS (MD -0.59 [-0.81, -0.37], p = 0.000) were shorter with mPNL. Operative time was significantly shorter with sPNL (MD 8.28 [3.96, 12.59], p = 0.000). Complications were lower with mPNL (RR 0.89 [0.79, 0.97], p = 0.01). The need for auxiliary procedures (RR 0.77 [0.58, 1.03], p = 0.08) and VAS at 24 h (MD -0.79 [-1.63, 0.05], p = 0.06) were similar in the two groups.

CONCLUSIONS

Mini PNL has similar efficacy to sPNL in terms of SFRs. However, mPNL has a superior safety profile with fewer overall complications and a reduced need for blood transfusion.

PATIENT SUMMARY

In this study, we conducted a meta-analysis comparing mini and standard percutaneous nephrolithotomy (PNL) for the management of patients with renal stone disease. We showed that mini and standard PNL are associated with similar stone-free rates. Overall complications and the need for blood transfusion were lower with mini PNL.

Is percutaneous nephrolithotomy effective and safe for children with solitary kidney?

PURPOSE

To evaluate the safety and efficacy of percutaneous nephrolithotomy (PCNL) in pediatric patients with solitary kidneys and kidney stones.

METHODS

Thirty-nine patients (group A) with solitary kidney under 18 years of age who underwent PCNL between January 2015 and December 2021 were evaluated and analyzed. Forty-two patients (group B) with bilateral kidneys who underwent PCNL were determined as the control group and included in the analysis. Intraoperative and postoperative data such as demographic data, stone localization, bleeding and transfusion rates, operation time, complications, hospital stay, stone-free rates (SFR) and kidney function (glomerular filtration rate (eGFR)) were compared between the two groups. PCNL was performed with all patients in the prone position. Only a laser was used to fragment the stone in all cases. Stone-free was defined as the absence of residual stone fragments ≥ 2 mm in maximum diameter at 3 months on kidney, ureter and bladder (KUB) graphy, ultrasonography (US) or non-contrast tomography (NCCT).

RESULTS

The mean ages of the patients in Group A and B were 7.5 ± 2.6 and 8.5 ± 3.1 years, respectively. The mean stone size was 16.5 ± 4.1 and 17.0 ± 3.2 mm in group A and group B, respectively (p = 0.49). SFR rates in Groups A and B were 97.4% and 95.2% (p = 1.00). There was no statistically significant difference in terms of the operation time, perioperative blood transfusion, hemoglobin decrease and Clavien grade 1 complication rates (p > 0.05). However, double-J (JJ) stent placement, duration of nephrostomy and hospital stay were longer in the solitary kidney group (p < 0.05). There was a significant improvement in creatinine and eGFR levels in both groups at the postoperative sixth month (p < 0.05).

CONCLUSION

Our results show that PCNL is a safe and effective method in pediatric patients with solitary kidneys.

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

Objectives

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

Methods

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

Results

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

Conclusion

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

•

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

•

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

•

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

Paediatric stone management: innovations and standards

PURPOSE OF REVIEW

The aim of this study was to discuss current trends and recent developments in the surgical management of paediatric urolithiasis.

RECENT FINDINGS

Medical expulsive therapy (MET) is considered as an option for the treatment of children with ureter stones. Extracorporeal shockwave lithotripsy (SWL) remains as a first option for majority of kidney stones and upper ureter stones. Advances in endourology have led to increased adoption of retrograde intrarenal surgeries (RIRS) and percutaneous nephrolithotomy (PCNL/mini-PCNL/ultra-mini-PCNL/micro-PCNL).

SUMMARY

Management of paediatric stone disease has developed significantly in the past decade. However, the evidence in the literature remains disproportional to these advances. Well designed multicentric studies are still needed to compare effectiveness and safety of these procedures.

Primary hyperoxaluria type 1: urologic and therapeutic management

While the surgical approaches available in primary hyperoxaluria (PH) are common to all patients requiring intervention for urolithiasis, the indications for treatment and their corresponding toxicities are unique. Being a rare disease, we are guided by case series. This review summarizes the available literature highlighting the important disease-specific considerations. Shockwave lithotripsy (SWL) is of particular interest. It is generally the first-line treatment for stones in children, but here the stones produced will be relatively resistant to fragmentation. In addition, there are concerning reports in children of sudden unilateral decline in function in the treated kidney as measured by nuclear renography. Percutaneous nephrostolithotomy might intuitively seem favorable given the shortest drain duration and the ability to treat larger stones efficiently but, similar to SWL, rapid chronic kidney disease (CKD) progression has been seen postoperatively. Ureteroscopy is therefore generally the safest option, but considerations regarding stent encrustation, the growth of residual fragments and the large volume of stone often faced may limit this approach. The surgeon must balance the above with consideration of the patient's CKD status when considering a plan of monitoring and treating stones in PH.

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.

Endoscopic Combined Intrarenal Surgery Versus Percutaneous Nephrolithotomy for Complex Renal Stones: A Systematic Review and Meta-Analysis

Background: Endoscopic combined intrarenal surgery (ECIRS) adds ureteroscopic vision to percutaneous nephrolithotomy (PCNL), which can be helpful when dealing with complex renal stones. Yet, there is still no consensus on the superiority of ECIRS. We aimed to critically analyze the available evidence of studies comparing efficacy, safety, bleeding risk, and efficiency of ECIRS and PCNL. Methods: We searched for studies comparing efficacy (initial and final stone-free rate), safety (postoperative fever, overall and severe complications), efficiency (operative time and hospital stay) and bleeding risk between ECIRS and PCNL. Meta-analysis was performed. Results: Seven studies (919 patients) were identified. ECIRS provided a significantly higher initial stone-free rate, higher final stone-free rate, lower overall complications, lower severe complications, and lower rate of requiring blood transfusion. There was no difference between the two groups in terms of postoperative fever, hemoglobin drop, operative time, and hospital stay. In the subgroup analysis, both minimally invasive and conventional ECIRS were associated with a higher stone-free rate and lower complication outcomes. Conclusions: When treating complex renal stones, ECIRS has a better stone-free rate, fewer complications, and requires fewer blood transfusions compared with PCNL. Subgroups either with minimally invasive or conventional intervention showed a consistent trend.

Factors Affecting Residual Stone Rate, Operative Duration, and Complications in Patients Undergoing Minimally Invasive Percutaneous Nephrolithotomy

Background and objectives: Although minimally invasive percutaneous nephrolithotomy (MPCNL) has demonstrated its efficacy, complete stone clearance was not always achieved, necessitating a second procedure. The purpose of this study was to evaluate factors associated with residual stone rate, operative duration, complications, and hospital stay, in order to develop algorithms for pre-operative prognosis and planning. Materials and Methods: This retrospective study involved 163 Bulgarian patients who underwent MPCNL with Holmium: YAG lithotripsy for the treatment of kidney stones. Patients were considered stone-free if no visible fragments (<3 mm) were found on nephroscopy at the end of the procedure, as well as on postoperative X-ray and abdominal ultrasound on the first postoperative day. Results: Immediate postoperative stone-free outcome was attained for 83.43% of the patients (136/163). Residuals were associated with staghorn stones (OR = 72.48, 95% CI: 5.76 to 91.81); stones in two locations (OR = 21.91, 95% CI: 4.15 to 137.56); larger stone size (OR = 1.12, 95% CI: 1.006 to 1.25); and higher density (OR = 1.03, 95% CI:1.005 to 1.06). The overall categorization accuracy for these factors was 93.80%, AUC = 0.971 (95% CI: 0.932 to 0.991), 89.71% sensitivity, and 96.30% specificity. Predictors of prolonged operative duration were staghorn stones and volume, R-square (adj.) = 39.00%, p < 0.001. Longer hospitalization was predicted for patients with hydronephrosis and staghorn stones, R-square (adj.) = 6.82%, p = 0.003. Post-operative complications were rare, predominantly of Clavien-Dindo Grade 1, and were more frequent in patients with hydronephrosis. We did not find a link between their occurrence and the outcome of MPCNL. Conclusions: Staghorn stones and stones in more than one location showed the strongest association with residual stone rate. Staghorn stones and larger volume were linked with a longer operative duration. Hydronephrosis increased the risk of complications and longer hospitalization.

Comparison of Ultra-Mini Percutaneous Nephrolithotomy and Retrograde Intrarenal Surgery for Renal Stones: A Systematic Review and Meta-Analysis from the KSER Update Series

Miniaturized percutaneous nephrolithotomy (PCNL) and retrograde intrarenal surgery (RIRS) for renal stones have been developed to overcome the invasive disadvantages of PCNL. We aimed to compare the therapeutic effect and safety of ultra-mini percutaneous nephrolithotomy (UMPCNL) and RIRS for renal stones using an updated systematic review and meta-analysis. We searched clinical trials comparing UMPCNL and RIRS for renal stones using the PubMed, EMBASE, Cochrane Library, and Google Scholar databases up to October 2021. Seven studies were included in the current study. The renal stone size was 10–20 mm in three studies, 10–25 mm in one study, 10–35 mm in two studies, and not specified in one study. The stone-free rate of UMPCNL was higher than that of RIRS (p = 0.02; odds ratio (OR) = 2.01; 95% confidence interval (CI) = 1.12, 3.61). The complication rate showed no significant difference between UMPCNL and RIRS (p = 0.48; OR = 1.20; 95% CI = 0.73, 1.98). Regarding the operative time, UMPCNL was shorter than RIRS (p = 0.005; weighted mean difference (WMD) = −15.63; 95% CI = −26.60, −4.67). The hospital stay of UMPCNL was longer than that of RIRS (p = 0.0004; WMD = 1.48; 95% CI = 0.66, 2.31). UMPCNL showed higher efficacy than RIRS and similar safety to RIRS. UMPCNL may be a useful therapeutic option for moderate-sized 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.

Pediatric Stone Surgery: What Is Hot and What Is Not

PURPOSE OF REVIEW

We aim to highlight recent advances in technology and techniques for surgical management of urinary tract calculi in pediatric patients.

RECENT FINDINGS

Percutaneous nephrolithotomy (PCNL) is classically performed in the prone position. The supine PCNL was first attempted to overcome the shortcomings of difficult airway access, patient and surgeon discomfort. The supine PCNL, and subsequent modifications, has been successfully described in the pediatric population. Classically, PCNL has also been classically concluded with obligate placement of a nephrostomy tube and bladder catheter. Recently, tubeless and totally tubeless PCNL reduces pain and duration of hospitalization with satisfactory surgical outcomes in children. Finally, we describe the use of thulium laser technology, which offers improved efficacy in stone treatment and may supplant the current dominant technologies in coming years. Recent advances in pediatric stone surgery include supine PCNL, miniaturized PCNL instrumentation, tubeless procedures, and thulium laser technology.

A novel approach in creating nephrostomy using a double-lumen access sheath during endoscopic combined intrarenal surgery

Background

This study aimed to evaluate the safety and efficacy of an inner ureteral access sheath (i-UAS) with a double-lumen channel used in ureteroscopic lithotripsy (URS) as a dilator for the percutaneous tract in endoscopic combined intrarenal surgery (ECIRS).

Methods

This was a single-center cohort study conducted from January 2016 to April 2020. We used an i-UAS as a dilator and a double-lumen catheter to insert a safety guidewire during the creation of the nephrostomy tract in ECIRS. Univariate and multivariate analyses were performed to assess the association between the perioperative parameters and the use of i-UAS. The primary endpoint was perioperative complications, and secondary endpoints were stone-free rate (SFR), operative time, fluoroscopy time, and duration of hospitalization.

Results

In total, 221 patients were enrolled during the study period. Patients were divided into an i-UAS dilation group (n=108) and a one-shot dilation group (n=113). No differences were observed between the two groups in terms of patient history. Univariate analyses indicated that, in the i-UAS dilation group, the operative time was shorter [105.50 (83.75–143.25) vs. 121.00 (90.00–155.00) min; P=0.02] and the modified Valdivia position was more frequently selected. Multivariate analyses showed no significant differences in the frequency of complications, such as urinary injury or postoperative pyelonephritis, but it showed a significantly shorter operative time as well as fewer tract creation troubles in the i-UAS dilation group.

Conclusions

Using an i-UAS as a dilator and a double-lumen catheter to insert a safety guidewire during ECIRS is a convenient and safe technical method for creating a nephrostomy tract that can reduce the operative time.

Safety and efficacy of minimally invasive percutaneous nephrolithotomy for infantile nephrolithiasis. Single centre experience from Pakistan

OBJECTIVE

To assess the efficacy and safety of mini-percutaneous nephrolithotomy (PCNL) for small renal stones 1-2 cm in size in infants less than one year.

MATERIAL AND METHODS

This descriptive case series was conducted in the department of pediatric urology Institute of Kidney Diseases Peshawar, Pakistan, from March 2019 to March 2022. All the patients underwent mini-PCNL in prone position under GA with 14 Fr access sheath and 10 Fr nephroscope. Stone clearance was assessed by non-contrast CT KUB at 30th postoperative day. Patients with no residual fragments on the non-contrast CT KUB were defined as stone-free. Patients with residual fragments of any size were defined as procedure failure. Safety was determined in terms of intra and postoperative complications.

RESULTS

A total of 51 infants were included in the study. The mean age of patients was 9.6 + 1.8 (5-12 month). The mean stone size was 15.8 + 2.7 (10-21) mm in length and 12.3 + 2.2 (8-17) mm in width. PCNL mean operative time was 51.6 ± 7.1 (40-70) minutes. Complete stone clearance at one month was observed in 46 (90.2%) patients. Residual fragments were seen in 5(9.8%) patients with a mean size of 1.6 + 0.4 (0.9-2.0) mm. None of the patients required any additional procedure for clearance of stones. In 7 (13.7%) patients, some post-operative complications were observe, all were grade I complications, including fever in 5(9.8%) and transient hematuria in 2(3.9%) patients.

CONCLUSION

Mini-PCNL is a safe and effective treatment for renal stones in infants measuring 1-2 cm with high SFR and an acceptable complication rate.

Pediatric Urolithiasis: Current Surgical Strategies and Future Perspectives

New technological innovations and cutting-edge techniques have led to important changes in the surgical management of pediatric urolithiasis. Miniaturized technologies and minimally invasive approaches have been increasingly used in children with urinary stones to minimize surgical complications and improve patient outcomes. Moreover, the new computer technologies of the digital era have been opening new horizons for the preoperative planning and surgical treatment of children with urinary calculi. Three-dimensional modeling reconstructions, virtual, augmented, and mixed reality are rapidly approaching the surgical practice, equipping surgeons with powerful instruments to enhance the real-time intraoperative visualization of normal and pathological structures. The broad range of possibilities offered by these technological innovations in the adult population finds increasing applications in pediatrics, offering a more detailed visualization of small anatomical structures. This review illustrates the most promising techniques and devices to enhance the surgical treatment of pediatric urolithiasis in children, aiming to favor an early adoption and to stimulate more research on this topic.

Mini Percutaneous Kidney Stone Removal: Applicable Technologies

Percutaneous nephrolithotomy (PCNL) remains the treatment of choice for large and complex renal stones. The technological advances over the past several decades gave birth to different varieties of minimally invasive PCNLs, including the mini-PCNL, ultra-mini PCNL, super mini-PCNL, and micro-PCNL, with indications being extended to stones even larger than 20 mm. This article provides an update of all these available techniques of miniaturized PCNL along with its anatomic and physiologic impact. This should assist urologists in providing a personalized approach to the patient based on various patient- and stone-related factors to provide the best of all available technology for treatment.

A single centre experience of percutaneous nephrolithotomy in infants and its long-term outcomes

BACKGROUND

Renal stones in infants requiring Percutaneous nephrolithotomy (PCNL) is rare. There is insufficient literature on the long-term implications of PCNL in growing kidneys of these children.

OBJECTIVES

To review our experience of PCNL amongst infants i.e., < 1year of age and to analyse the safety and efficacy of this procedure and assess its long-term renal outcomes.

STUDY DESIGN

This was a retrospective analysis of a prospectively maintained data base between 2005 and 2020. All infants with unilateral renal stones >12 mm underwent PCNL. Changes in the serum creatinine, estimated glomerular filtration rate and renal size prior to the PCNL and at the last follow up were monitored. The demographics, clinical profile, operative details, post-operative complications and follow up data were collated and analyzed.

RESULTS

86 children were diagnosed with renal stones of whom, 24 infants met our inclusion criteria and were included in the review. The average age was 9.75 months with fever being the commonest presenting symptom. Five infants were diagnosed with metabolic abnormalities, hypercalciuria being the commonest. Majority of the infants (22) had single stones and the lower calyx was the commonest site (50%). The mean stone burden was 19.5 mm. The stone free rate was 91% during the primary PCNL, which increased to 100% after re-do PCNL. The overall complication rate was 16% which was graded by the modified Clavien Dindo scale for surgical complications. The median follow up period was 144 months and average age at the last follow up was 10.5 years. At the last follow up, a mean serum creatinine of 0.4 mg/dl, mean estimated glomerular filtration rate of 98 ml/min/1.72 m² and a mean renal size of 8.3 cm was recorded, which was comparable to that of a normal child, thus signifying no deterioration of renal functions and renal growth. Three children showed the presence of cortical scars on an isotope scan at follow up. However, all the 24 operated renal units demonstrated preserved renal functions.

DISCUSSION & CONCLUSION

PCNL performed during infancy does not hinder the growth potential of the kidney. Each of the 24 children achieved the target renal size and estimated glomerular filtration rate corresponding to the duration and body size at the end of the follow-up. Thus, PCNL in infants <1 year of age is safe and effective with no adverse effects at long term follow-up.

Pooled-analysis of efficacy and safety of minimally invasive versus standard percutaneous nephrolithotomy

BACKGROUND

This study aimed to assess the efficacy and safety of minimally invasive percutaneous nephrolithotomy (MPCNL) versus standard percutaneous nephrolithotomy in patients with renal and upper ureteric stones.

METHODS

We conducted a pooled analysis on randomized controlled trials (RCTs). The eligible RCTs were selected from the following databases: MEDLINE, Embase, Web of Science, and the Cochrane Library. The reference lists of retrieved studies were also investigated.

RESULTS

Our analysis included 10 RCTs with 1612 patients. Pooled data from 10 RCTs revealed the following: stone-free rate (odds ratio = 1.46, 95% confidence interval (CI) [1.12,1.88], P = .004), operative time (mean difference [MD]  = 4.10, 95% CI [-1.37,9.56], P = .14), length of hospital stay (MD = -15.31, 95% CI [-29.43,-1.19], P = .03), hemoglobin decrease (MD = -0.86, 95% CI [-1.19,-0.53], P < .00001), postoperative fever (MD = 0.83, 95% CI [0.49,1.40], P = .49), and urine leakage (MD = 0.59, 95% CI [0.25,1.37], P = .22). Besides, we performed sub-group analysis based on vacuum suction effect and multiple kidney stones. For vacuum suction effect, it revealed the following: stone-free rate in vacuum suction group (P = .007) and in non-vacuum suction group (P = .19). Operative time in vacuum suction group (P = .89), non-vacuum suction group (P = .16). Postoperative fever in vacuum suction group (P = .49), non-vacuum suction group (P = .85).

CONCLUSION

This pooled analysis indicated that MPCNL was a safe and effective method for treating renal stones compared with standard percutaneous nephrolithotomy. Besides, the vacuum suction effect in MPCNL played a more important role. When it comes to multiple or staghorn stones, the longer operative time in MPCNL could not be ignored.

Safety and efficacy of ultrasound-guided low-pressure perfusion mini-percutaneous nephrolithotomy in children aged 1-7 years: a retrospective observational study

PURPOSE

This article analyzed the safety and efficacy of ultrasound-guided mini-percutaneous nephrolithotomy (MPCNL) with low-pressure perfusion for the treatment of upper urinary tract stones in children.

METHODS

The clinical data of 690 patients (805 renal units) aged 1-7 years were retrospectively analyzed in terms of postoperative outcome.

RESULTS

The mean patient age was 3.7 ± 1.6 years, and the stone burden was 2.8 ± 2.1 cm². A middle posterior calyceal puncture was created in 719 (89%) renal units, and 16F puncture tracts were the most common method used in 557 (69%) renal units. The stone-free rate was 711 (88%) renal units, and the mean operation time was 35 ± 15.3 min (between 15 and 110 min). Among all cases, the transfusion rate was 4 (0.6%) patients, and the mean decrease in hemoglobin was 1.3 ± 0.9 g/L. In addition, the incidence rates of fever, sepsis, perirenal effusion, and intraperitoneal effusion were 40 (5.9%), 3 (0.4%), 28 (4.1%), and 8 (1.2%) patients, respectively. After the operation, 348 patients were followed-up for 32.8 ± 11.3 months, and stone recurrence occurred in 136 (39%) of 348 patients.

CONCLUSIONS

This study suggests that ultrasound-guided MPCNL with low-pressure perfusion technology is a safe and feasible treatment.

A systematic review and meta-analysis of minimally invasive vs. standard percutaneous nephrolithotomy in the surgical management of renal stones

The present study aimed to assess current evidence on the effectiveness and safety of minimally invasive vs. standard percutaneous nephrolithotomy (PCNL) in the management of renal stones. A systematic search of electronic databases, which included PubMed, EMBASE and the Cochrane Library up to May 2019 was performed. Using Review Manager statistical software (version 5.3), primary outcomes, including stone-free rates (SFRs), were evaluated. Meanwhile, analysis was also performed to compare secondary outcomes, such as peri- and postoperative complications and operative data. Fourteen studies involving 1,611 patients with renal stones were analyzed based on the inclusion criteria. On the basis of the present analysis, mini percutaneous nephrolithotomy (MPCNL) was proven to have non-inferior clinical efficacy with respect to the SFR compared with PCNL [odds ratio (OR)=1.10; 95% confidence interval (CI), 0.84-1.44; P=0.48]. In addition, the meta-analysis showed that MPCNL had a significantly lower hemoglobin decrease [mean difference (MD)=-0.68; 95% CI, -1.05 to -0.31; P=0.0003] and fewer blood transfusions (OR=0.36; 95% CI, 0.18-0.71; P=0.003) compared with PCNL. Moreover, the MPCNL group had a shorter inpatient stay (MD=-0.81; 95% CI, -1.55 to -0.08; P=0.03) compared with the PCNL group. However, the overall evidence was insufficient to suggest a statistically significant difference in the adverse event profile for MPCNL compared with PCNL. The present meta-analysis indicates that MPCNL is an effective method for treating renal stones. Compared with PCNL, MPCNL not only has similarly high SFRs but is also associated with less blood loss, fewer blood transfusions, more favorable recovery time and shorter inpatient stays. However, the findings of the present study should be further confirmed by well-designed prospective randomized controlled trials with a larger patient series.

Safety and efficacy of mini-percutaneous nephrolithotomy as daycare procedure: a prospective observational study

Background

To evaluate the safety, feasibility of mini-percutaneous nephrolithotomy (mPCNL) being carried out as a daycare surgery and to study the re-admission, stone clearance rate and complication rates following mPCNL. We also sought to find out the rate of requirement of ancillary procedure, after mPCNL.

Methods

In this prospective observational study, easily accessible patients above 18 years of age with renal and/or upper ureteric calculi, who underwent mPCNL between September 2018 and February 2020, were included. Seventy patients were selected, as per statistical methods. Preoperative evaluation including history, blood and urine investigations and radiological images was collected. Intra-operative and post-operative events were analyzed. Written consent was obtained from the patients to participate in the study and to publish their data. Institutional Ethical and scientific committee clearance was obtained.

Results

Out of 70 patients who underwent mPCNL in the study, in the age group ranging from 24–68 years, most of the cases were partial staghorn with maximum size of stone up to about 3.5 cm. Inferior calyx was most frequently punctured. Six cases had multipuncture mPCNL, four patients had bilateral procedure, and two had supra-costal puncture. Eighteen patients had tubeless mPCNL, of which four were totally tubeless procedures. Four patients had hematuria, none requiring transfusion. Two patients had sepsis, managed with higher antibiotics. Limitation of the study was the sample size. To derive a sturdy conclusion, large scale studies are recommended.

Conclusions

We can conclude that mPCNL can be safely done as daycare or ambulatory surgery in properly selected patients. In centers with experienced urologists, bilateral and multipuncture mPCNL can be done as an ambulatory surgery. Thus, this addresses the stone disease as well as cost containment, without patient safety being compromised. Bed occupancy rate is reduced, helping effective utilization of hospital resources.

A comparative study of epidural anesthesia with dexmedetomidine infusion versus general anesthesia for percutaneous nephrolithotomy

Background:

There has been considerable debate regarding the ideal anaesthetic technique for Percutaneous Nephrolithotomy (PCNL). PCNL is usually performed under general anaesthesia (GA) in prone position. The prone position under GA is associated with various complications. To address these complications, our study was carried out to determine whether epidural anaesthesia [EA] with dexmedetomidine sedation can be a better alternative to GA for PCNL.

Aims and Objectives:

To compare the efficacy and feasibility of performing PCNL under EA in combination with dexmedetomidine infusion.

Methods and Material:

Out of 225 patients observed in this study, 115 patients (group A) underwent PCNL under EA with dexmedetomidine infusion and 110 patients (group B) underwent PCNL under GA.

Results:

Mean time to the first dose of rescue analgesia was significantly increased in Epidural group (328.17 ± 63.74) compared to GA group (72.09 min, p < .0001) and the mean Visual analog scale [VAS] scores were significantly lower in epidural compared to GA group at different time intervals during the first 24 h after surgery (p<0.05). Patients in epidural group had significantly less post-operative nausea, vomiting (6.1 % vs 13.6 %), and significantly less shivering (12.2% vs 33.6%). Mean patient satisfaction score in epidural group was significantly higher (8.75 ± 1.29 vs 8.14 ± 1.39, p=0.001); however, the mean surgeon satisfaction score was comparable among the two groups (8.76 ± 1.39 in Group A and 8.61 ± 1.35 in Group B, p=0.421).

Conclusions:

Our study shows that EA is an equally effective alternative to GA for PCNL, with more patient satisfaction, less postoperative pain, early ambulation and postoperative recovery, less systemic analgesic requirements and less adverse effects.

Minimally Invasive Percutaneous Nephrolithotomy: Initial North American Experience

Introduction and Objectives: The goal of this study is to evaluate the outcomes in a cohort of patients who underwent minimally invasive percutaneous nephrolithotomy (MIP) at a single institution from 2017 to 2019. Methods: Sixty patients at a single institution with two different surgeons underwent MIP from 2017 to 2019. The MIP technique uses a proprietary nephroscope with a "vacuum" technique for stone evacuation. Patients were identified who had postoperative CT scan imaging available for direct review. A prospectively maintained database was queried along with retrospective chart review to evaluate the stone-free rate defined as no stones on CT imaging. Preoperative, intraoperative, and postoperative variables were analyzed including initial stone size, access type (fluoroscopic vs ultrasonic), access location, operative positioning (supine vs prone), operative time, and 60-day complications. Results: Forty-six of 60 patients had CT imaging postoperatively that were reviewable. Of these, 43% (n = 20) were stone free as defined by no identifiable fragments seen, 11% (n = 5) had residual fragments 0 to 2 mm, 7% (n = 3) had residual fragments 2 to 4 mm, and 39% (n = 18) had residual fragments >4 mm. Mean initial stone size was 21 mm (1.9-84 mm). Sixty percent (n = 28) of the patients were discharged the same day as surgery. Fifty-one percent (n = 24) of access was achieved through ultrasound alone. Seventeen percent of patients (n = 8) had a complication within 30 days of surgery. All complications were Clavien III or lower with unplanned return to operating room rate of 2% (n = 1). Conclusions: We present North America's first single institution analysis of MIP cases with acceptable outcomes comparable with both retrograde intrarenal surgery and standard percutaneous nephrolithotomy. The exact role of MIP in renal stone disease needs to be determined by future studies that critically assess their outcomes.

Endourologic and Retroperitoneoscopic Combined Mininvasive Management of Cystine Urolithiasis in an Infant of 13 Months of Life

Background: There are limited data about urolithiasis in young infants, especially in class age younger than 2 years. Case presentation: We report the case of a child <2 years old (13 months) affected by metabolic urolithiasis (cystinuria), and renal hypertension. He was admitted to our ward from the pediatric emergency room for fever, lack of appetite, irritability, and abdominal pain crisis. Ultrasonography (US) described a huge stone (15 mm) in dilated left renal pelvis (20 mm) associated with distal ureteral ectasia (7 mm). Urine and blood diagnostic assessments were performed. Hydropenic therapy and urine alkalization were started without success. The child underwent an ureteroscopy (URS) with a 4.5-6.5F rigid ureteroscope aiming to reach the renal pelvis and perform holmium: yttrium-aluminum-garnet laser stone disintegration. During the procedure, the ureter presented two unexpected stones in the distal portion (missed on US). A laser ureteral lithotripsy was effectively performed extracting smaller stone fragments. Ureteral kinking, confirmed by ascending pyelography, made it impossible to reach renal pelvis with the ureteroscope. The child was further studied with a CT scan that revealed a massive stone involvement of the left excretory pathway. Metabolic and urine assessment revealed a metabolic disease: cystinuria. To remove renal stones, an operative retroperitoneoscopy (RP) was performed. During the procedure was identified a lesion of the pelvis (secondary to stone decubitus) with urine tearing and massive perirenal inflammation. The stone was removed and pelvis was sutured. Postoperatively, the patient was stone free without major complications. Conclusions: In particular cases (younger patients, ureteral kinking, and renal failure risk), a totally combinated minimally invasive access (URS, laser stone fragmentation, and RP) can be a valid alternative to micro percutaneous nephrolithotomy or to massive open treatment. In fact, rigid URS represents a valid minimally invasive approach either for examination or for laser treatment of pediatric urinary tract stones. With important ureteral kinking, RP must be considered by experienced pediatric urologists.

A comparison among PCNL, Miniperc and Ultraminiperc for lower calyceal stones between 1 and 2 cm: a prospective, comparative, multicenter and randomised study

Background

Conventional Percutaneous Lithotripsy (PCNL) has been an effective, successful and easy approach for especially > 1 cm sized calyceal stones however risks of complications and nephron loss are inevitable. Our aim is to compare the efficacy and safety of PCNL, MiniPerc (MP) and UltraMiniPerc (UMP) for lower calyceal stones between 1 and 2 cm with a multicenter prospective randomized study.

Methods

Between January 2015 and June 2018, 132 consecutive patients with single lower calyceal stone were enrolled. Patients were randomized in three groups; A: PCNL; B: MP; C: UMP. 44 patients for the Group A, 47 for Group B and 41 for Group C. Exclusion criterias were the presence of coagulation impairments, age of < 18 or > 75, presence of infection or serious comorbidities. Patients were controlled with computerized tomography scan after 3 months. A negative CT or an asymptomatic patient with stone fragments < 3 mm size were the criteria to assess the stone-free status. Patient characteristics, stone free rates (SFR) s, complications and re-treatment rates were analyzed.

Results

The mean stone size were 16.38, 16.82 and 15.23 mm respectively in Group A, B and C(p = 0.34). The overall SFR was significantly higher in Group A (86.3%) and B (82.9%) as compared to Group C (78%)(p < 0.05). The re-treatment rate was significantly higher in Group C (12.1%) and complication rates was higher in Group A (13.6%) as compared to others(p < 0.05). The hospitalization was significantly shorter in Group C compared to Group A (p = 0.04).

Conclusions

PCNL and MP showed higher efficacy than UMP to obtain a better SFR. Auxiliary and re-treatment rates were higher in UMP. On the other hand for such this kind of stones PCNL had more complications. Overall evaluation favors MP as a better indication in stones 1–2 cm size.

Minimally invasive percutaneous nephrolithotomy (PCNL): Techniques and outcomes

Minimally invasive percutaneous nephrolithotomy (PCNL) was introduced to decrease the morbidity of the standard PCNL (sPCNL). Thereafter, many modifications and techniques have been presented with the introduction of different miniaturized PCNL (mPCNL) techniques, such as micro-PCNL and ultra-mini-PCNL (UMP). As of present, none of the techniques has displaced the sPCNL. Nonetheless, mini-PCNL has continuously widening indications and has been proposed to have significant advantages over sPCNL. In the current review, each technique is presented while discussing the advantages and disadvantages of each approach. A comprehensive review of the current literature has been performed. Articles related to the topic were retrieved and critically analyzed. Less peri-operative bleeding and shorter hospital stay were the most important advantages advocated for mini-PCNL. Although the performance of mini-PCNL is safe, the utilization of micro-PCNL and UMP should be done with caution.

Management of staghorn stones in special situations

Staghorn stones have always been a challenge for urologists, especially in some special situations, such as horseshoe kidney, ectopic kidney, paediatric kidney, and solitary kidney. The treatment of these staghorn stones must be aggressive because they can lead to renal function loss and serious complications. The gold-standard management for staghorn stones is surgical treatment with the aim of clearing the stones and preserving renal function. Treatment methods for staghorn stones have developed rapidly, such as extracorporeal shock wave lithotripsy, retrograde intrarenal surgery, percutaneous nephrolithotomy and laparoscopy and open surgery. Whether the standard procedures for staghorn stones can also apply to these stones in special situations is still not agreed upon. The decision should be made individually according to the circumstances of the patient. In this review, we evaluates the previous studies and comments on the management of staghorn stones under special situations in the hope of guiding the optimal choice for urologists.

Multitract percutaneous nephrolithotomy in staghorn calculus

Staghorn calculi are branched stones which occupy a majority portion of the pelvicaliceal system. An untreated staghorn calculus over time can damage the kidney and deteriorate its function and/or cause life threatening sepsis. Total stone clearance is an important goal in order to eradicate any infective focus, relieve obstruction, prevent recurrence and preserve the kidney function. Percutaneous nephrolithotomy (PCNL) is currently the accepted first-line treatment option for staghorn calculi. The options available are single-tract PCNL with an auxiliary procedure like shockwave lithotripsy, single-tract PCNL with flexible nephroscopy, or multitract PCNL. Each has its own pros and cons. But the ultimate goal of treatment for any patient with staghorn calculi should be safety, cost-effectiveness, and to achieve total stone clearance. With this article, we review the management of staghorn calculi with multiple percutaneous (“multitract”) access, its advantages and disadvantages and its current position by studying the various published materials across the globe.

Minimally invasive versus standard endoscopic combined intrarenal surgery for renal stones: a retrospective pilot study analysis

PURPOSE

The effect of combining miniaturization with endoscopic combined intrarenal surgery (ECIRS) is unclear. Thus, we compared the treatment outcomes between minimally invasive ECIRS (mini-ECIRS) using 16.5 Fr percutaneous access sheath and standard ECIRS using 24 Fr access sheath for renal stones MATERIALS AND METHODS: We retrospectively analyzed consecutive patients who underwent single session mini or standard-ECIRS in the modified Valdivia position for renal stones between April 2009 and May 2016. To adjust for patient characteristics, 77 pairs were matched using preoperative parameters including age, sex, history of febrile urinary tract infection (UTI), stone surface area, number of involved calyces, and staghorn calculi.

RESULTS

The stone free rate (SFR) was similar between mini and standard ECIRS according to non-contrast computed tomography (61.1% vs. 52.0%, p = 0.388). The rate of perioperative complications exceeding grade 2 based on the Clavien-Dindo classification was similar in both groups (19.5% vs. 26.0%, p = 0.442). Severe complications exceeding grade 3 were also similar in both groups (2.6% vs. 3.9%, p > 0.99). Two cases of septic shock were noted in each group. Although there was no difference regarding bleeding-related complications (2.6% vs. 6.5%, p = 0.442), pseudoaneurysm or blood transfusion was not observed in the mini-ECIRS group. Pain visual analog scale values in the perioperative period were lower in the mini-ECIRS group (1.34 ± 1.08 vs. 1.69 ± 1.23, p = 0.062).

CONCLUSIONS

This study demonstrated that, compared to standard ECIRS, mini-ECIRS maintained SFR without increasing perioperative complications, tended to reduce postoperative pain and had a potential to reduce bleeding-related complications. This report suggests the advantages of ECIRS miniaturization for renal stones.

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

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

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 in Children: Analysis of Nationwide Hospitalizations and Short-Term Outcomes for the United States, 2001-2014

OBJECTIVE

To describe population-wide utilization rates and outcomes of percutaneous nephrolithotomy (PCNL) in the management of pediatric upper urinary tract calculi (UUTC).

PATIENTS AND METHODS

Patients <18 years with a diagnosis of UUTC, who underwent PCNL between 2001 and 2014 were identified from the National Inpatient Sample database. Annual PCNL rates, based on the at-risk population for each year, were estimated, and change in utilization rate was analyzed using negative binomial regression. Perioperative outcomes, hospital length of stay (LOS), and costs were determined; continuous and categorical variables were analyzed using nonparametric tests and Chi-squared tests, respectively. Trends tests and multivariable analyses (MVAs) were also performed where appropriate.

RESULTS

An estimated 3206 pediatric PCNL procedures were performed. Mean annual PCNL rate increased significantly relative to 2001 (incidence rate ratio = 1.40; 95% confidence interval 1.15-1.71, p = 0.001). Proportion of PCNL as a fraction of all inpatient surgical procedures for UUTC also significantly increased over time, from 15.7% in 2001 to 26.4% in 2014 (p < 0.0001). Complications overall occurred in 20.7% of cases, with a significantly rising rate over time period (p < 0.0001). Complication rates were similar across hospital types and geographic regions. Median hospitalization cost was significantly higher for the West than for each of the other regions (p < 0.05 in each case). Median LOS was also highest for the West (4 days vs 3 days for each of the other regions). In MVA, significant predictors of both increased LOS and costs included black race, comorbidities of hypertension, diabetes, coagulopathy and neurologic disease, hospitalization in the South, and presence of complications. Race, gender, comorbidities, and treatment year were among the predictors of complications.

CONCLUSIONS

PCNL utilization in the management of pediatric UUTC has significantly increased since 2001, with an associated increase in complication rates, although major complications were uncommon. Regional variations in costs and LOS were evident.