Prediction model for serious complications after primary laparoscopic pyeloplasty in children: is it a useful tool?

Since the first description of laparoscopic pyeloplasty (LP) in children (1), this approach has been widely used in the treatment of pediatric ureteropelvic junction obstruction (UPJO), and it has been confirmed as a feasible and efficient technique, even in infants under ≤10 kg (2) or younger than 2 years of age (3-5). Despite of this, the data about safety of LP in these patients, is still limited. There have only been a few relevant studies that have put forward a simple description and have reported a broad complication rate of 6.7–37.5% (4,6-11). Nevertheless, no prior publications with a large series have focused on the analysis of complications of primary LP and the impact factors in order to create a prediction model for negative outcomes.

We have read with great interest the contribution done by Li et al., in their study: “Development of the prediction model for negative outcomes after primary laparoscopic pyeloplasty in children: a retrospective study of 535 patients” (12).

The paperwork of our colleagues is relevant because it is one of the first studies that develop a prediction model to quantify the probability of negative outcomes after LP. In addition, their work presents a large number of cases, which gives great validity to its results. Then, this prediction model could lead clinicians to offer a more individualized treatment approach, minimizing the likelihood of adverse events after laparoscopic correction of UPJO. Nevertheless, we would like to add some considerations to their paper.

First, the authors conclude that the low weight, the increased preoperative pelvic diameter, and the difficulty of inserting double-J (DJ) stents, are risk factors for an unfavorable evolution after LP. On the other hand, authors affirm that externalized pyeloureteral stent was more prone to serious postoperative complications than DJ drainage. But authors do not compare both catheters under the same conditions. They only insert the external catheter if the DJ does not progress adequately to the bladder. So, it is possible that this group of patients have an associated ureterovesical stenosis or an iatrogenic injury at that level during the attempted placement of the DJ stent, which obviously worsens the prognosis.

The Hospital Sant Joan de Déu experience is the opposite: higher pelvis diameter and the use of external stents were protective risk factors while older (and heavier) patients had higher risk of complications (13). So, which are the real risk factors for complications after primary LP in children? Is it possible to find global risk factors?

Li et al. described three limitations of their model: firstly, it is single center study that can lead to potential selection bias hardly avoidable. Secondly, seven surgeons performed operations separately, so bias was unavoidable because these physicians had slightly different preferences and approaches to some details during the surgery. Thirdly, it was a retrospective study (12). It is a bit contradictory to consider these limitations or weaknesses of the study: on the one hand being a single center, but on the other hand having multiple surgeons. What is the intention of the authors? Getting a tool for one surgeon or a small group of surgeons in a single environment? Or creating a tool that can be useful to any surgeon in the world in his own center? Is it possible to achieve the latter? We need larger series and multicentric randomized prospective studies to find this answer.

It would be very interesting to know the real risk factors. Thus, the pediatric urologist could improve his surgical strategy (adapted to the characteristics of the patient) and the success of the results. However, we consider relevant to include other possible risk factors in the univariate and multivariate model described by Li et al. (12). Those factors could have also distorted the general results of this work. For example, the preoperative obstruction presentation or other intraoperative problems.

In conclusion, we congratulate the authors for this risk factors study of LP. This work demonstrates that this technique is a safe and effective procedure in children, with a low rate of complications. An improved global prediction model could help clinicians make individualized assessments of cases and give them more specific support. At this time, the attention should be focused on assessing whether the application of this kind of tools in the future modifies the prognosis of patients.

Acknowledgments

Funding: None.

Footnote

Provenance and Peer Review: This article was commissioned by the editorial office, Translational Andrology and Urology. The article did not undergo external peer review.

Conflicts of Interest: The authors have completed the ICMJE uniform disclosure form (available at https://tau.amegroups.com/article/view/10.21037/tau-23-72/coif). The authors have no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

References

1. Peters CA, Schlussel RN, Retik AB. Pediatric laparoscopic dismembered pyeloplasty. J Urol 1995;153:1962-5. [Crossref] [PubMed]
2. Neheman A, Noh PH, Piaggio L, et al. The role of laparoscopic surgery for urinary tract reconstruction in infants weighing less than 10 kg: a comparison with open surgery. J Pediatr Urol 2008;4:192-6. [Crossref] [PubMed]
3. Cascio S, Tien A, Chee W, et al. Laparoscopic dismembered pyeloplasty in children younger than 2 years. J Urol 2007;177:335-8. [Crossref] [PubMed]
4. Turner RM 2nd, Fox JA, Tomaszewski JJ, et al. Laparoscopic pyeloplasty for ureteropelvic junction obstruction in infants. J Urol 2013;189:1503-7. [Crossref] [PubMed]
5. Simforoosh N, Abedi A, Hosseini Sharifi SH, et al. Comparison of surgical outcomes and cosmetic results between standard and mini laparoscopic pyeloplasty in children younger than 1 year of age. J Pediatr Urol 2014;10:819-23. [Crossref] [PubMed]
6. Badawy H, Saad A, Fahmy A, et al. Prospective evaluation of retroperitoneal laparoscopic pyeloplasty in children in the first 2 years of life: Is age a risk factor for conversion? J Pediatr Urol 2017;13:511.e1-4. [Crossref] [PubMed]
7. Mei H, Zhao X, Li D, et al. Comparison of transumbilical multiport and standard laparoscopic pyeloplasty in children: Mid-term results at a single center. J Pediatr Surg 2017;52:473-7. [Crossref] [PubMed]
8. Blanc T, Muller C, Abdoul H, et al. Retroperitoneal laparoscopic pyeloplasty in children: long-term outcome and critical analysis of 10-year experience in a teaching center. Eur Urol 2013;63:565-72. [Crossref] [PubMed]
9. Silay MS, Spinoit AF, Undre S, et al. Global minimally invasive pyeloplasty study in children: Results from the Pediatric Urology Expert Group of the European Association of Urology Young Academic Urologists working party. J Pediatr Urol 2016;12:229.e1-7. [Crossref] [PubMed]
10. Vicentini FC, Dénes FT, Borges LL, et al. Laparoscopic pyeloplasty in children: Is the outcome different in children under 2 years of age? J Pediatr Urol 2008;4:348-51. [Crossref] [PubMed]
11. He Y, Song H, Liu P, et al. Primary laparoscopic pyeloplasty in children: A single-center experience of 279 patients and analysis of possible factors affecting complications. J Pediatr Urol 2020;16:331.e1-331.e11. [Crossref] [PubMed]
12. Li J, Li Z, He Y, et al. Development of the prediction model for negative outcomes after primary laparoscopic pyeloplasty in children: a retrospective study of 535 patients. Transl Androl Urol 2022;11:1680-90. [Crossref] [PubMed]
13. Pérez-Bertólez S, Martín-Solé O, García-Aparicio L. Comparison between mini-laparoscopy, conventional laparoscopy and open approach for ureteropelvic junction obstruction treatment in children. Scand J Urol 2021;55:307-12. [Crossref] [PubMed]