Safety and Efficacy of Pyeloplasty in Children aged less than 1 year: Experience from a Tertiary Care Hospital of North India

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The timing of pyeloplasty in infants under the age of one is controversial secondary to issues of anesthetic safety, technical complexity, and spontaneous resolution. Materials and Methods This prospective cohort study assessed the safety and effectiveness of pyeloplasty in 62 infants less than 12 months old. Inclusion criteria were obstructed hydronephrosis or compromised drainage, and exclusion criteria included bilateral UPJO requiring synchronous intervention, solitary kidney, or concomitant anomalies. Open or laparoscopic Anderson–Hynes pyeloplasty was done, with follow-up standardized to include ultrasonography and diuretic renography. Results Mean age at surgery was 6.2 ± 2.8 months. Postoperative complications in 11.3% of infants were primarily minor, with only one requiring re-intervention. Differential renal function also significantly improved from 32.5 ± 6.8% preoperatively to 39.1 ± 7.2% by 12 months (p < 0.001). Success of the operation was seen in 95.2%, with Kaplan–Meier survival at one year and three years at 98% and 95%, respectively, being intervention-free. Conclusions Early pyeloplasty is safe, effective, and with significant functional recovery, especially in infants operated on before the age of 6 months. Pyeloplasty infants hydronephrosis ureteropelvic junction obstruction renal function Figures Figure 1 Figure 2 Introduction Ureteropelvic junction obstruction (UPJO) is the most prevalent etiology of hydronephrosis in children and is responsible for almost 35–45% of prenatally diagnosed urinary tract anomalies [ 1 ]. Improvement in antenatal ultrasonography has resulted in increased detection of hydronephrosis, with many such cases later confirmed as UPJO in the neonatal or early infant stage [ 2 ]. Even though some instances of hydronephrosis are spontaneously resolving and self-limiting, persistent or severe obstruction carries considerable risks of progressive renal injury, recurrent UTIs, and compromised renal growth [ 3 ]. Therefore, treatment of UPJO in early life has remained a longstanding area of interest in clinical and academic practice in pediatric urology. The optimal timing of surgical repair, especially pyeloplasty, in infants under one year of age continues to be a matter of significant controversy. Clinicians traditionally waited until after the first year of life because of concerns for anesthetic safety, technical difficulties in the tiny infant, and the possibility of spontaneous resolution [ 4 ]. Yet, mounting evidence has proved that delayed intervention can allow for irreversible renal parenchymal damage, particularly in severe obstruction [ 5 ]. On the other hand, early infant pyeloplasty has the theoretical advantage of maintaining renal function during a phase of accelerated nephrogenesis and renal maturation [ 6 ]. This balance between these two opposing risks supports clinical controversy. Several retrospective and prospective investigations have tried to address the safety and efficacy of pyeloplasty early on. Complication rates involving anastomotic leak, urinary tract infection, or restenosis have been reported to be similar for infants operated on before and after 12 months of age, according to some reports [ 7 ]. In addition, advances in anesthetic monitoring, neonatal intensive care, and surgery, such as the availability of smaller instruments and magnification, have optimized the safety profile of early surgery [ 8 ]. However, heterogeneity of study populations, surgical technique (open vs minimally invasive), and follow-up strategies reduces the external validity of these data [ 9 ]. Another question that has not been answered is the long-term functional results of early pyeloplasty. Whereas some scientists have described dramatic improvement in differential renal function (DRF) after operation in infants [ 10 ], others have mentioned stabilization and not dramatic improvement, especially when the initial function was already significantly compromised [ 11 ]. The heterogeneity of renal recovery highlights the need for the determination of prognostic factors that can identify which infants are likely to gain the most from early treatment. In addition, although functional imaging tests like diuretic renography are very useful, they are probably less accurate in extremely young babies, making clinical decision-making more challenging [ 12 ]. There is still limited high-quality, sufficiently powered research exclusively in infants under one year of age. Most of the existing data derive from mixed-age series where infants are only a subset. Accordingly, there is minimal evidence of whether pyeloplasty done in the first year of life has any special risks or advantages over later intervention [ 13 ]. In addition, most previous studies focus on perioperative safety or radiological results, but not on both in an inclusive way. Such compartmentalization creates an important knowledge deficit on the entire safety-efficacy balance of pyeloplasty in this population. Clinically, the choice to move forward with early pyeloplasty needs to be weighed carefully in terms of parental distress, consumption of healthcare resources, and ultimate prognosis. Parents of infants with severe hydronephrosis are frequently faced with conflicting advice, which contributes to decisional distress [ 14 ]. Additionally, healthcare systems need to balance the expense of serial imaging and extended surveillance against the advantages of definitive early intervention. Accordingly, evidence-based advice is crucial to counsel both families and clinicians. Objectives The aim of this research was to systematically analyze the efficacy and safety of pyeloplasty in children younger than one year of age. It attempted to study perioperative results, such as hospitalization and complication rates, along with functional efficacy by radiological as well as clinical parameters. Methods Study Design This was a prospective cohort study from one of the tertiary care pediatric surgery centers of North India. All consecutive infants younger than 12 months who were operated on with pyeloplasty for ureteropelvic junction obstruction (UPJO) were included. The design permitted systematic perioperative data collection, standardized postoperative follow-up, and objective evaluation of both safety and efficacy outcomes. Human Ethics and Consent to Participate The study was performed according to the Declaration of Helsinki. Approval was received from the Institutional Ethics Committee ( IEC-SKIMS/2022 ) before the start of the study. Written informed consent was obtained from the parents and/or legal guardians of all infants before enrollment and surgery. Inclusion Criteria The inclusion criteria were all infants under 12 months of age at surgery, those with radiologically confirmed hydronephrosis having an anteroposterior renal pelvic diameter of > 20 mm or progressive dilatation on follow-up ultrasonography, and those with obstructed drainage or differential renal function of < 40% on diuretic renography. Exclusion Criteria Exclusion criteria were infants with bilateral ureteropelvic junction obstruction that needed surgery at the same time, known associated major urological abnormalities such as posterior urethral valves or vesicoureteral reflux, solitary functioning kidney infants, and those with suboptimal or incomplete follow-up information. Diagnostic Evaluation A uniform diagnostic protocol was used in all patients before surgery. Initial assessment consisted of a renal and bladder ultrasound to determine the grade of hydronephrosis based on the Society for Fetal Urology (SFU) classification. Diuretic renography with technetium-99m mercaptoacetyltriglycine (99mTc-MAG3) was done to establish obstruction and measure differential renal function (DRF). In selected cases, magnetic resonance urography was used to offer anatomical information and rule out crossing vessels. Laboratory tests consisted of serum creatinine and urinalysis to detect preoperative infection. Surgical Technique All of the pyeloplasties were done under general anesthesia with endotracheal intubation. The surgical technique was at the surgeon's discretion and the infant's anatomy. Open pyeloplasty through a short flank incision was routine, and laparoscopic dismembered pyeloplasty was provided for selected infants weighing > 5 kg. In both methods, the Anderson–Hynes dismembered pyeloplasty was carried out, with careful spatulation of the ureter and watertight anastomosis with fine absorbable sutures. At the discretion of the surgeon, a trans anastomotic stent or external nephrostomy tube was left in place. Perioperative antibiotic prophylaxis was given by institutional policy. Outcome Measures The main outcomes were obstruction as evidenced by augmented drainage pattern on diuretic postoperative renography, and recovery function as stabilization or improvement of differential renal function. The secondary outcomes comprised intraoperative factors like time of operation, blood loss, and intraoperative complications, and postoperative outcomes such as complication rates scored using Clavien–Dindo classification, hospital stay, readmission, re-intervention, and general rate of success. Follow-Up Protocol Patients were examined at 1 month, 3 months, 6 months, and then once a year for a maximum of 3 years. At each visit, clinical assessment and ultrasonography were conducted to evaluate hydronephrosis. Diuretic renography was performed at 6 months and 12 months after surgery, or sooner if there was a symptom or imaging evidence of obstruction. Renal function and status regarding complications were recorded at each interval. Statistical Analysis All information was entered into a prospectively kept database. Continuous variables were presented as mean ± SD or median with IQR as relevant. Categorical variables were described in frequencies and percentages. The paired t-test or Wilcoxon signed-rank test was employed to compare preoperative with postoperative renal function. The Kaplan–Meier survival estimate was utilized to calculate intervention-free survival. Logistic regression analysis was used to determine predictors of surgical success and complications. Statistical significance was defined as a p-value < 0.05. Statistical analysis was conducted with SPSS version 22. Results Baseline Characteristics A total of 62 infants (male: 38, female: 24) underwent pyeloplasty during the study period. The mean age at surgery was 6.2 ± 2.8 months (range: 2–11 months). The left kidney was affected in 37 cases (59.7%), the right kidney in 25 cases (40.3%), and bilateral obstruction requiring staged intervention in 3 cases (4.8%). Preoperative imaging detected gross hydronephrosis (SFU grade 3–4) in 54 infants (87.1%), with an anteroposterior pelvic diameter of 28.6 ± 6.1 mm. The preoperative differential renal function averaged 32.5 ± 6.8%. Table 1 outlines the 62 infants treated with pyeloplasty and their baseline characteristics. The average age was 6.2 months, with a male-to-female ratio of 38:24. Obstruction was more frequently left-sided than right-sided. The majority of babies had severe hydronephrosis (87.1%), with an average anteroposterior diameter of 28.6 mm and an average preoperative DRF of 32.5%. Table 1 Baseline demographic and clinical characteristics of infants (n = 62) Variable Value Mean age at surgery (months) 6.2 ± 2.8 (range: 2–11) Gender (Male: Female) 38:24 Laterality (Left: Right) 37:25 Bilateral obstruction (staged) 3 (4.8%) Severe hydronephrosis (SFU 3–4) 54 (87.1%) Mean AP diameter (mm) 28.6 ± 6.1 Mean preoperative DRF (%) 32.5 ± 6.8 Intraoperative Outcomes The median operative time was 76 ± 14 minutes for open pyeloplasty (n = 48) and 96 ± 18 minutes for laparoscopic pyeloplasty (n = 14) (p = 0.03). The estimated blood loss was insignificant in all cases (< 10 mL). One mucosal laceration due to ureteric spatulation healed successfully without sequelae. No conversions to open surgery were needed. Postoperative Safety Profile Postoperative complications were seen in 7 infants (11.3%), most of which were graded as Clavien–Dindo I or II. The most common complication was urinary tract infection, seen in 4 infants (6.5%). One infant had an anastomotic leak necessitating stent reinsertion (Clavien IIIb). The average hospital stay was 4.5 ± 1.2 days (open: 4.7, laparoscopic: 3.8; p = 0.01). ICU admission was not required. Table 2 shows postoperative complications graded according to Clavien–Dindo. The total complication rate was 11.3%. The most common was urinary tract infection (6.5%), followed by stent-related symptoms and wound infection (1.6% each). Anastomotic leak necessitating treatment occurred in one infant (1.6%). Most complications were minor and reflected a good postoperative safety profile. Table 2 Postoperative complications (Clavien–Dindo classification, n = 62) Complication type Number (%) Grade Urinary tract infection 4 (6.5%) II Anastomotic leak 1 (1.6%) IIIb Stent-related irritative symptoms 1 (1.6%) I Wound infection 1 (1.6%) II Total complications 7 (11.3%) — Efficacy Outcomes As of the 6-month follow-up, ultrasonography showed improvement in hydronephrosis in 55 infants (88.7%). At 12 months, diuretic renography revealed better drainage in 57 infants (91.9%), with the mean DRF from 32.5 ± 6.8% to 39.1 ± 7.2% (p < 0.001). Total surgical success, being symptomatic relief with better or same renal function and free drainage, was obtained in 59 infants (95.2%). Secondary intervention for recurrent obstruction was needed only in 3 infants (4.8%). Figure 1 demonstrates the enhancement in differential renal function after pyeloplasty in neonates and infants less than 1 year. Mean DRF rose from 32.5% preoperatively to 37.4% at 6 months and 39.1% at 12 months. The rising trend reflects considerable functional recovery, validating the efficacy and durability of early surgical correction. Subgroup Analyses Stratified by age, infants operated at less than 6 months (n = 28) had similar complication rates to infants operated from 6–12 months (n = 34) (10.7% vs 11.7%, p = 0.88). Change in DRF was greater in the early group (mean improvement: +7.1% vs + 4.2%, p = 0.02). Comparison of surgical approach gave success rates of 95.8% for the open group and 92.9% for the laparoscopic group (p = 0.61). Laparoscopic surgery took longer in the operating room but less time in the hospital (3.8 vs 4.7 days, p = 0.01). Table 3 contrasts outcomes between infants treated before and after 6 months. The complication rate was the same (10.7% vs 11.7%). DRF gain was significantly higher among younger patients (+ 7.1% vs + 4.2%, p = 0.02). Success rates were high and similar (96.4% vs 94.1%), reinforcing uniform efficacy. Table 3 Subgroup comparison of outcomes Variable < 6 months (n = 28) 6–12 months (n = 34) p-value Complication rate (%) 3 (10.7%) 4 (11.7%) 0.88 Mean DRF improvement (%) + 7.1 ± 2.5 + 4.2 ± 2.1 0.02 Success rate (%) 27 (96.4%) 32 (94.1%) 0.68 Statistical Significance General improvement in DRF was statistically significant (p < 0.001). Kaplan–Meier analysis revealed intervention-free survival at 1 and 3 years to be 98% and 95%, respectively. Preoperative DRF < 30% was found to be an independent predictor of suboptimal recovery (OR 2.4; 95% CI 1.1–5.1; p = 0.04). Figure 2 illustrates the Kaplan–Meier survival analysis for intervention-free outcomes following pyeloplasty in infants under the age of one year. One-year survival was 98% and three-year survival was 95% with only minimal re-intervention needed. The curve illustrates excellent long-term durability of surgical repair with its maintained effectiveness in early infancy. Discussion This research showed that pyeloplasty done on infants below the age of one year is safe and effective, and the perioperative complication rates are similar to those reported in older children, and the success rates are high. Of a total number of 62 infants, the rate of complication was 11.3, and most of them were minor complications that are classified under Clavien-Dindo I and II. A single infant (1.6) had an anastomotic leak that necessitated re-intervention, which supports the fact of low risk of serious adverse outcomes. There were positive functional results, and the mean of the difference renal function (DRF) increased significantly between 32.5% before operation and 39.1% at 12 months (p < 0.001). The success rates were above 95% and the Kaplan-Meier analysis revealed an intervention-free survival of 98% at 1 year and 95% at 3 years. Subgroup analysis showed that infants who underwent their pyeloplasty below the age of 6 months had better renal functional increase (7.1 vs 4.2, p = 0.02) without an increase in the rate of complications. Combined with the previous evidence, the findings herein suggest the notion that early surgical repair of UPJO can not only stop hydronephrosis development but also yield significant functional recovery to a small number of infants. Notably, there were no extra risks related to anesthetic complications, technical difficulties, or a long stay in the hospital with early pyeloplasty. The findings are consistent with a number of earlier published articles that have reported the safety of infant pyeloplasty. In the study by Salih et al., the complication rates were 8–12 percent in a large cohort of pediatric pyeloplasty, and there was no significant difference between infants and older children [ 15 ]. On the same note, Passoni et al. reported that robotic-assisted pyeloplasty in infants had the same outcome as open methods and a good safety profile [ 6 ]. These observations are supported by the findings, and the overall complication rates were within the expected range, and most of the complications were minor and self-limiting (e.g., urinary tract infection). Concerning efficacy, several studies have described a stable or even improved renal functioning after infancy pyeloplasty. In a 15-year follow-up series, Cerveira et al. reported that most children had a long-term maintenance of renal function following pyeloplasty irrespective of their age at the time of surgery [ 16 ]. Even more recent analyses, though, indicate that there is added value in terms of earlier intervention. Bansal et al. discovered that infants who received pyeloplasty before 6 months had the same safety rates but exhibited more DRF recovery than older children [ 17 ]. The research has evidence to this effect, as younger infants have shown more improvements in renal functioning. This is biologically feasible considering the fact that nephron maturation is fast during the first year of life, and functional parenchyma preservation is paramount at this stage [ 18 ]. The study also shows that the surgical outcomes are durable, which is similar to the literature. Kaplan-Meier showed long-term success at 3 years, which is comparable to long-term follow-up studies that show success rates of 90–98 percent over 10 years [ 19 ]. Other scientists have been worried about the occurrence of restenosis following early repair, but the data indicate that this is not a significant issue, as long as care is taken in the surgical process. However, it is also controversial in the literature whether to intervene at what time. Mild-to-moderate hydronephrosis has long been proposed to be treated with conservative management approaches to permit spontaneous resolution and prevent unwarranted surgery [ 20 ]. Owsiak has shown that half of the cases of neonatal hydronephrosis resolve spontaneously [ 21 ]. Nonetheless, these results might not apply to extreme hydronephrosis or drainage failure, where time delay in the intervention results in irreversible loss of nephrons. The scientists particularly targeted infants with severe or progressive obstruction, and the benefits observed underscore the need to correct these patients surgically. One of the strengths of this study is that it addresses the infant population, which is usually underrepresented in previous literature, and the infants used in the research are below the age of one year. Cohorts published mostly combine infants with other children, which makes it difficult to make age-specific conclusions. The confinement to this population gives us a strong piece of evidence that can be used in clinical decision-making when it comes to early pyeloplasty. The standardized approach, such as standard diagnostic procedures (SFU grading, diuretic renography), uniform surgical procedure (Anderson-Hynes dismembered pyeloplasty), and standardized follow-up, is another strength. This minimizes heterogeneity and enhances the faithfulness of the results. A combination of both functional (DRF improvement) and anatomical (hydronephrosis reduction) endpoints gives a detailed assessment of efficacy. The sample size of the infant group (n = 62) is also rather large in comparison to other previous single-centre reports that often involved less than 30 infants [ 22 ]. Also, statistical rigor is further provided by Kaplan-Meier survival analysis, which considers the time-varying events like re-intervention. The findings of this research have a number of clinical implications. To begin with, they offer the comfort that pyeloplasty in children at the age of less than one year is a safe operation, and complication rates are equal to those of older children. This would reduce the fears of the surgeons and anesthetists about the technical and perioperative risks of early intervention. Second, functionality recovery in younger infants encourages a more aggressive surgical intervention in severe obstruction. Instead of waiting with optimism that spontaneous improvement would occur and avoid surgery, clinicians can reflect on earlier intervention and renal preservation maximization. This becomes particularly applicable in the environment where the reliability of the follow-up is difficult, and the delays may translate into the loss of salvage opportunities. Third, shared decision-making with parents may be guided by the findings. Families receive conflicting advice on when to conduct pyeloplasty. The data provided in the present, which demonstrates both safety and efficacy, may be utilized to advise parents that early surgery is not only possible but also beneficial in the prevention of long-term renal compromise. From a health systems point of view, early definitive surgery could also lower the burden of long-term surveillance with serial imaging, which is financially costly, exposes patients to radiation, and causes psychological trauma to the families [ 23 ]. Therefore, besides clinical advantage, early pyeloplasty can have broader socioeconomic benefits. Limitations There are various limitations of this study. It was done in one centre, which limited its extrapolation to other populations and surgical environments. Even though the data were gathered prospectively, some of the outcomes were not measured, including anesthetic safety and parental satisfaction. The 3-year follow-up, although sufficient in the early failure, could be underestimating late complications such as recurrent obstruction at puberty; a 3-year follow-up to adolescence would be best. Infants who had bilateral UPJO and solitary kidneys were excluded, and the applicability was limited to otherwise healthy unilateral cases. Furthermore, the small laparoscopic subgroup (n = 14) restricts comparison with open surgery to be reliable. More multicenter trials or randomized studies are needed in order to prove durability and provide equivalence of surgical methods in very young infants. Future Directions Further studies are required to involve multiple centers and bigger infant cohorts to enhance evidence and make inferences, preferably based on standardized definitions of success, standardized imaging modalities, and extended follow-up until adolescence. The application of minimally invasive surgery in infants less than one year old also needs to be tested, since laparoscopic and robotic techniques, which have been proven effective in children older than one year, are technically challenging in infants younger than one year. There is a need for comparative studies to determine the long-term outcomes, cost-effectiveness, and parental satisfaction of open and minimally invasive methods. Determination of biomarkers or predictive models can further categorize infants at the highest risk of benefiting from early surgery, whereas qualitative studies on parental views and quality of life would be used to complement clinical evidence, as well as inform future management treatment. Conclusion The results of this research prove that in infants under the age of one year, pyeloplasty is a safe and effective procedure with a low level of complications and a high functional success. The morbidity of the surgical process was reduced, and the majority of the negative events were minor and treated in a non-acute manner. There was only one infant with an anastomotic leak, which needed re-intervention, indicating how rare severe complications are. There was also a significant improvement in functional outcomes, as differential renal function increased by 32.5% to 39.1% in 1 year, indicating improved obstruction relief and maintenance of renal parenchyma. At three years, intervention-free survival was more than 95 percent, which highlights the permanence of early repair. This subgroup analysis demonstrated that infants who underwent the operation before six months did better in improving renal functioning without the risk of a higher rate, and this highlights the possible advantages of early intervention during a critical phase of nephron development. These findings cover the current issue of anesthetic safety and technical difficulties in early infancy and indicate that these risks are reduced by the development of perioperative care and precision in surgery. Clinically, the data can be used to consider early pyeloplasty when faced with severe obstruction to prevent the risk of irreversible renal damage and decrease the cost of long-term surveillance. The expansion of the use of early surgical intervention can potentially enhance renal outcomes, maximise the quality of life, and lower the use of healthcare resources. These findings should be supported by multicenter studies with more extended follow-up to confirm their validity and improve the recommendations on how to manage UPJO in this high-risk group. Declarations Funding Declaration There were no external sources of funding for this study, hence, none received. Author Contribution All authors have equal contribution.All authors reviewed the final manuscript and approved for publication. Data Availability Data is provided within the manuscript. References Onen A. Grading of hydronephrosis: an ongoing challenge. Front Pediatr. 2020;8:458. Pakkasjärvi N, Belov S, Jahnukainen T, Kivisaari R, Taskinen S. Stratifying antenatal hydronephrosis: predicting high-grade VUR using ultrasound and scintigraphy. Diagnostics. 2024;14(4):384. Babu R, Suryawanshi AR, Shah US, Unny AK. Postnatal management of bilateral Grade 3–4 ureteropelvic junction obstruction. Indian Journal of Urology. 2020;36(4):288–94. ElSheemy MS. 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The Journal of Urology. 2021;206(4):1022–30. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 10 Nov, 2025 Read the published version in Egyptian Pediatric Association Gazette → Version 1 posted Editorial decision: Revision requested 15 Oct, 2025 Reviews received at journal 14 Oct, 2025 Reviews received at journal 07 Oct, 2025 Reviewers agreed at journal 30 Sep, 2025 Reviews received at journal 28 Sep, 2025 Reviewers agreed at journal 28 Sep, 2025 Reviewers agreed at journal 28 Sep, 2025 Reviewers agreed at journal 25 Sep, 2025 Reviewers invited by journal 23 Sep, 2025 Editor assigned by journal 23 Sep, 2025 Submission checks completed at journal 23 Sep, 2025 First submitted to journal 22 Sep, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7673320","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":524279244,"identity":"0be53211-6e85-49f7-8148-4119c035d2cd","order_by":0,"name":"Fayaz Ahmad 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Soura","correspondingAuthor":false,"prefix":"","firstName":"Altaf","middleName":"Ahmad","lastName":"Ganayee","suffix":""},{"id":524279246,"identity":"1d919436-d4e0-4ba5-9dee-ed41b3042ccc","order_by":2,"name":"Ubayer Nabi","email":"","orcid":"","institution":"SKIMS, Soura","correspondingAuthor":false,"prefix":"","firstName":"Ubayer","middleName":"","lastName":"Nabi","suffix":""},{"id":524279247,"identity":"e937705f-ecf2-4ff8-86c4-64d46582003a","order_by":3,"name":"Gowhar Nazir Mufti","email":"","orcid":"","institution":"SKIMS, Soura","correspondingAuthor":false,"prefix":"","firstName":"Gowhar","middleName":"Nazir","lastName":"Mufti","suffix":""},{"id":524279248,"identity":"a0458e8a-2af3-4b05-924d-9d7135a662bb","order_by":4,"name":"Aejaz Ahsan Baba","email":"","orcid":"","institution":"SKIMS, Soura","correspondingAuthor":false,"prefix":"","firstName":"Aejaz","middleName":"Ahsan","lastName":"Baba","suffix":""}],"badges":[],"createdAt":"2025-09-22 11:38:13","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7673320/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7673320/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s43054-025-00473-5","type":"published","date":"2025-11-10T15:58:17+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":92872809,"identity":"768efda7-d967-4bf6-8fee-fae055c10d3f","added_by":"auto","created_at":"2025-10-06 14:20:04","extension":"docx","order_by":0,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":117827,"visible":true,"origin":"","legend":"","description":"","filename":"pyeloplasty1yearmain.docx","url":"https://assets-eu.researchsquare.com/files/rs-7673320/v1/bd2508b1f052b693e21dff04.docx"},{"id":92872810,"identity":"1bd46880-cc04-44d8-b88a-006163e6d51c","added_by":"auto","created_at":"2025-10-06 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14:20:04","extension":"html","order_by":7,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":73752,"visible":true,"origin":"","legend":"","description":"","filename":"earlyproof.html","url":"https://assets-eu.researchsquare.com/files/rs-7673320/v1/396197e3e2fface78b59d092.html"},{"id":92872808,"identity":"7155dc76-d2dd-423a-b891-c02f8c6f71a1","added_by":"auto","created_at":"2025-10-06 14:20:04","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":21667,"visible":true,"origin":"","legend":"\u003cp\u003eMean differential renal function (DRF) over time\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-7673320/v1/5191d06e0dfe3c30ceb5772a.png"},{"id":92874569,"identity":"2840b2ac-7f81-4afd-b4c1-37dc8683ac3c","added_by":"auto","created_at":"2025-10-06 14:28:04","extension":"jpeg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":177432,"visible":true,"origin":"","legend":"\u003cp\u003eKaplan–Meier curve showing intervention-free survival following pyeloplasty in infants under 1 year\u003c/p\u003e","description":"","filename":"floatimage1.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7673320/v1/c42a766322d09a5e71c30630.jpeg"},{"id":96105241,"identity":"210fabfa-7afa-43d9-bc53-1e0ff8cf1e2a","added_by":"auto","created_at":"2025-11-17 16:10:23","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":854143,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7673320/v1/b7cc05c3-bb1c-441a-af82-89fa3cf50250.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Safety and Efficacy of Pyeloplasty in Children aged less than 1 year: Experience from a Tertiary Care Hospital of North India","fulltext":[{"header":"Introduction","content":"\u003cp\u003eUreteropelvic junction obstruction (UPJO) is the most prevalent etiology of hydronephrosis in children and is responsible for almost 35\u0026ndash;45% of prenatally diagnosed urinary tract anomalies [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. Improvement in antenatal ultrasonography has resulted in increased detection of hydronephrosis, with many such cases later confirmed as UPJO in the neonatal or early infant stage [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Even though some instances of hydronephrosis are spontaneously resolving and self-limiting, persistent or severe obstruction carries considerable risks of progressive renal injury, recurrent UTIs, and compromised renal growth [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Therefore, treatment of UPJO in early life has remained a longstanding area of interest in clinical and academic practice in pediatric urology.\u003c/p\u003e\u003cp\u003eThe optimal timing of surgical repair, especially pyeloplasty, in infants under one year of age continues to be a matter of significant controversy. Clinicians traditionally waited until after the first year of life because of concerns for anesthetic safety, technical difficulties in the tiny infant, and the possibility of spontaneous resolution [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Yet, mounting evidence has proved that delayed intervention can allow for irreversible renal parenchymal damage, particularly in severe obstruction [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. On the other hand, early infant pyeloplasty has the theoretical advantage of maintaining renal function during a phase of accelerated nephrogenesis and renal maturation [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. This balance between these two opposing risks supports clinical controversy.\u003c/p\u003e\u003cp\u003eSeveral retrospective and prospective investigations have tried to address the safety and efficacy of pyeloplasty early on. Complication rates involving anastomotic leak, urinary tract infection, or restenosis have been reported to be similar for infants operated on before and after 12 months of age, according to some reports [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. In addition, advances in anesthetic monitoring, neonatal intensive care, and surgery, such as the availability of smaller instruments and magnification, have optimized the safety profile of early surgery [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. However, heterogeneity of study populations, surgical technique (open vs minimally invasive), and follow-up strategies reduces the external validity of these data [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. Another question that has not been answered is the long-term functional results of early pyeloplasty. Whereas some scientists have described dramatic improvement in differential renal function (DRF) after operation in infants [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e], others have mentioned stabilization and not dramatic improvement, especially when the initial function was already significantly compromised [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. The heterogeneity of renal recovery highlights the need for the determination of prognostic factors that can identify which infants are likely to gain the most from early treatment. In addition, although functional imaging tests like diuretic renography are very useful, they are probably less accurate in extremely young babies, making clinical decision-making more challenging [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eThere is still limited high-quality, sufficiently powered research exclusively in infants under one year of age. Most of the existing data derive from mixed-age series where infants are only a subset. Accordingly, there is minimal evidence of whether pyeloplasty done in the first year of life has any special risks or advantages over later intervention [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. In addition, most previous studies focus on perioperative safety or radiological results, but not on both in an inclusive way. Such compartmentalization creates an important knowledge deficit on the entire safety-efficacy balance of pyeloplasty in this population. Clinically, the choice to move forward with early pyeloplasty needs to be weighed carefully in terms of parental distress, consumption of healthcare resources, and ultimate prognosis. Parents of infants with severe hydronephrosis are frequently faced with conflicting advice, which contributes to decisional distress [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. Additionally, healthcare systems need to balance the expense of serial imaging and extended surveillance against the advantages of definitive early intervention. Accordingly, evidence-based advice is crucial to counsel both families and clinicians.\u003c/p\u003e\n\u003ch3\u003eObjectives\u003c/h3\u003e\n\u003cp\u003eThe aim of this research was to systematically analyze the efficacy and safety of pyeloplasty in children younger than one year of age. It attempted to study perioperative results, such as hospitalization and complication rates, along with functional efficacy by radiological as well as clinical parameters.\u003c/p\u003e\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\u003cdiv id=\"Sec4\" class=\"Section3\"\u003e\u003c/div\u003e\u003c/div\u003e"},{"header":"Methods","content":"\u003ch2\u003eStudy Design\u003c/h2\u003e\u003cp\u003eThis was a prospective cohort study from one of the tertiary care pediatric surgery centers of North India. All consecutive infants younger than 12 months who were operated on with pyeloplasty for ureteropelvic junction obstruction (UPJO) were included. The design permitted systematic perioperative data collection, standardized postoperative follow-up, and objective evaluation of both safety and efficacy outcomes.\u003c/p\u003e\n\u003ch3\u003eHuman Ethics and Consent to Participate\u003c/h3\u003e\n\u003cp\u003eThe study was performed according to the Declaration of Helsinki. Approval was received from the Institutional Ethics Committee (\u003cb\u003eIEC-SKIMS/2022\u003c/b\u003e) before the start of the study.\u003c/p\u003e\u003cp\u003eWritten informed consent was obtained from the parents and/or legal guardians of all infants before enrollment and surgery.\u003c/p\u003e\n\u003ch3\u003eInclusion Criteria\u003c/h3\u003e\n\u003cp\u003eThe inclusion criteria were all infants under 12 months of age at surgery, those with radiologically confirmed hydronephrosis having an anteroposterior renal pelvic diameter of \u0026gt;\u0026thinsp;20 mm or progressive dilatation on follow-up ultrasonography, and those with obstructed drainage or differential renal function of \u0026lt;\u0026thinsp;40% on diuretic renography.\u003c/p\u003e\n\u003ch3\u003eExclusion Criteria\u003c/h3\u003e\n\u003cp\u003eExclusion criteria were infants with bilateral ureteropelvic junction obstruction that needed surgery at the same time, known associated major urological abnormalities such as posterior urethral valves or vesicoureteral reflux, solitary functioning kidney infants, and those with suboptimal or incomplete follow-up information.\u003c/p\u003e\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\u003ch2\u003eDiagnostic Evaluation\u003c/h2\u003e\u003cp\u003eA uniform diagnostic protocol was used in all patients before surgery. Initial assessment consisted of a renal and bladder ultrasound to determine the grade of hydronephrosis based on the Society for Fetal Urology (SFU) classification. Diuretic renography with technetium-99m mercaptoacetyltriglycine (99mTc-MAG3) was done to establish obstruction and measure differential renal function (DRF). In selected cases, magnetic resonance urography was used to offer anatomical information and rule out crossing vessels. Laboratory tests consisted of serum creatinine and urinalysis to detect preoperative infection.\u003c/p\u003e\u003c/div\u003e\n\u003ch3\u003eSurgical Technique\u003c/h3\u003e\n\u003cp\u003eAll of the pyeloplasties were done under general anesthesia with endotracheal intubation. The surgical technique was at the surgeon's discretion and the infant's anatomy. Open pyeloplasty through a short flank incision was routine, and laparoscopic dismembered pyeloplasty was provided for selected infants weighing\u0026thinsp;\u0026gt;\u0026thinsp;5 kg. In both methods, the Anderson\u0026ndash;Hynes dismembered pyeloplasty was carried out, with careful spatulation of the ureter and watertight anastomosis with fine absorbable sutures. At the discretion of the surgeon, a trans anastomotic stent or external nephrostomy tube was left in place. Perioperative antibiotic prophylaxis was given by institutional policy.\u003c/p\u003e\n\u003ch3\u003eOutcome Measures\u003c/h3\u003e\n\u003cp\u003eThe main outcomes were obstruction as evidenced by augmented drainage pattern on diuretic postoperative renography, and recovery function as stabilization or improvement of differential renal function. The secondary outcomes comprised intraoperative factors like time of operation, blood loss, and intraoperative complications, and postoperative outcomes such as complication rates scored using Clavien\u0026ndash;Dindo classification, hospital stay, readmission, re-intervention, and general rate of success.\u003c/p\u003e\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e\u003ch2\u003eFollow-Up Protocol\u003c/h2\u003e\u003cp\u003ePatients were examined at 1 month, 3 months, 6 months, and then once a year for a maximum of 3 years. At each visit, clinical assessment and ultrasonography were conducted to evaluate hydronephrosis. Diuretic renography was performed at 6 months and 12 months after surgery, or sooner if there was a symptom or imaging evidence of obstruction. Renal function and status regarding complications were recorded at each interval.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e\u003ch2\u003eStatistical Analysis\u003c/h2\u003e\u003cp\u003eAll information was entered into a prospectively kept database. Continuous variables were presented as mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD or median with IQR as relevant. Categorical variables were described in frequencies and percentages. The paired t-test or Wilcoxon signed-rank test was employed to compare preoperative with postoperative renal function. The Kaplan\u0026ndash;Meier survival estimate was utilized to calculate intervention-free survival. Logistic regression analysis was used to determine predictors of surgical success and complications. Statistical significance was defined as a p-value\u0026thinsp;\u0026lt;\u0026thinsp;0.05. Statistical analysis was conducted with SPSS version 22.\u003c/p\u003e\u003c/div\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec14\" class=\"Section2\"\u003e\u003ch2\u003eBaseline Characteristics\u003c/h2\u003e\u003cp\u003eA total of 62 infants (male: 38, female: 24) underwent pyeloplasty during the study period. The mean age at surgery was 6.2\u0026thinsp;\u0026plusmn;\u0026thinsp;2.8 months (range: 2\u0026ndash;11 months). The left kidney was affected in 37 cases (59.7%), the right kidney in 25 cases (40.3%), and bilateral obstruction requiring staged intervention in 3 cases (4.8%). Preoperative imaging detected gross hydronephrosis (SFU grade 3\u0026ndash;4) in 54 infants (87.1%), with an anteroposterior pelvic diameter of 28.6\u0026thinsp;\u0026plusmn;\u0026thinsp;6.1 mm. The preoperative differential renal function averaged 32.5\u0026thinsp;\u0026plusmn;\u0026thinsp;6.8%. Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e outlines the 62 infants treated with pyeloplasty and their baseline characteristics. The average age was 6.2 months, with a male-to-female ratio of 38:24. Obstruction was more frequently left-sided than right-sided. The majority of babies had severe hydronephrosis (87.1%), with an average anteroposterior diameter of 28.6 mm and an average preoperative DRF of 32.5%.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eBaseline demographic and clinical characteristics of infants (n\u0026thinsp;=\u0026thinsp;62)\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"2\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eVariable\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eValue\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMean age at surgery (months)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e6.2\u0026thinsp;\u0026plusmn;\u0026thinsp;2.8 (range: 2\u0026ndash;11)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGender (Male: Female)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e38:24\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eLaterality (Left: Right)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e37:25\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBilateral obstruction (staged)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e3 (4.8%)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSevere hydronephrosis (SFU 3\u0026ndash;4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e54 (87.1%)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMean AP diameter (mm)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e28.6\u0026thinsp;\u0026plusmn;\u0026thinsp;6.1\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMean preoperative DRF (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e32.5\u0026thinsp;\u0026plusmn;\u0026thinsp;6.8\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec15\" class=\"Section2\"\u003e\u003ch2\u003eIntraoperative Outcomes\u003c/h2\u003e\u003cp\u003eThe median operative time was 76\u0026thinsp;\u0026plusmn;\u0026thinsp;14 minutes for open pyeloplasty (n\u0026thinsp;=\u0026thinsp;48) and 96\u0026thinsp;\u0026plusmn;\u0026thinsp;18 minutes for laparoscopic pyeloplasty (n\u0026thinsp;=\u0026thinsp;14) (p\u0026thinsp;=\u0026thinsp;0.03). The estimated blood loss was insignificant in all cases (\u0026lt;\u0026thinsp;10 mL). One mucosal laceration due to ureteric spatulation healed successfully without sequelae. No conversions to open surgery were needed.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec16\" class=\"Section2\"\u003e\u003ch2\u003ePostoperative Safety Profile\u003c/h2\u003e\u003cp\u003ePostoperative complications were seen in 7 infants (11.3%), most of which were graded as Clavien\u0026ndash;Dindo I or II. The most common complication was urinary tract infection, seen in 4 infants (6.5%). One infant had an anastomotic leak necessitating stent reinsertion (Clavien IIIb). The average hospital stay was 4.5\u0026thinsp;\u0026plusmn;\u0026thinsp;1.2 days (open: 4.7, laparoscopic: 3.8; p\u0026thinsp;=\u0026thinsp;0.01). ICU admission was not required. Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e shows postoperative complications graded according to Clavien\u0026ndash;Dindo. The total complication rate was 11.3%. The most common was urinary tract infection (6.5%), followed by stent-related symptoms and wound infection (1.6% each). Anastomotic leak necessitating treatment occurred in one infant (1.6%). Most complications were minor and reflected a good postoperative safety profile.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003ePostoperative complications (Clavien\u0026ndash;Dindo classification, n\u0026thinsp;=\u0026thinsp;62)\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"3\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eComplication type\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eNumber (%)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eGrade\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eUrinary tract infection\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e4 (6.5%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eII\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAnastomotic leak\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e1 (1.6%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eIIIb\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eStent-related irritative symptoms\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e1 (1.6%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eI\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eWound infection\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e1 (1.6%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eII\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eTotal complications\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e7 (11.3%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u0026mdash;\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec17\" class=\"Section2\"\u003e\u003ch2\u003eEfficacy Outcomes\u003c/h2\u003e\u003cp\u003eAs of the 6-month follow-up, ultrasonography showed improvement in hydronephrosis in 55 infants (88.7%). At 12 months, diuretic renography revealed better drainage in 57 infants (91.9%), with the mean DRF from 32.5\u0026thinsp;\u0026plusmn;\u0026thinsp;6.8% to 39.1\u0026thinsp;\u0026plusmn;\u0026thinsp;7.2% (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). Total surgical success, being symptomatic relief with better or same renal function and free drainage, was obtained in 59 infants (95.2%). Secondary intervention for recurrent obstruction was needed only in 3 infants (4.8%). Figure\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e demonstrates the enhancement in differential renal function after pyeloplasty in neonates and infants less than 1 year. Mean DRF rose from 32.5% preoperatively to 37.4% at 6 months and 39.1% at 12 months. The rising trend reflects considerable functional recovery, validating the efficacy and durability of early surgical correction.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec18\" class=\"Section2\"\u003e\u003ch2\u003eSubgroup Analyses\u003c/h2\u003e\u003cp\u003eStratified by age, infants operated at less than 6 months (n\u0026thinsp;=\u0026thinsp;28) had similar complication rates to infants operated from 6\u0026ndash;12 months (n\u0026thinsp;=\u0026thinsp;34) (10.7% vs 11.7%, p\u0026thinsp;=\u0026thinsp;0.88). Change in DRF was greater in the early group (mean improvement: +7.1% vs\u0026thinsp;+\u0026thinsp;4.2%, p\u0026thinsp;=\u0026thinsp;0.02). Comparison of surgical approach gave success rates of 95.8% for the open group and 92.9% for the laparoscopic group (p\u0026thinsp;=\u0026thinsp;0.61). Laparoscopic surgery took longer in the operating room but less time in the hospital (3.8 vs 4.7 days, p\u0026thinsp;=\u0026thinsp;0.01). Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e contrasts outcomes between infants treated before and after 6 months. The complication rate was the same (10.7% vs 11.7%). DRF gain was significantly higher among younger patients (+\u0026thinsp;7.1% vs\u0026thinsp;+\u0026thinsp;4.2%, p\u0026thinsp;=\u0026thinsp;0.02). Success rates were high and similar (96.4% vs 94.1%), reinforcing uniform efficacy.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eSubgroup comparison of outcomes\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"4\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eVariable\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;6 months (n\u0026thinsp;=\u0026thinsp;28)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003e6\u0026ndash;12 months (n\u0026thinsp;=\u0026thinsp;34)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003ep-value\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eComplication rate (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e3 (10.7%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e4 (11.7%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.88\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMean DRF improvement (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e+\u0026thinsp;7.1\u0026thinsp;\u0026plusmn;\u0026thinsp;2.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e+\u0026thinsp;4.2\u0026thinsp;\u0026plusmn;\u0026thinsp;2.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.02\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSuccess rate (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e27 (96.4%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e32 (94.1%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.68\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec19\" class=\"Section2\"\u003e\u003ch2\u003eStatistical Significance\u003c/h2\u003e\u003cp\u003eGeneral improvement in DRF was statistically significant (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). Kaplan\u0026ndash;Meier analysis revealed intervention-free survival at 1 and 3 years to be 98% and 95%, respectively. Preoperative DRF\u0026thinsp;\u0026lt;\u0026thinsp;30% was found to be an independent predictor of suboptimal recovery (OR 2.4; 95% CI 1.1\u0026ndash;5.1; p\u0026thinsp;=\u0026thinsp;0.04). Figure\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e illustrates the Kaplan\u0026ndash;Meier survival analysis for intervention-free outcomes following pyeloplasty in infants under the age of one year. One-year survival was 98% and three-year survival was 95% with only minimal re-intervention needed. The curve illustrates excellent long-term durability of surgical repair with its maintained effectiveness in early infancy.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis research showed that pyeloplasty done on infants below the age of one year is safe and effective, and the perioperative complication rates are similar to those reported in older children, and the success rates are high. Of a total number of 62 infants, the rate of complication was 11.3, and most of them were minor complications that are classified under Clavien-Dindo I and II. A single infant (1.6) had an anastomotic leak that necessitated re-intervention, which supports the fact of low risk of serious adverse outcomes. There were positive functional results, and the mean of the difference renal function (DRF) increased significantly between 32.5% before operation and 39.1% at 12 months (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). The success rates were above 95% and the Kaplan-Meier analysis revealed an intervention-free survival of 98% at 1 year and 95% at 3 years. Subgroup analysis showed that infants who underwent their pyeloplasty below the age of 6 months had better renal functional increase (7.1 vs 4.2, p\u0026thinsp;=\u0026thinsp;0.02) without an increase in the rate of complications. Combined with the previous evidence, the findings herein suggest the notion that early surgical repair of UPJO can not only stop hydronephrosis development but also yield significant functional recovery to a small number of infants. Notably, there were no extra risks related to anesthetic complications, technical difficulties, or a long stay in the hospital with early pyeloplasty.\u003c/p\u003e\u003cp\u003eThe findings are consistent with a number of earlier published articles that have reported the safety of infant pyeloplasty. In the study by Salih et al., the complication rates were 8\u0026ndash;12 percent in a large cohort of pediatric pyeloplasty, and there was no significant difference between infants and older children [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. On the same note, Passoni et al. reported that robotic-assisted pyeloplasty in infants had the same outcome as open methods and a good safety profile [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. These observations are supported by the findings, and the overall complication rates were within the expected range, and most of the complications were minor and self-limiting (e.g., urinary tract infection). Concerning efficacy, several studies have described a stable or even improved renal functioning after infancy pyeloplasty. In a 15-year follow-up series, Cerveira et al. reported that most children had a long-term maintenance of renal function following pyeloplasty irrespective of their age at the time of surgery [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. Even more recent analyses, though, indicate that there is added value in terms of earlier intervention. Bansal et al. discovered that infants who received pyeloplasty before 6 months had the same safety rates but exhibited more DRF recovery than older children [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. The research has evidence to this effect, as younger infants have shown more improvements in renal functioning. This is biologically feasible considering the fact that nephron maturation is fast during the first year of life, and functional parenchyma preservation is paramount at this stage [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. The study also shows that the surgical outcomes are durable, which is similar to the literature. Kaplan-Meier showed long-term success at 3 years, which is comparable to long-term follow-up studies that show success rates of 90\u0026ndash;98 percent over 10 years [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. Other scientists have been worried about the occurrence of restenosis following early repair, but the data indicate that this is not a significant issue, as long as care is taken in the surgical process. However, it is also controversial in the literature whether to intervene at what time. Mild-to-moderate hydronephrosis has long been proposed to be treated with conservative management approaches to permit spontaneous resolution and prevent unwarranted surgery [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. Owsiak has shown that half of the cases of neonatal hydronephrosis resolve spontaneously [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. Nonetheless, these results might not apply to extreme hydronephrosis or drainage failure, where time delay in the intervention results in irreversible loss of nephrons. The scientists particularly targeted infants with severe or progressive obstruction, and the benefits observed underscore the need to correct these patients surgically.\u003c/p\u003e\u003cp\u003eOne of the strengths of this study is that it addresses the infant population, which is usually underrepresented in previous literature, and the infants used in the research are below the age of one year. Cohorts published mostly combine infants with other children, which makes it difficult to make age-specific conclusions. The confinement to this population gives us a strong piece of evidence that can be used in clinical decision-making when it comes to early pyeloplasty. The standardized approach, such as standard diagnostic procedures (SFU grading, diuretic renography), uniform surgical procedure (Anderson-Hynes dismembered pyeloplasty), and standardized follow-up, is another strength. This minimizes heterogeneity and enhances the faithfulness of the results. A combination of both functional (DRF improvement) and anatomical (hydronephrosis reduction) endpoints gives a detailed assessment of efficacy. The sample size of the infant group (n\u0026thinsp;=\u0026thinsp;62) is also rather large in comparison to other previous single-centre reports that often involved less than 30 infants [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. Also, statistical rigor is further provided by Kaplan-Meier survival analysis, which considers the time-varying events like re-intervention.\u003c/p\u003e\u003cp\u003eThe findings of this research have a number of clinical implications. To begin with, they offer the comfort that pyeloplasty in children at the age of less than one year is a safe operation, and complication rates are equal to those of older children. This would reduce the fears of the surgeons and anesthetists about the technical and perioperative risks of early intervention. Second, functionality recovery in younger infants encourages a more aggressive surgical intervention in severe obstruction. Instead of waiting with optimism that spontaneous improvement would occur and avoid surgery, clinicians can reflect on earlier intervention and renal preservation maximization. This becomes particularly applicable in the environment where the reliability of the follow-up is difficult, and the delays may translate into the loss of salvage opportunities. Third, shared decision-making with parents may be guided by the findings. Families receive conflicting advice on when to conduct pyeloplasty. The data provided in the present, which demonstrates both safety and efficacy, may be utilized to advise parents that early surgery is not only possible but also beneficial in the prevention of long-term renal compromise. From a health systems point of view, early definitive surgery could also lower the burden of long-term surveillance with serial imaging, which is financially costly, exposes patients to radiation, and causes psychological trauma to the families [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. Therefore, besides clinical advantage, early pyeloplasty can have broader socioeconomic benefits.\u003c/p\u003e\u003cdiv id=\"Sec21\" class=\"Section2\"\u003e\u003ch2\u003eLimitations\u003c/h2\u003e\u003cp\u003eThere are various limitations of this study. It was done in one centre, which limited its extrapolation to other populations and surgical environments. Even though the data were gathered prospectively, some of the outcomes were not measured, including anesthetic safety and parental satisfaction. The 3-year follow-up, although sufficient in the early failure, could be underestimating late complications such as recurrent obstruction at puberty; a 3-year follow-up to adolescence would be best. Infants who had bilateral UPJO and solitary kidneys were excluded, and the applicability was limited to otherwise healthy unilateral cases. Furthermore, the small laparoscopic subgroup (n\u0026thinsp;=\u0026thinsp;14) restricts comparison with open surgery to be reliable. More multicenter trials or randomized studies are needed in order to prove durability and provide equivalence of surgical methods in very young infants.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec22\" class=\"Section2\"\u003e\u003ch2\u003eFuture Directions\u003c/h2\u003e\u003cp\u003eFurther studies are required to involve multiple centers and bigger infant cohorts to enhance evidence and make inferences, preferably based on standardized definitions of success, standardized imaging modalities, and extended follow-up until adolescence. The application of minimally invasive surgery in infants less than one year old also needs to be tested, since laparoscopic and robotic techniques, which have been proven effective in children older than one year, are technically challenging in infants younger than one year. There is a need for comparative studies to determine the long-term outcomes, cost-effectiveness, and parental satisfaction of open and minimally invasive methods. Determination of biomarkers or predictive models can further categorize infants at the highest risk of benefiting from early surgery, whereas qualitative studies on parental views and quality of life would be used to complement clinical evidence, as well as inform future management treatment.\u003c/p\u003e\u003c/div\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThe results of this research prove that in infants under the age of one year, pyeloplasty is a safe and effective procedure with a low level of complications and a high functional success. The morbidity of the surgical process was reduced, and the majority of the negative events were minor and treated in a non-acute manner. There was only one infant with an anastomotic leak, which needed re-intervention, indicating how rare severe complications are. There was also a significant improvement in functional outcomes, as differential renal function increased by 32.5% to 39.1% in 1 year, indicating improved obstruction relief and maintenance of renal parenchyma. At three years, intervention-free survival was more than 95 percent, which highlights the permanence of early repair. This subgroup analysis demonstrated that infants who underwent the operation before six months did better in improving renal functioning without the risk of a higher rate, and this highlights the possible advantages of early intervention during a critical phase of nephron development. These findings cover the current issue of anesthetic safety and technical difficulties in early infancy and indicate that these risks are reduced by the development of perioperative care and precision in surgery. Clinically, the data can be used to consider early pyeloplasty when faced with severe obstruction to prevent the risk of irreversible renal damage and decrease the cost of long-term surveillance. The expansion of the use of early surgical intervention can potentially enhance renal outcomes, maximise the quality of life, and lower the use of healthcare resources. These findings should be supported by multicenter studies with more extended follow-up to confirm their validity and improve the recommendations on how to manage UPJO in this high-risk group.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cb\u003eFunding Declaration\u003c/b\u003e\u003c/p\u003e\u003cp\u003eThere were no external sources of funding for this study, hence, none received.\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eAll authors have equal contribution.All authors reviewed the final manuscript and approved for publication.\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eData is provided within the manuscript.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eOnen A. Grading of hydronephrosis: an ongoing challenge. Front Pediatr. 2020;8:458.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003ePakkasj\u0026auml;rvi N, Belov S, Jahnukainen T, Kivisaari R, Taskinen S. Stratifying antenatal hydronephrosis: predicting high-grade VUR using ultrasound and scintigraphy. Diagnostics. 2024;14(4):384.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBabu R, Suryawanshi AR, Shah US, Unny AK. Postnatal management of bilateral Grade 3\u0026ndash;4 ureteropelvic junction obstruction. Indian Journal of Urology. 2020;36(4):288\u0026ndash;94.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eElSheemy MS. Postnatal management of children with antenatal hydronephrosis. African Journal of Urology. 2020;26(1):86.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBilge I. Symptomatology and clinic of hydronephrosis associated with uretero pelvic junction anomalies. Frontiers in Pediatrics. 2020;8:520.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003ePassoni NM, Peters CA. Managing ureteropelvic junction obstruction in the young infant. Frontiers in Pediatrics. 2020;8:242.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eHe Y, Song H, Liu P, Sun N, Tian J, Li M, Li N, Qu Y, Han W, Feng G, Ni X. Primary laparoscopic pyeloplasty in children: a single-center experience of 279 patients and analysis of possible factors affecting complications. Journal of Pediatric Urology. 2020;16(3):331-e1.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eChen J, Xu H, Lin S, He S, Tang K, Xiao Z, Xu D. Robot-assisted pyeloplasty and laparoscopic pyeloplasty in children: a comparison of single-port-plus-one and multiport surgery. Frontiers in Pediatrics. 2022;10:957790.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eV\u0026auml;rel\u0026auml; S, Omling E, B\u0026ouml;rjesson A, Sal\u0026ouml; M. Resolution of hydronephrosis after pyeloplasty in children. Journal of Pediatric Urology. 2021;17(1):102-e1.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eU\u0026ccedil;an AB, Yaslı G, Şahin M, Okur \u0026Ouml;, Şencan A. Long-Term Outcomes of Pyeloplasty in Children with Poorly Functioning Kidneys. Journal of Urological Surgery. 2023 Dec 15.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eGopal M, Peycelon M, Caldamone A, Chrzan R, El-Ghoneimi A, Olsen H, Leclair MD, Stillebroer A, MacDonald C, Tonnhofer U, Strasser C. Management of ureteropelvic junction obstruction in children\u0026mdash;a roundtable discussion. Journal of Pediatric Urology. 2019;15(4):322\u0026ndash;9.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBar-Sever Z, Shammas A, Gheisari F, Vali R. Pediatric nephro-urology: overview and updates in diuretic renal scans and renal cortical scintigraphy. InSeminars in nuclear medicine 2022 Jul 1 (Vol. 52, No. 4, pp. 419\u0026ndash;431). WB Saunders.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eOrtiz-Seller D, Panach-Navarrete J, Valls-Gonz\u0026aacute;lez L, Mart\u0026iacute;nez-Jabaloyas JM. Comparison between open and minimally invasive pyeloplasty in infants: A systematic review and meta-analysis. Journal of Pediatric Urology. 2024;20(2):244\u0026ndash;52.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eSepahi MA, Ahangary R, Ghaneaa A, Sadeghimogadam P, Heidari M. Outcome of isolated cases of antenatal hydronephrosis and its correlation with urinary tract anomalies. Journal of Renal Injury Prevention. 2017;7(3):160\u0026ndash;3.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eSalih E, Abdelmaksoud I, Elfeky M, Selmy G, Galal H, Zekry M. Renal functional improvement after pediatric pyeloplasty in kidneys with split renal function less than 20%: a single institute experience. Annals of Pediatric Surgery. 2021;17(1).\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eAlizadeh F, Haghdani S, Seydmohammadi B. Minimally invasive open pyeloplasty in children: Long-term follow-up. Turkish Journal of Urology. 2020;46(5):393.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eKafka IZ, Kocherov S, Jaber J, Chertin B. Pediatric robotic-assisted laparoscopic pyeloplasty (RALP): does weight matter?. Pediatric Surgery International. 2019;35(3):391\u0026ndash;6.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eCascini V, Lauriti G, Di Renzo D, Miscia ME, Lisi G. Ureteropelvic junction obstruction in infants: Open or minimally invasive surgery? A systematic review and meta-analysis. Frontiers in Pediatrics. 2022;10:1052440.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBergamo JA, Bayne CE. Featuring: management of ureteropelvic junction obstruction in children\u0026ndash;a roundtable discussion. Journal of pediatric urology. 2019;15(4):330\u0026ndash;1.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eSarhan OM, Helaly AE, Otay AA, Ghanbar MA, Nakshabandi Z. Isolated low grade prenatally detected unilateral hydronephrosis: do we need long term follow-up?. International braz j urol. 2018;44(4):812\u0026ndash;8.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eOwsiak M, Poncyljusz W, Safranow K. Diagnostic imaging in pediatric hydronephrosis. Pomeranian Journal of Life Sciences. 2022;68(1).\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMorales-L\u0026oacute;pez RA, P\u0026eacute;rez-March\u0026aacute;n M, P\u0026eacute;rez Brayfield M. Current concepts in pediatric robotic assisted pyeloplasty. Frontiers in pediatrics. 2019;7:4.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMelo FF, Mak RH, Sim\u0026otilde;es e Silva AC, Vasconcelos MA, Dias CS, Rosa LC, Shiomatsu GY, Storch C, Oliveira MC, Oliveira EA. Evaluation of urinary tract dilation classification system for prediction of long-term outcomes in isolated antenatal hydronephrosis: a cohort study. The Journal of Urology. 2021;206(4):1022\u0026ndash;30.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"egyptian-pediatric-association-gazette","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"epag","sideBox":"Learn more about [Egyptian Pediatric Association Gazette](https://epag.springeropen.com)","snPcode":"43054","submissionUrl":"https://submission.springernature.com/new-submission/43054/3?","title":"Egyptian Pediatric Association Gazette","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Pyeloplasty, infants, hydronephrosis, ureteropelvic junction obstruction, renal function","lastPublishedDoi":"10.21203/rs.3.rs-7673320/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7673320/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eIntroduction\u003c/h2\u003e\u003cp\u003eUreteropelvic junction obstruction (UPJO) is the predominant etiology of hydronephrosis in neonates and can lead to chronic renal impairment if not treated. The timing of pyeloplasty in infants under the age of one is controversial secondary to issues of anesthetic safety, technical complexity, and spontaneous resolution.\u003c/p\u003e\u003ch2\u003eMaterials and Methods\u003c/h2\u003e\u003cp\u003eThis prospective cohort study assessed the safety and effectiveness of pyeloplasty in 62 infants less than 12 months old. Inclusion criteria were obstructed hydronephrosis or compromised drainage, and exclusion criteria included bilateral UPJO requiring synchronous intervention, solitary kidney, or concomitant anomalies. Open or laparoscopic Anderson\u0026ndash;Hynes pyeloplasty was done, with follow-up standardized to include ultrasonography and diuretic renography.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e\u003cp\u003eMean age at surgery was 6.2\u0026thinsp;\u0026plusmn;\u0026thinsp;2.8 months. Postoperative complications in 11.3% of infants were primarily minor, with only one requiring re-intervention. Differential renal function also significantly improved from 32.5\u0026thinsp;\u0026plusmn;\u0026thinsp;6.8% preoperatively to 39.1\u0026thinsp;\u0026plusmn;\u0026thinsp;7.2% by 12 months (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). Success of the operation was seen in 95.2%, with Kaplan\u0026ndash;Meier survival at one year and three years at 98% and 95%, respectively, being intervention-free.\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e\u003cp\u003eEarly pyeloplasty is safe, effective, and with significant functional recovery, especially in infants operated on before the age of 6 months.\u003c/p\u003e","manuscriptTitle":"Safety and Efficacy of Pyeloplasty in Children aged less than 1 year: Experience from a Tertiary Care Hospital of North India","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-10-06 14:19:59","doi":"10.21203/rs.3.rs-7673320/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-10-15T04:30:55+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-10-15T02:59:21+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-10-07T15:31:11+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"262448687750390834758912902333246694367","date":"2025-09-30T04:02:13+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-09-29T01:52:55+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"181254776033004991052906002092420798800","date":"2025-09-29T00:44:30+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"203697862573023551008821785124700301604","date":"2025-09-28T15:48:42+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"321758661027665984595534254317252941473","date":"2025-09-25T13:58:33+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-09-23T12:51:28+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-09-23T12:41:49+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-09-23T12:40:29+00:00","index":"","fulltext":""},{"type":"submitted","content":"Egyptian Pediatric Association Gazette","date":"2025-09-22T09:38:52+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"egyptian-pediatric-association-gazette","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"epag","sideBox":"Learn more about [Egyptian Pediatric Association Gazette](https://epag.springeropen.com)","snPcode":"43054","submissionUrl":"https://submission.springernature.com/new-submission/43054/3?","title":"Egyptian Pediatric Association Gazette","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"96e6262d-7810-442f-b9d8-ff2765b8228f","owner":[],"postedDate":"October 6th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-11-17T16:06:02+00:00","versionOfRecord":{"articleIdentity":"rs-7673320","link":"https://doi.org/10.1186/s43054-025-00473-5","journal":{"identity":"egyptian-pediatric-association-gazette","isVorOnly":false,"title":"Egyptian Pediatric Association Gazette"},"publishedOn":"2025-11-10 15:58:17","publishedOnDateReadable":"November 10th, 2025"},"versionCreatedAt":"2025-10-06 14:19:59","video":"","vorDoi":"10.1186/s43054-025-00473-5","vorDoiUrl":"https://doi.org/10.1186/s43054-025-00473-5","workflowStages":[]},"version":"v1","identity":"rs-7673320","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7673320","identity":"rs-7673320","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}