Endourological management of pediatric stone disease: present status

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.

Randomized controlled trial of NSAID prior to cystoscopic ureteral stent removal in a pediatric population

INTRODUCTION

Ureteral spasm, common with ureteral stents, is partially mediated by prostaglandins and may be suppressed by cyclooxygenase inhibitors like non-steroidal anti-inflammatory (NSAIDs). Practices currently vary widely for pain management in patients with ureteral stents, sometimes including opioids.

OBJECTIVE

We aimed to determine if NSAID given prior to stent removal would reduce postoperative pain. We hypothesized there would be at least a 75% reduction in postoperative severe pain (pain score ≥7) in patients receiving ibuprofen compared to placebo.

STUDY DESIGN

We performed a double-blind, placebo-controlled randomized controlled trial on pediatric urology patients with an indwelling ureteral stent undergoing removal in the operating room from 2014 to 2019. 20 patients in each arm were needed to achieve 80% power to detect a 75% reduction in the estimated 55% incidence of severe postoperative pain (α = 0.05). Patients ≥4 years old who had a unilateral stent placed after treatment of urolithiasis or ureteropelvic junction obstruction were randomized to NSAID or placebo in a 1:1 ratio at least 15 min prior to scheduled stent removal. Patients estimated pain using Faces Pain Scale-Revised (FPS-R) or visual analogue scale (VAS) prior to and 24 h after stent removal.

RESULTS

254 patients undergoing stent removal were assessed for eligibility, and 44 randomized patients were analyzed using intention to treat analysis. The cohorts were demographically similar and received similar anesthesia treatment. There was no significant difference in maximum post anesthesia care unit pain score (p = 0.269) or use of in-hospital opioids (p = 0.626) between the two groups. No difference was seen in the incidence of severe postoperative pain (p = 1.0), thus rejecting the hypothesis. Significant worsened postoperative pain (pain score increases of ≥2 between time points) decreased from 22.7% to 13.6% between placebo and NSAID, but this did not reach significance (p = 0.410).

DISCUSSION

There was no difference in postoperative pain for patients undergoing ureteral stent removal given preoperative NSAID versus placebo. The incidence of severe pain before and after stent removal was low, ranging from 4.5 to 9.1%.

CONCLUSION

Research to understand the etiology of pain after stent removal and techniques to minimize or prevent discomfort should continue in order to optimize patient outcomes.

Small Ureteral Access Sheath in Treating Paediatric Urolithiasis: A Single Centre Experience

Introduction

Urolithiasis is not commonly encountered in the pediatric population. The adoption of ureteral access sheaths (UAS) facilitates the passage to the pediatric ureter and limits the harm and ureteral injury. However, the debate continues regarding whether or not to use UAS in children.

Objective

To assess the safety and outcomes of using UAS in the treatment of pediatric renal and ureteral stones.

Study Design

This was a prospective cohort study of 14 pediatric patients who underwent flexible ureteroscopy (fURS) with the use of UAS for symptomatic renal and ureteric stones.

Results

Of the fourteen enrolled patients, nine (64.3%) were males, and five (35.7%) were females with an average age of 9.5 years. Eleven (78.6%) of the patients were rendered stone-free. The average operative time was 55.7 min. None of the patients developed any complications. The stone-free rate was significantly higher with stone burdens of ≤10 mm (p ≤ 0.05).

Conclusion

The use of UAS in children facilitates the passage of a flexible ureteroscope without complications. The procedure is considered to be efficient and safe with minimal morbidity.

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

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

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

Objective

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

Patients and methods

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

Results

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

Conclusion

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

Abbreviations

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

Minimally Invasive Approaches in Pediatric Urolithiasis. The Experience of Two Italian Centers of Pediatric Surgery

Background: Over the last 30 years, the incidence of pediatric urolithiasis (PU) has been increasing and the surgical management has evolved toward a minimally invasive approach (MIA). We reported the experience of two Centers of Pediatric Surgery in the management of PU, focusing on MIA as first choice in treatment. Methods: Data were retrospectively analyzed from October 2009 to October 2019 in children with urolithiasis who were admitted to two referral Italian Centers of Pediatric Surgery. Demographic and clinical data of the patients, features of the urolithiasis, type of surgery were considered. Results: Seventy patients (7.3 ± 5.0 years) with normal renal function were treated for calculi in the pyelocaliceal system (45.7%), ureter (34.3%), bladder (4.3%), urethra (1.4%), and multiple locations (14.3%). Size of calculi was >10 mm in 55.7% of cases (kidney>bladder/urethra>multiple>ureter, p = 0.01). Symptoms were present in 75.7% of patients. Family history was positive in 16.9% of cases. MIA was performed in 59 patients (84.3%): 11.8% shockwave lithotripsy (kidney>ureter>multiple); 32.2% ureteral retrograde surgery (ureteral>other localizations); 30.5% retrograde intrarenal surgery (kidney>other localizations); and 25.4% other procedures including percutaneous nephrolithotomy, cystoscopic bladder stone removal or laser cystolithotripsy (kidney>bladder>multiple). Preoperative stenting was necessary in 52.8% of cases. Four MIA procedures (6.9%, kidney>ureter/multiple) were converted to open surgery. Open surgery was required as first approach in 15.7% of patients (kidney>ureter>multiple) who needed urgent surgery or had associated congenital renal anomalies. In 18/70 of children (25.7%), with prevalence of stones in kidney and multiple location (p < 0.01), a second procedure completed the treatment (88.8% MIA). Intraoperative difficulties were recorded in 8.5% of cases, without difference between location and size of calculi. Late complications (5.7%) were related to displacement and infection of the ureteral stent. Conclusions: MIA resulted to be feasible in more than 75% of primary surgery and in more than 85% of cases requiring a second procedure. Preoperative stent was mandatory in more than 50% of children. The technological evolution allowed to overcome many of the technical difficulties related to the approach to the papilla and lower calyxes. Open surgery is reserved for selected cases and endoscopic surgery represents the best choice of treatment for PU.

The Efficacy of Ultra-thin Semi-rigid Ureteroscopy with Holmium Laser Lithotripsy in Pediatric Ureteral Stones: A Single-center Experience

Introduction

The aim of this study was to present our results regarding the feasibility and possible complications of 4.5 Fr semi-rigid ureterorenoscopy (URS) treatments in pediatric patients.

Methods

The files and computer records of a total of 33 pediatric patients (20 males and 13 females), who underwent URS procedures for ureteral stones > 5 mm between January 2013 and June 2017, were retrospectively reviewed. A 4.5 Fr semi-rigid ureteroscope (Ultrathin 4.5/6.5 Fr Ureterorenoscope; Richard Wolf GmbH, Knittlingen, Germany) was used for the URS procedures. For the stone-free rate evaluations, abdominopelvic ultrasound or direct radiography scans were performed one week after the surgery, and low-dose non-contrast computed tomography (CT) was performed during the first month.

Results

The mean age of the patients was 9.8 ± 2.8 (range 4-16) years old, and the mean ureteral stone size was 8.9 ± 1.4 (range 6-13) mm. The mean surgical duration was 45 ± 21.2 (range 30-75) minutes, and the mean hospital stay length was 1.2 (range 1-4) days. Minor complications occurred in five (15.1%) of the patients. The success rates for the first week and first month were 90.9% and 96.9%, respectively.

Conclusion

The endoscopic management of pediatric ureteral stones using a 4.5 Fr ureteroscope seems to be a safe and feasible treatment option with high success and low complication rates.

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.

Flexible ureterorenoscopy to treat upper urinary tract stones in children

Development of surgical expertise and technology has affected the way renal tract stones are treated. Our hypothesis was that flexible ureteroscopy (FURS) for upper tract stones in children produces good results. Our outcomes were reviewed. A retrospective case note review was performed for children with upper tract calculi who were treated by FURS. There were 56 stone episodes in 36 patients. Median age was 10.6 years. Stones were 3-23 mm (median 8 mm); 64.3% had multiple calculi. Median follow-up was for 17.1 months. After the first FURS there was stone clearance in 42/56 (75%). Although there were no immediate complications, two required re-admission; one with stent symptoms, the other with urinary infection. A second FURS was performed in 11, bringing the cumulative clearance to 89%, although this was often done as "another look" before stent removal. There was no statistically significant difference in stone clearance after first FURS for those with single stones (81.0%) compared to those with multiple stones (72.2%). Clearance rates of more than 70% after first FURS were achieved with stones of up to 17 mm. Unexpected disease was found and treated during FURS in 9 (16.1%) children. FURS is safe in children and good clearance rates are achieved. Multiple stones at different sites may be treated during the same treatment. In addition, FURS allows diagnosis and treatment of unexpected problems.

Flexible ureteroscopic lithotripsy for the treatment of upper urinary tract calculi in infants

We evaluated the clinical value of flexible ureteroscopic lithotripsy for the treatment of upper urinary tract calculi in infants. Fifty-five infants with upper urinary tract calculi were included in this study: 41 males and 14 females. Retrograde intrarenal surgery was performed by an 8 Fr/30 cm flexible ureterorenoscope (POLY®) combined with a holmium laser. CT scanning or radiography of the kidneys, ureters, and bladder region was performed one month after the operation to confirm the clearance of calculi. All the 55 infants with calculi in 74 sides underwent 66 flexible ureteroscopic lithotripsy procedures. The median operation time was 30 min. The median amount of flushing fluid was 500 mL. The stone-free rate after a single session treatment was 94.6%, within which 10 infants underwent simultaneous bilateral flexible ureteroscopy lithotripsy. Catheters were retained in 45 infants for 24-48 h after the operation. Continuous high fever due to reflux was present in two cases. Flushing fluid extravasation was found in one infant. Some patients with minor complications, such as mild hematuria, irritation symptoms, and low fever, recovered without treatment. The duration of hospitalization time after the operation was approximately 1-5 days. Flexible ureteroscopic lithotripsy is a safe, highly efficient, minimally invasive, and reproducible operation for removal of upper urinary tract calculi in infants. This technique is a convenient method for postoperative management of patients that enhances their rapid recovery. It is a promising option for therapy of infants ineffectively treated by extracorporeal shockwave lithotripsy.

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

OBJECTIVE

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

SUBJECTS AND METHODS

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

RESULTS

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

CONCLUSION

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

[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.

Tracking of radiation exposure in pediatric stone patients: The time is now

BACKGROUND

Despite the increasing incidence of pediatric nephrolithiasis, there is little data quantifying the radiation exposure associated with treatment of this disease. In this study, pediatric patients with nephrolithiasis who were managed at a single institution were identified, and the average fluoroscopy time and estimated radiation exposure associated with their procedures were reported.

METHODS

Stone procedures performed on pediatric patients between 2005 and 2012 were retrospectively identified. Procedures were classified as primary ureteroscopy (URS), stent placement prior to ureteroscopy (SURS), percutaneous nephrolithotomy (PCNL), and bilateral ureteroscopy (BLURS). Patient demographic information, stone size, stone location, number of radiographic images, and fluoroscopy times were analyzed.

RESULTS

A total of 152 stone procedures were included in the final analysis (92 URS, 38 SURS, eight BLURS and 14 PCNL). Mean patient age at time of stone treatment was 15.94 ± 4.1 years. Median fluoroscopy times were 1.6 (IQR 0.8-2.4), 2.1 (IQR 1.6-3.0), 2.5 (IQR 2.0-2.9), and 11.7 (IQR 5.0-18.5) minutes for URS, SURS, BLURS and PCNL, respectively. There was a moderate correlation between stone size and fluoroscopy time (r = 0.33). When compared with ureteroscopic procedures, PCNL was associated with a significantly higher fluoroscopy time (11.7 vs 2.1 min, P < 0.001). The estimated median effective dose was 3 mSv for ureteroscopic procedures and 16.8 mSv for PCNL. In addition to radiation exposure during treatment, patients in this cohort were exposed to an average of one (IQR1-3) CT scan and three (IQR 1-8) abdominal X-rays. No new malignancies were identified during the limited follow-up period.

CONCLUSIONS

Radiation exposure during treatment of pediatric stone disease is not trivial, and is significantly greater when PCNL is performed. Given the recommended maximum effective dose of 50 mSv in any one year, urologists should closely monitor the amount of fluoroscopy used, and consider the potential for radiation exposure when choosing the operative approach. Prospective studies are currently underway to elucidate precise dose measurements and localize sites of radiation exposure in children during stone treatment.

Medical expulsive treatment in pediatric urolithiasis

The frequency of stone disease in childhood ranges between 0.1-5 percent. Stone disease occurs as a result of enviromental, metabolic, anatomical, infectious and nutritional factors. Percutaneous nephrolitotomy, uretherorenoscopy, laparoscopic surgery, open surgery and extracorporeal shock wave lithothripsy are treatment alternatives for stone disease during childhood. However, these methods are not completely innocent. Some complications may occur after these procedures. These procedures are generally not cost- effective. Even invasive procedures have high success rates, so medical expulsive treatment modalities have become an alternative for a group of patients. Nonsteroidal anti- inflammatory drugs, antimuscarinic drugs, phospodiesterase type 5 inhibitors, steroids, calcium channel blockers and alpha blockers are treatment alterneatives used for this modality in the literature. The drug is chosen according to the location, size, and composition of the stone, recent technology, cost, surgeon's experience and surgeon's and the parents' preferences. In this review article the following topics will be discussed such as "Why medical expulsive treatment is needed during childhood? Which drug should be chosen for which stone type? How long should a treatment of urolithiasis last?

Are Adult Ureteroscopes Safe in the Management of Urolithiasis in a Pediatric Population?

INTRODUCTION

Debate remains regarding the optimal caliber of ureteroscopes in the management of pediatric urolithiasis, ranging from pediatric scopes to standard scopes. The aim of this study was to assess the safety and efficacy of stone management in a pediatric population using standard adult ureteroscopes.

METHODS

A retrospective review of all ureteroscopic procedures in patients under the age of 16 years was carried out. Standard adult 7.5 French semi-rigid and 6 French flexible ureteroscopes were used.

RESULTS

During the study period, 8 patients underwent 21 ureteroscopic procedures. Two patients had rigid ureteroscopy, seven had flexible ureterorenoscopy and one had a subsequent open procedure. No patients required ureteric dilation. Double J ureteric stents were utilized in 7 patients. There were no complications. All patients required extra corporeal shock wave lithotripsy. Stone clearance was achieved in all patients.

CONCLUSION

Our series demonstrates that, in skilled hands, adult ureteroscopes can be use safely for the treatment of urolithiasis in pediatric patients.

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.

Ureteroscopy for treatment of upper urinary tract stones in children: technical considerations

The incidence of pediatric urolithiasis is increasing. While many smaller stones may pass spontaneously, surgical therapy is sometimes warranted. Surgical options include shock wave lithotripsy, ureteroscopy, percutaneous nephrolithotomy, and open surgery. Ureteroscopy represents a minimally invasive approach, and it is increasingly being used to treat pediatric upper tract calculi. Ureteroscopy is performed under anesthesia and fluoroscopic guidance, with basket extraction or lithotripsy of the calculi. Technical considerations include active or passive ureteral dilatation, the use of ureteral access sheaths for larger stone burdens, and post-operative stent placement. The current pediatric literature suggests high success rates (equal to or surpassing shock wave lithotripsy) and low complication rates. However, concerns remain regarding feasibility in patients with variant anatomies and risk due to intra-operative radiation exposure.

[Clinical and biochemical characterization of childhood urolithiasis]

OBJECTIVES

Urolithiasis is rare in children, but the incidence has increased over the past few decades. This study aims at describing the clinical and biochemical characteristics, etiology, and treatment of urolithiasis in children.

METHODS

This was a retrospective study of all children under 16 years of age seen at the Bordeaux University Children's Hospital with a diagnosis of urolithiasis. The diagnosis was confirmed either radiologically or clinically by the expulsion of the stone.

RESULTS

A total of 186 children with a diagnosis of urolithiasis between 1994 and 2012 were included. The median age at diagnosis was 7.4 years. The male-to-female ratio was 1.9. The estimated annual incidence was around 5.5/100,000 children under 15 years of age in the past 5 years. The main presenting feature was nonspecific abdominal pain (71%). Metabolic calculi accounted for 48% of the patients with idiopathic hypercalciuria as the main cause. Genetic diseases accounted for 15% of cases. The proportion of infectious calculi was estimated at 33% and decreased in the past two decades. Stone fragments were sent for analysis in 86 children, and calcium oxalate was the major component (37%), followed by calcium phosphate (33%), purine (9%), and struvite (8%). At least 26% of patients experienced recurrence of stone passage.

CONCLUSION

This retrospective study highlighted changes in characteristics of pediatric urolithiasis over time. Childhood-onset urolithiasis requires complete etiological work-up so that a metabolic cause with a high risk of recurrence does not go unrecognized.

Retrograde intrarenal surgery for the treatment of renal stones in children: factors influencing stone clearance and complications

BACKGROUND

Retrograde intrarenal surgery (RIRS) is a known option for the treatment of upper tract calculi with an excellent success. However, the reports of RIRS in prepubertal children are limited. In this study, we evaluated the factors which affected the success rate and the complications of RIRS at renal stone treatment in childhood.

METHODS

We retrospectively reviewed the records of children under 14 years old who underwent RIRS for renal stone disease between January 2009 and December 2012. Patients' age, gender, body mass index (BMI), stone size, stone location, stone number, intraoperative complications, stone free status, postoperative complications were recorded.

RESULTS

There were 80 ureterorenoscopic procedures performed in 58 renal units of 47 children (23 males and 24 females). The patients' ages ranged from 8 months to 14 years (mean age 4.7 ± 3.4 years). There was a difference in the distribution of symptoms in age groups. UTI was higher in the 1-4 years age group, abdominal pain was seen mostly in children aged 5-14 years. Multiple stones (included staghorn stone) were noted in 60.4% of patients. In 27.6% of patients, ureteral stones were accompanied by renal stones in our series. In the infancy group, cystine and staghorn stones were more frequently seen, mostly bilateral. After a single ureteroscopic procedure for intrarenal stones in children, we achieved stone free status in 50.9% of the ureters (n=26). After the repeated sessions, the stone clearance rate reached to 85.1%.

CONCLUSION

Retrograde intrarenal surgery can be used as a first line therapy to treat renal stones in children. This is especially important if an associated ureteral stone is present that requires treatment; or in patients with cystinuria, which is not favorably treated with ESWL. Complications were seen more frequently in patients with cystine stones. Extravasation was noted more frequently in patients admitted with UTIs. There was a significant relationship between the conversion to open procedures and the age groups, with most procedures occurring in infancy. The parents should be informed about the probability of multiple procedures to achieve stone free status.

Ureteral complications after renal transplant in children: timing of presentation, and their open and endoscopic management

We retrospectively reviewed the records of 24 consecutive patients undergoing treatment for ureteral complications after RTx in the period 2001-2012 to determine the timing of presentation of the complications, and their open or endoscopic management. Three patients (12%) had a necrosis of the transplanted ureter soon after RTx. All required open urinary diversion in a native ureter. Ten cases (42%) developed ureteral obstruction. Time of presentation was variable mainly in relation to the underlying cause. Endoscopic treatment was successful in two cases with urinary stones and open surgery in two with mid-ureteral obstruction. Six patients had VUJ stenosis, three underwent open reimplantation, whereas temporary double-J stent placement was successfully performed in the remainder. Eleven patients (46%) had VUR. It seldom presented in the first year after RTx. Endoscopic treatment was attempted in all and was successful in all the six cases without vs. only one of the five with lower urinary tract pathology (p = 0.01). Endoscopic treatment is an option in patients with VUR in the absence of lower urinary tract pathology. It is an option also for the treatment of stones and can be attempted in case of VUJ stenosis. Ureteral necrosis always requires open treatment.

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.

Ureterolithotripsy in a paediatric population: a single institution's experience

This study presents one institution's experiences in ureterolithotripsy (URSL)--a particular endoscopic treatment modality. The incidence and prevalence of urolithiasis in the paediatric population continues to increase. However, the choice of the most appropriate treatment remains a challenging problem for paediatric surgeons. Between January 2006 and June 2013, the Department of Pediatric Surgery performed 157 URSLs. The patient population consisted of 126 children (60 girls and 66 boys) aged 10 months-17 years and having a body mass >8 kg. Dilatation of the pyelocalyceal system along with dilatation of the ureter above the concrement was present in all patients. Pneumatic, laser (Ho:YAG--pulsed laser), ultrasonic lithotripters with rigid, flexible ureteroscopes of 4.5/6 and 6.5/8 Ch were used. URSL was performed in 157 cases. During the first session, excellent results were obtained in 134 of 157 cases (85.3 %). In 15 cases (9.6 %), a second URSL was required. In five cases (3.2 %), URSL was performed a third time. A final stone-free rate of 98.1 % was obtained within the ureter. In three cases (1.9 %), complications were observed. In ten cases (6.37 %), a pigtail catheter was placed and retained in the ureter. URSL is a very good and effective endoscopic treatment for the removal of concrements localized in ureters. These concrements cause alterations in flow from the upper urinary tract in children. Because of the relatively small diameter and volume of the urinary tract in children aged <5 years, URSL in this population requires great precision, experience, and technical skill.

Factors affecting the outcome of extracorporeal shock wave lithotripsy for unilateral urinary stones in children: a 17-year single-institute experience

PURPOSE

Extracorporeal shock wave lithotripsy (ESWL) is a first-line treatment for pediatric urinary stone disease. We aimed to determine the factors affecting the outcome of ESWL for unilateral urinary stones in children.

MATERIALS AND METHODS

A total of 81 pediatric patients aged 0 to 16 years with urinary stones treated by ESWL from January 1995 through May 2012 were retrospectively reviewed. All patients were required to have unilateral urinary stone disease. Children who underwent other surgical procedures before ESWL were excluded. Outcomes evaluated after ESWL were the stone-free rate at 3 months after ESWL, success within a single session, and success within three sessions. Factors affecting the success within three sessions were also analyzed.

RESULTS

The final analysis was for 42 boys and 22 girls (mean age, 9.2±5.2 years). Of these 64 patients, 58 (90.6%) were treated by ESWL without other surgical procedures and 54 (84.4%) were successfully treated within three ESWL sessions. In the multivariate analysis, multiplicity (odds ratio [OR], 0.080; 95% confidence interval [CI], 0.012 to 0.534; p=0.009) and large stone size (>10 mm; OR, 0.112; 95% CI, 0.018 to 0.707; p=0.020) were significant factors that decreased the success rate within three ESWL sessions.

CONCLUSIONS

Most of the pediatric urinary stone patients in our study (90.6%) were successfully treated by ESWL alone without additional procedures. If a child has a large urinary stone (>10 mm) or multiplicity, clinicians should consider that several ESWL sessions might be needed for successful stone fragmentation.

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.

Treatment of pediatric renal stones in a Western country: a changing pattern

BACKGROUND

Over the last 10years the miniaturization of endoscopic instruments made minimally invasive procedures for kidney stones feasible even in children. The evolution in management of kidney stones in a tertiary care center in Europe is reported.

METHODS

Patients treated in our hospital for kidney stones from 2002 to 2011 were reviewed and group A (2002 to 2006) was compared with group B (2007 to 2011). The therapeutic options offered were Extracorporeal Shock Waves Lithotripsy (ESWL), Retrograde Intrarenal Surgery (RIRS), Percutaneous Lithotripsy (PCNL) and open surgery. Outcome measures were: first treatment chosen, stone free rate after a single procedure, and retreatment. Results were compared by chi-square test, with p <0.05 considered statistically significant.

RESULTS

333 patients, mean age 9.7years, were treated, 161 in group A and 172 in group B. ESWL was the first option in both groups, but decreased by 34% in group B vs A. In contrast, RIRS and PCNL increased by 17% and 16%, respectively, in group B vs group A. Open surgery was never required in primary lithiasis cases without associated malformations.

CONCLUSION

The advent of PCNL and RIRS has significantly changed the pattern of renal stone treatment in the pediatric age group. A progressive increase of endourologic minimally invasive procedures was recorded. Open surgery should be a very rare option.

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.

Comparison of a 4.5 F semi-rigid ureteroscope with a 7.5 F rigid ureteroscope in the treatment of ureteral stones in preschool-age children

The aim of this study was to compare the success and complication rates of a 4.5 F ureteroscope with a 7.5 F ureteroscope in the treatment of urolithiasis in preschool-age children. We retrospectively reviewed 69 ureteroscopy (URS) procedures in a pediatric population (40 boys, 29 girls). We divided the patients into two groups according to the type of ureteroscope used: group 1 (n = 42, Storz 7.5 F) and group 2 (n = 27, Wolf 4.5 F). We statistically compared all the procedures performed in both groups regarding patient age, complication rates, whether the procedure was therapeutic, and whether we used a guidewire. Additionally, in cases with ureteral stones, we also compared the stone clearance rate and the necessity of X-ray imaging between the two groups. The mean patient age was 56.04 months in group 1 and 47.48 months in group 2 (p = 0.057). The stone-free rate was 78.6 % in group 1 and 92.6 % in group 2 (p > 0.05). However, when we compared the stone-free rates for patients younger than 3 years, the rate was 66.7 % in group 1 and 93.8 % in group 2 (p < 0.05). The difference was not statistically significant for patients between the ages of 4 and 7 years. The success and failure rates revealed better outcomes for treatment of ureteral stones with a 4.5 F ureteroscope. We recommend the use of the mini-ureteroscope, especially in infants and preschool-age children.

Contemporary management of ureteral stones

CONTEXT

Ureteral calculi represent a common condition that urologists encounter in everyday practice. Several treatment options are available for calculi that do not pass spontaneously or are unlikely to do so.

OBJECTIVE

In this nonsystematic review, we summarize the existing data on contemporary management of ureteral stones focusing on medical expulsive therapy (MET) and different treatment modalities.

EVIDENCE ACQUISITION

A PubMed search was performed. We reviewed the recent literature on the management of ureteral calculi. Articles were considered between 1997 and 2011. Older studies were included selectively if historically relevant.

EVIDENCE SYNTHESIS

For stones that do not pass spontaneously or with MET, shock wave lithotripsy (SWL) and ureteroscopy (URS) are the most common and efficient treatment modalities. Both techniques have obvious advantages and disadvantages as well as different patterns of complications. For select cases or patients, other modalities may be useful.

CONCLUSIONS

Ureteral stones of up to 10mm and eligible for observation may be offered MET. For most ureteral calculi that require treatment, advances in SWL and URS allow urologists to take a minimally invasive approach. Other more invasive treatments are reserved for select "nonstandard" cases.

Effectiveness of ultrasonography in the postoperative follow-up of pediatric patients undergoing ureteroscopic stone manipulation

OBJECTIVES

To evaluate the effectiveness of ultrasonography and to determine whether ionizing radiation is necessary in the postoperative follow-up of children undergoing ureteroscopy.

METHODS

We reviewed the charts of 49 children who underwent 51 ureteroscopic procedures for ureteral calculi. Renal ultrasound and intravenous urography were performed in all patients at 3 months after surgery for postoperative evaluation.

RESULTS

In three cases, stones migrated to the kidney. Retrograde intrarenal surgery was performed in two patients and one patient required shockwave lithotripsy to become stone-free. Fourty-six children were completely stone-free and 3 had residual fragments on plain film in the postoperative 3 month. The sensitivity, specificity, negative and positive predictive values of ultrasonography for detecting hydronephrosis were 85.7, 100, 97.7 and 100%, respectively. Two patients under observation and three patients under medical expulsive therapy had resolution of hydronephrosis on follow-up. One patient required ureteroscopy for residual obstructing fragments.

CONCLUSIONS

Ultrasonography has limited accuracy for detecting residual ureteral stones, but it is a highly specific and reasonably sensitive test for detecting hydronephrosis. A combination of ultrasonography and plain film is a safe and effective imaging procedure in postoperative follow-up of children undergoing ureteroscopy.

Open surgical management of pediatric urolithiasis: A developing country perspective

Objectives

To describe decision factors and outcome of open surgical procedures in the management of children with stone.

Materials and Methods

Between January 2004 and December 2008, 3969 surgical procedures were performed in 3053 children with stone disease. Procedures employed included minimally invasive techniques shockwave lithotripsy (SWL), percutaneous nephrolithotomy (PCNL), ureterorenoscopy (URS), perurethral cystolithotripsy (PUCL), percutaneous cystolithotripsy (PCCL), and open surgery. From sociomedical records demographics, clinical history, operative procedures, complications, and outcome were recorded for all patients.

Results

Of 3969 surgeries, 2794 (70%) were minimally invasive surgery (MIS) techniques to include SWL 19%, PCNL 16%, URS 18.9%, and PUCL+PCCL 16% and 1175 (30%) were open surgeries. The main factors necessitating open surgery were large stone burden 37%, anatomical abnormalities 16%, stones with renal failure 34%, gross hydronephrosis with thin cortex 58%, urinary tract infection (UTI) 25%, and failed MIS 18%. Nearly 50% of the surgeries were necessitated by economic constraints and long distance from center where one-time treatment was preferred by the patient. Stone-free rates by open surgeries were pyelolithotomy 91%, ureterolithotomy 100%, and cystolithotomy 100% with complication rate of upto 3%.

Conclusions

In developing countries, large stone burden, neglected stones with renal failure, paucity of urological facilities, residence of poor patients away from tertiary centers necessitate open surgical procedures as the therapy of choice in about 1/3rd of the patients. Open surgery provides comparable success rates to MIS although the burden and nature of disease is more complex. The scope of open surgery will remain much wide for a large population for considered time in developing countries.

Clinical practice: surgical approaches to urolithiasis in children

The incidence of urolithiasis in children is increasing. Adequate knowledge of treatment modalities and surgical options is therefore essential for every pediatrician. Surgical approaches to urolithiasis in children continue to evolve with advancements in technology and sophistication of current equipment and techniques. Perhaps the most significant development in new techniques is the advent of robotic-assisted laparoscopy. This review, for the general pediatrician, summarizes the most recent pediatric data and guidelines for surgical approaches to treatment of urolithiasis.

Modern applications of ureteroscopy for intrarenal stone disease

PURPOSE OF REVIEW

Ureteroscopy continues to improve as a method for management of intrarenal stone disease. The development of new technologies and enhanced application of existing therapies is expanding the indications of ureteroscopy for the management of renal calculi.

RECENT FINDINGS

Improvements in image quality have been achieved with the adoption of digital ureteroscopes. Modifications of standard ureteroscopic techniques and improvements in surgical skill training are also being made. Ureteroscopy is demonstrated to be well tolerated and efficacious for the management of intrarenal calculi in multiple-patient populations and is also cost-efficient.

SUMMARY

The indications for ureteroscopic management of renal calculi are expanding, and this technique is quickly being adopted as a routine option for the management of intrarenal stone disease.

Genitourinary intervention in children

The role of interventional radiology in paediatric nephrology and urology is gradually increasing. Some procedures (such as renal biopsy) are best performed using radiological techniques, some (such as ureteric stenting) by either radiologists or urologists, depending on clinical circumstances, and some (such as percutaneous nephrolithotomy) are usually performed jointly by urologists and interventional radiologists. This paper briefly reviews the main non-vascular interventional radiology techniques used in the genitourinary tract in children. Common procedures such as renal biopsy and nephrostomy and related procedures are emphasised.

Tubeless mini percutaneous nephrolithotomy in infants and preschool children: a preliminary report

PURPOSE

We retrospectively analyzed the outcomes of tubeless mini percutaneous nephrolithotomy in infants and preschool children, and compared them with age matched controls who underwent nephrostomy drainage.

MATERIALS AND METHODS

A total of 28 renal units in 26 children were operated on for stone disease using the mini percutaneous nephrolithotomy technique. Holmium laser and pneumatic lithotriptor were used for stone fragmentation. Children who underwent complete stone removal and had a clear nephrostomy tract only had a ureteral catheter placed. Those with residual stones or bleeding from the nephrostomy tract underwent nephrostomy drainage. We compared both groups with regard to patient and stone characteristics, and postoperative findings.

RESULTS

A total of 12 renal units had only a ureteral catheter for diversion, while 16 had nephrostomy drainage. Mean respective ages of the stentless and nephrostomy groups were 3 (range 0.58 to 6) and 3.3 years (1.5 to 6). Mean respective stone burdens were 192 (range 100 to 400) and 416 (775 to 1,380) mm2. Surgery and fluoroscopy times were shorter in the tubeless group. Complication rates were higher (6 of 14 vs 0 of 12) and duration of hospitalization was longer (4.9 [range 3 to 14] vs 3.1 days [2 to 6]) in the nephrostomy group. Stone-free rates were 91.6% in the tubeless and 78.5% in the nephrostomy groups.

CONCLUSIONS

Tubeless percutaneous nephrolithotomy was observed to be a safe option for selected children with stone disease. The success and safety of tubeless percutaneous nephrolithotomy depends on patient selection criteria, including low volume and infection-free stones that are removed completely without any bleeding from the access tract.

Operative management of pediatric urolithiasis

Surgical management of urinary stones in children remains challenging due to the smaller caliber of the urinary tract. Specific instruments have been designed to overcome some of the issues related to pediatric stone management. Endoscopic and percutaneous modalities for stone management have been shown to be as safe and effective in providing stone clearance in children as in adults. Technologies that have been shown to be safe in adults are being miniaturized for use in children. The current literature regarding pediatric urolithiasis was reviewed in an effort to identify trends in operative management. Additionally, techniques used successfully at our institution are described. Although not an exhaustive review of all available modalities and instruments, this review will provide an overview of the current techniques for the management of pediatric urolithiasis.

Management of multiple stones in a single session using minimally invasive methods in infants with renal failure: renal salvage

The goal in the treatment of stone disease causing infantile obstructive uropathy is to obtain a quick resolution of the obstruction using the least invasive treatment modality available and rendering the patient stone-free, if possible. Two infants with bilateral kidney stones, the first of whom also had ureteral stone, were referred to our clinic with acute renal failure and were treated successfully in a single session using minimally invasive methods. In this report, we discuss the management of these two cases, aged 9 and 26 months, which resulted in favorable outcomes.

Safety and efficacy of percutaneous nephrolithotomy in infants, preschool age, and older children with different sizes of instruments

OBJECTIVES

To compare the morbidity and success rates among different age groups of children undergoing percutaneous nephrolithotomy (PCNL) using adult- or pediatric-sized devices. PCNL for renal stones in children may present problems because of small size, mobility of the pediatric kidney, and the small size of the collecting system.

METHODS

Patients were categorized into 2 age groups: those < or =7 years old at the time of PCNL (group 1, n = 17 [38.6%]), and those 8-16 years old (group 2, n = 27 [61.4%]). Group 2 children were further divided into subgroups according to the use of pediatric- (group 2a, n = 12 [27.3%]) or adult-sized devices (group 2 b, n = 15 [34.1%]).

RESULTS

Mean patient age was 4.1, 11.7, and 13.2 years in groups 1, 2a, and 2b, respectively. Fluoroscopy time, time to access the collecting system, operative time, and average postoperative hospital stay did not differ between the groups. However, hemoglobin decrease, bleeding during surgery, and blood transfusion rate was higher in group 2b. Stones were completely cleared in 82.4%, 83.3%, and 81.3% patients, and these percentages increased to 94.1%, 91.7%, and 93.7% with adjunctive shock wave lithotripsy and ureterorenoscopy in groups 1, 2a, and 2b, respectively.

CONCLUSIONS

Endourologic intervention in children usually requires instruments specific for preschool age; however, in older children with dilated collecting system, the use of adult instruments and techniques may achieve equal results.