Minimally Invasive Surgical Approaches to Kidney Stones in Children

Factors associated with the stone-free status after retrograde intrarenal surgery in children

INTRODUCTION

Paediatric urolithiasis has a recurrent nature because it is frequently associated with metabolic or anatomical disorders or infectious conditions. The rising incidence of the disease with its recurrent nature emphasises the need for minimally invasive therapeutic options. In this study, we aimed to evaluate efficacy and factors affecting the success of retrograde intrarenal surgery (RIRS) in children.

MATERIALS AND METHODS

Patients who underwent RIRS were evaluated retrospectively. Two different flexible ureteroscopes (F-URS) were used (7.5F F-URS and 7.95F with a 4.9F bullet-shaped tip). Irrespective of size, all residual fragments were considered as failure. Age, stone size, stone localisation, Hounsfield Unit (HU), stone-free rate (SFR) and complications were evaluated.

RESULTS

Forty-six patients (29 boys and 17 girls) with a median age of 70.5 months (6-214 months) were treated with RIRS between August 2014 and November 2019. The median operative time was 60 minutes (45-120 minutes). The median follow-up was 26 months (3-65 months). Fourteen patients had lower pole and 10 patients had multiple stones. Ureteral access sheath (UAS) was used in 16 (35%) patients. SFR was 61%. The median number of general anaesthesia was 2 (min 1, max 5). Auxiliary semirigid URS, PCNL and repeat RIRS were required in 4, 6 and 5 patients, respectively. Two patients had postoperative febrile urinary tract infection (UTI) as a complication. Age was associated with post-operative febrile UTI. Presence of stones with HU lower than 700, being operated 4.9F F-URS and without UAS were associated with better SFR.

CONCLUSIONS

RIRS is a minimally invasive method with low complication rates in the treatment of childhood stone disease. Higher stone-free rates are obtained in low HU stones and cases in which we used 4.9 F tip F-URS.

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

Background

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

Methods

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

Results

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

Conclusions

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

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

BACKGROUND

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

PATIENTS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

A new nomogram for prediction of outcome of pediatric shock-wave lithotripsy

INTRODUCTION

Despite the fact that shock-wave lithotripsy (SWL) remains a very good treatment option for smaller stones, it is being challenged by endourologic treatment modalities, which offer similar or even higher success rates in a shorter time, with minimal morbidity and invasiveness. The present study aimed to bring a new and practical insight in order to predict the outcomes of pediatric SWL and to provide objective information about pediatric SWL outcomes.

OBJECTIVE

To design a nomogram for predicting the outcomes of pediatric shock-wave lithotripsy.

STUDY DESIGN

The study was conducted with a retrospective design and included 402 renal units who underwent SWL between January 2009 and August 2013. Patients with known cystine stone disease and cystinuria, with internal or external urinary diversion, were excluded. Analysis was performed on 383 renal units. Postoperative imaging was performed by plain abdominal graphy and ultrasonography with 3-month intervals. Patients who were completely free of stones were considered to be a success and statistical analysis was done regardingly Multivariate analysis was conducted by logistic regression analysis and a nomogram was developed.

RESULTS

The male/female distribution was 216/167, with a mean age of 48 ± 40 months and a mean stone size of 9 ± 3.5 mm. The overall stone-free rate was 70% (270/383) and efficacy quotient was 0.57. Mean follow-up was 11 ± 11 months (3-54 months). The number of shock waves and amplitude of energy were higher in failed cases. Multivariate analysis showed that gender, stone size, number of stones, age, location of the stone, and history of previous intervention were found to be the independent prognostic factors for assessing the stone clearance rates. A nomogram was developed using these parameters. In this nomogram, the points achieved from each parameter are summed and total points correspond to the risk of failure in percent.

DISCUSSION

A previous nomogram study by Onal et al. showed that younger age (<5 years), smaller stone burden (<1 cm), absence of previous stone treatment history, single stone, pelvis or upper ureter location (in girls) were favorable prognostic factors for successful outcome. As being the first pediatric study, it had some shortcomings. The study included 381 patients within a time period of 16 years. The present study included a similar number of cases within a 4-year period, which may reflect more homogeneity of data collection. Another issue is concern about the practical use of that nomogram. It constitutes two pages, which is a limiting factor for daily use. From a statistical point of view, they performed 200 bootstrapings with the aim of internal validation, which is less than the ideal number of 1000 bootstrapings, which was performed in the present nomogram. The presented nomogram is more practical, in that the pre-operative factors can be placed on the nomogram, the points can be added up and the parents can be given the approximate percentage of predicted stone-free rate after a single session. The expected treatment modality shown to the parents and patients ought to be the least minimally invasive, have the highest success rate, the least complication rate, and show the efficacy in one procedure at a time within the shortest period. However, SWL does not completely meet these criteria. The results gained from the present critical analysis of SWL in children, which was based on a strict definition of success, showed that outcome after a single session is not that good. Therefore, defining the patients who will benefit the most became one of the main issues. A more objective and skeptical look at SWL data enabled a nomogram to be developed that brings a new and practical insight in order to predict the outcomes of pediatric SWL.

CONCLUSION

In most of the pediatric stone cases, SWL is the first-line treatment option. However, it is wise to define the patients who will benefit the most. Therefore, nomograms can be useful for this purpose. The nomogram in the present study revealed that gender, stone size, number of stones, age, location of the stone, and history of previous intervention were found to be the independent prognostic factors for assessing the stone clearance rates. This nomogram can practically be used to inform the parents, and for proper patient selection for SWL.

Does aging affect the outcome of percutaneous nephrolithotomy?

To investigate whether aging affects surgical outcomes by comparing the results of two patient groups undergoing PNL: those over 60 and those under 60. A retrospective screen was made for patients undergoing conventional PNL surgery for renal stones performed in two separate centers between 2010 and 2013. 520 patients included were classified into age groups: patients aged 18-59 comprised Group-1 and those aged over 60 comprised Group-2. Those between 60-69 years (sexagenarian) were assigned to Group-2a; 70-79 years (septuagenarian) to Group-2b; and 80-89 years (octogenarian) to Group-2c. Patients' demographic characteristics (accompanying comorbidities, ASA scores, body mass indices and stone size) and perioperative values (duration of surgery and hospital stay, success and complication rates) were compared between the groups. Mean stone size was similar in groups (30.1 ± 15.5 vs. 31.5 ± 15.4 mm, p = 0.379). The mean ASA value for the patients in Group-1 was 1.61; significantly lower than that in the other groups (p = 0.000). The level of accompanying comorbidities in Group-1 was significantly lower than that of the other groups (p = 0.000). The mean duration of surgery, postoperative hematocrit drop, complication and success rate were statistically similar in Groups 1 and 2 (p = 0.860, p = 0.430, p = 0.7, and p = 0.66, respectively). The duration of hospital stay was significantly shorter in the patients in Group-1 compared to those in Group-2 (p = 0.008). In experienced hands, PNL can be safely and reliably performed in the treatment of renal stones in elderly patients.

Comparison of shockwave lithotripsy and microperc for treatment of kidney stones in children

PURPOSE

We aimed to compare the outcomes of microperc and shockwave lithotripsy (SWL) for treatment of kidney stones in children.

PATIENTS AND METHODS

The medical records of 145 patients under the age of 15 years with opaque and single kidney stones treated with either SWL or microperc were retrospectively reviewed. Both groups were compared in terms of fluoroscopy and operative time, re-treatment, complications, success rate, and secondary and total number of procedures.

RESULTS

Microperc and SWL were performed on 37 and 108 pediatric patients, respectively. The mean age of the patients was 5.91±4.03 years (1-15) and 8.43±4.84 (1-15) years in the SWL and microperc groups, respectively (P=0.004). The mean stone size was 11.32±2.84 (5-20) mm in the SWL group and 14.78±5.39 (6-32) mm in the microperc group (P<0.001). In the SWL group, 31 (28.7%) patients underwent a second SWL session and 6 (5%) had a third session. Finally, 95 (88%) patients were stone free at the end of the SWL sessions. In the microperc group, the stone-free rate was 89.2% in a single session (P=0.645). The mean duration of hospitalization was 49.2±12.3 (16-64) hours in the microperc group and 8.4±2.3 (6-10) hours per one session in the SWL group (P<0.001). The fluoroscopy time was significantly longer in the microperc group compared with the SWL group (147.3±95.3 seconds vs 59.6±25.9 seconds, P<0.001). The rate of requirement for an auxiliary procedure was higher in the SWL group than in the microperc group. The overall complication rates for the microperc and SWL groups were 21.6% and 16.7%, respectively (P=0.498).

CONCLUSIONS

The results of our study demonstrate that microperc provides a similar stone-free rate and a lower additional treatment rate compared with SWL in the treatment of kidney stone disease in children.