Paediatric urolithiasis is no longer an uncommon condition. Its incidence has risen over recent decades, and the disease remains endemic across the Afro-Asian "stone belt", which includes Pakistan, where hot climate, dehydration, dietary factors and high consanguinity contribute to a heavy burden of renal stones in childhood.1 Stones in children carry particular concerns because the kidneys are still growing, recurrence is frequent and repeated general anaesthesia and radiation exposure should be minimised. Current guidance therefore favours minimally invasive treatment that clears stones effectively at the first session, and percutaneous nephrolithotomy (PCNL) is recommended for larger and complex renal stones in children.2,3 Miniaturisation of the tract (mini-PCNL) was introduced to reduce parenchymal trauma and bleeding while preserving the efficacy of standard PCNL.3 Published experience with paediatric mini-PCNL is encouraging but heterogeneous. Hosseini et al. reported early stone clearance of 90.2% in 112 children, with postoperative fever in 12.5% and transfusion in 3.6%.4 In a Pakistani series of 51 infants, clearance at one month was 90.2% and minor complications occurred in 13.7%.5 Mahmood et al. reported clearance of 93.25% in 115 children, but complications occurred in 25.21%.6 A 2026 randomised trial in children with renal pelvic stones below 2 cm reported one-month clearance of 94.3% after mini-PCNL, comparable to flexible ureteroscopy.7 A meta-analysis of 13 studies found that PCNL techniques offered stone clearance at least comparable to retrograde intrarenal surgery,8 and a recent EAU-YAU systematic review concluded that PCNL is safe and effective in children of all ages, with stone-free rates above 85%.9 However, the same review and a dedicated reporting checklist highlighted inconsistent definitions of "stone-free", variable imaging and incomplete complication grading, which limit comparison between series.9,10 Most published paediatric series include fewer than 200 children, which limits precision for uncommon but serious events such as sepsis, organ injury and death, and local series from Pakistan remain small.5,11,12 A large, locally applicable assessment using strict outcome definitions and explicit denominators is needed to support counselling, operative planning and quality assurance in high-volume stone centres. The objective of this study was to determine single-session stone-free status at 30 days and the frequency and severity of 30-day complications after mini-PCNL in children, and to identify factors associated with residual stones and complications.

This retrospective observational case series with exploratory risk-factor analysis was conducted in the Department of Urology, The Kidney Centre Postgraduate Training Institute, Karachi. Children who underwent mini-PCNL between January 2020 and May 2025 (65 months) were included, and existing follow-up records up to August 2025 were used to capture 90-day outcomes. The study was reported in line with the RECORD recommendations for routinely collected health data and the paediatric PCNL reporting checklist.10 Using the WHO single-proportion formula with an expected stone-free rate of 90.2%,4 95% confidence and 5% absolute precision, the minimum sample size was 136, increased to 152 to allow for 10% incomplete outcome records. A consecutive (census) sampling technique was used, and all eligible children within the study period were included, giving 1000 children, which exceeded the minimum requirement. Inclusion criteria were age below 18 years at index surgery, confirmed renal calculi, mini-PCNL initiated within the study period, and records sufficient to verify age, procedure and date. Children with complex stones, renal anomalies, solitary kidney and previous stone treatment were included. Exclusion criteria were age ≥18 years, standard, micro- or ultra-mini PCNL without an eligible mini-PCNL episode, procedures outside the study period, duplicate episodes and records insufficient to verify eligibility. Missing follow-up alone was not a reason for exclusion. Each child contributed only the earliest eligible (index) episode; subsequent sessions were treated as outcomes. After approval from the institutional ethics review committee, eligible children were identified from theatre registers. Operative, anaesthetic, laboratory, imaging, discharge and outpatient records were abstracted onto a coded proforma. Variables included age, sex, previous stone procedure, renal anomaly or solitary kidney, preoperative urine culture, treated side, largest stone diameter, number of stones, staghorn configuration, multicalyceal involvement, maximum sheath size, number of tracts, access guidance (fluoroscopy, ultrasound or combined), operative and fluoroscopy time, conversion, pre- and postoperative haemoglobin, hospital stay, complications and auxiliary procedures. Mini-PCNL was defined as intended percutaneous stone removal through a 14–22 Fr access sheath. Ten charts were piloted and 10% of records were independently re-checked, with discrepancies resolved by a consultant. The primary outcome was single-session stone-free status, defined as no visible residual fragment on the imaging closest to day 30 (within days 14–42) without any stone-clearing procedure beforehand. Any residual fragment or intervening auxiliary procedure was counted as failure, and absence of qualifying imaging was recorded as unknown; KUB alone for radiolucent stones was not accepted as evidence of clearance. In simultaneous bilateral surgery both kidneys had to be clear. Secondary outcomes were 30-day complications graded according to the treatment required using the modified Clavien–Dindo classification (major complication: grade III–V), fever (≥38°C), transfusion, documented sepsis, urinary leakage, adjacent organ injury, unplanned readmission, death, haemoglobin decrease (preoperative minus first pre-transfusion postoperative value), hospital stay, unplanned auxiliary stone treatment within 90 days and final clearance at 90 days (imaging within days 60–100). Data were analysed using IBM SPSS Statistics version 26. Categorical variables were presented as frequencies and percentages with explicit denominators; the primary proportion was reported with a Wilson 95% confidence interval and with best/worst-case bounds that accounted for children with unknown outcome. Continuous variables were presented as mean ± standard deviation and median (interquartile range). Outcome groups were compared using the chi-square or Fisher exact test and the Mann–Whitney U test. Two prespecified complete-case multivariable logistic regression models were fitted for residual stone/primary failure and for any 30-day complication, with age, largest stone diameter (per 10 mm), staghorn configuration, positive preoperative urine culture, number of tracts and surgery year as covariates; a quadratic age term was added to the complication model to allow a curved age effect. Model fit was assessed by the Hosmer–Lemeshow test, and sensitivity analyses excluded simultaneous bilateral procedures. A two-sided p-value <0.05 was considered significant, and associations were interpreted as exploratory rather than causal. The study was approved by the Institutional Ethics Review Committee of The Kidney Centre Postgraduate Training Institute, Karachi, which granted a waiver of parental consent and child assent for this minimal-risk retrospective record review. Data were anonymised with study identification numbers, and no patient was contacted.

A total of 1000 children were included. The mean age was 10.19 ± 4.75 years (range 6 months–17.9 years); 41 (4.1%) were younger than 2 years, 183 (18.3%) were 2–5 years, 379 (37.9%) were 6–11 years and 397 (39.7%) were 12–17 years. There were 611 (61.1%) boys, giving a male-to-female ratio of 1.6:1. Nearly one in five children had undergone a previous stone procedure, and 12.4% of those with a documented culture had a positive preoperative urine culture. The mean largest stone diameter was 19.81 ± 7.20 mm, and 129 (12.9%) children had staghorn stones. A single tract was used in 888 (88.8%) procedures, and access was purely ultrasound-guided, without fluoroscopy, in 223 (22.3%). Conversion was required in five (0.5%) children: three to standard PCNL and two to open surgery (Table-I). TABLE-I Baseline, stone and operative characteristics of children undergoing mini-PCNL (n=1000) Variable n (%) or value Valid n Demographic and clinical Age (years), mean ± SD; median (IQR) 10.19 ± 4.75; 10.5 (6.5–14.2) 1000 Male sex 611 (61.1) 1000 Previous stone procedure 189 (18.9) 1000 Renal anomaly or solitary kidney 83 (8.3) 1000 Positive preoperative urine culture 120 (12.4) 968 Stone characteristics Largest stone diameter (mm), mean ± SD 19.81 ± 7.20 1000 Number of stones, median (IQR) 1 (1–2) 1000 Staghorn configuration 129 (12.9) 1000 Multiple calyces involved 508 (50.8) 1000 Side: right / left / bilateral 494 (49.4) / 467 (46.7) / 39 (3.9) 1000 Operative characteristics Sheath 14–16 Fr / 18 Fr / 20 Fr / 22 Fr 104 (10.4) / 327 (32.7) / 295 (29.5) / 274 (27.4) 1000 Single tract / two tracts / three tracts 888 (88.8) / 105 (10.5) / 7 (0.7) 1000 Guidance: fluoroscopy / ultrasound / combined 382 (38.2) / 223 (22.3) / 395 (39.5) 1000 Operative time (minutes), mean ± SD 52.34 ± 15.22 1000 Fluoroscopy time (seconds), mean ± SD 60.09 ± 40.30 970 Conversion (standard PCNL / open) 5 (0.5) (3 / 2) 1000 Haemoglobin decrease (g/dL), mean ± SD 0.60 ± 0.37 953 Hospital stay (days), mean ± SD; median (IQR) 3.81 ± 1.20; 4 (3–4) 1000 IQR: interquartile range; PCNL: percutaneous nephrolithotomy; SD: standard deviation. Percentages are of valid (documented) records. The primary endpoint was assessable in 947 (94.7%) children, and 53 (5.3%) lacked qualifying imaging. Follow-up imaging was performed at a median of 30 days (IQR 28–31), most often by ultrasound alone or ultrasound with KUB. Single-session stone-free status was achieved in 865 of 947 children (91.3%; 95% CI 89.4–93.0). When all 1000 eligible children were considered, the stone-free rate ranged from 86.5% (if all unknown outcomes were failures) to 91.8% (if all were successes). Of the 82 primary failures, 64 had a residual fragment on imaging and 18 had received a stone-clearing procedure before assessment. Unplanned auxiliary treatment within 90 days was needed in 61 of 916 (6.7%) children, and final clearance at 90 days was documented in 880 of 911 (96.6%) (Table-II). TABLE-II Efficacy outcomes after mini-PCNL Outcome n/N (%) Primary endpoint assessable 947/1000 (94.7) Single-session stone-free at 30 days 865/947 (91.3); 95% CI 89.4–93.0 Best/worst-case stone-free rate (all eligible) 86.5% to 91.8% Residual fragment on qualifying imaging 64/947 (6.8) Stone-clearing treatment before assessment 22/1000 (2.2) Imaging: US / US + KUB / low-dose CT / KUB 318 (33.6) / 314 (33.2) / 164 (17.3) / 151 (15.9) Unplanned auxiliary treatment by day 90 61/916 (6.7) Shock wave lithotripsy 24 (2.6) Second-look PCNL 22 (2.4) Flexible ureteroscopy 15 (1.6) Final stone-free at 90 days 880/911 (96.6) CI: confidence interval (Wilson); CT: computed tomography; KUB: plain abdominal radiograph; US: ultrasound. Imaging percentages are of 947 assessable children. Complication status at 30 days was documented in 956 children. At least one complication occurred in 157 (16.4%), and most were minor: 69 (7.2%) were Clavien grade I and 76 (7.9%) grade II (Figure-1). Major complications (grade III–V) occurred in 12 (1.3%) children and comprised five adjacent organ injuries and one urinary leak requiring intervention under general anaesthesia (grade IIIb), one urinary leak managed by stent insertion without general anaesthesia (grade IIIa), four episodes of sepsis requiring intensive care (grade IVa) and one in-hospital death after sepsis (grade V). Fever was the most frequent event, and transfusion was required in 1.5% (Table-III). FIGURE-1 Distribution of the highest postoperative Clavien–Dindo grade within 30 days (percentages of 956 children with documented complication status) TABLE-III Thirty-day complications after mini-PCNL Complication n/N (%) Any documented complication 157/956 (16.4) Clavien grade I 69/956 (7.2) Clavien grade II 76/956 (7.9) Clavien grade IIIa / IIIb 1 (0.1) / 6 (0.6) Clavien grade IVa / V 4 (0.4) / 1 (0.1) Major complication (grade III–V) 12/956 (1.3) Fever ≥38°C 116/951 (12.2) Blood transfusion 15/1000 (1.5) Documented sepsis 8/946 (0.8) Urinary leakage 13/944 (1.4) Adjacent organ injury 5/1000 (0.5) Unplanned readmission 19/946 (2.0) Death within 30 days 1/944 (0.1) Denominators differ because events without adequate documentation were coded as unknown rather than absent. Children may have had more than one event; grading reflects the highest grade per child. On univariate analysis, primary failure was more frequent in children with staghorn stones (26.0% vs 6.1%; p<0.001) and multicalyceal stones (11.6% vs 5.6%; p=0.001). Children with residual stones had larger stones (median 23.8 vs 19.0 mm; p<0.001), longer operative time (median 56 vs 51 minutes; p=0.007) and more often required more than one tract (19.5% vs 10.3%; p=0.012), whereas age and sheath size did not differ. Any complication was more frequent after a positive preoperative urine culture (25.7% vs 15.0%; p=0.004); no other baseline characteristic was associated with complications on univariate analysis (Table-IV). Children with unknown primary outcome had slightly smaller stones (median 15.9 vs 19.3 mm; p=0.048) and had more often undergone surgery in later years (p=0.007), but did not differ in age, staghorn configuration or culture status. TABLE-IV Univariate factors associated with primary failure and any 30-day complication Factor Primary failure n/N (%) p Any complication n/N (%) p Staghorn: yes / no 32/123 (26.0) / 50/824 (6.1) <0.001 24/126 (19.0) / 133/830 (16.0) 0.393 Multiple calyces: yes / no 56/481 (11.6) / 26/466 (5.6) 0.001 85/487 (17.5) / 72/469 (15.4) 0.381 Positive culture: yes / no 13/110 (11.8) / 65/806 (8.1) 0.186 29/113 (25.7) / 122/812 (15.0) 0.004 Previous procedure: yes / no 15/181 (8.3) / 67/766 (8.7) 0.843 27/181 (14.9) / 130/775 (16.8) 0.544 Renal anomaly: yes / no 6/81 (7.4) / 76/866 (8.8) 0.675 12/78 (15.4) / 145/878 (16.5) 0.796 Bilateral: yes / no 3/37 (8.1) / 79/910 (8.7) 1.000† 7/38 (18.4) / 150/918 (16.3) 0.734 Stone diameter (mm)‡ 23.8 (18.3–31.3) vs 19.0 (14.4–23.7) <0.001 18.3 (12.9–23.9) vs 19.3 (14.8–24.1) 0.116 Operative time (min)‡ 56 (46–67) vs 51 (41–62) 0.007 49 (41–60) vs 52 (41–63) 0.265 Age (years)‡ 10.2 (5.9–13.9) vs 10.6 (6.4–14.2) 0.346 11.1 (7.4–14.2) vs 10.2 (6.2–14.1) 0.190 Categorical factors compared by Pearson chi-square test; †Fisher exact test. ‡Median (IQR) in children with vs without the outcome, compared by Mann–Whitney U test. In multivariable analysis (Table-V; Figure-2), larger stone diameter was the only independent predictor of residual stones (aOR 2.00 per 10 mm; 95% CI 1.33–3.01; p=0.001), while staghorn configuration showed a borderline association (aOR 2.09; p=0.053). For complications, staghorn configuration (aOR 2.37; 95% CI 1.22–4.60) and positive preoperative urine culture (aOR 1.92; 95% CI 1.20–3.07) were independent predictors. Age showed a curved relationship with complication risk, which rose to a peak at around 11 years and declined thereafter, and larger stone diameter was inversely associated with complications after adjustment for staghorn configuration. Both models showed adequate fit, and the results were unchanged after excluding 39 bilateral procedures (stone diameter for residual stones: aOR 2.03; culture for complications: aOR 2.07; staghorn for complications: aOR 2.14). TABLE-V Multivariable logistic regression for primary failure and any 30-day complication Variable aOR (95% CI) p Model 1: residual stone/primary failure Age (per year) 0.96 (0.91–1.01) 0.116 Largest stone diameter (per 10 mm) 2.00 (1.33–3.01) 0.001 Staghorn configuration 2.09 (0.99–4.43) 0.053 Positive preoperative urine culture 1.47 (0.75–2.87) 0.260 Total access tracts (per tract) 1.06 (0.55–2.01) 0.871 Surgery year (per year) 1.05 (0.90–1.22) 0.536 Model 2: any 30-day complication Age (per year) 1.28 (1.06–1.54) 0.010 Age squared 0.989 (0.980–0.998) 0.014 Largest stone diameter (per 10 mm) 0.65 (0.48–0.89) 0.007 Staghorn configuration 2.37 (1.22–4.60) 0.011 Positive preoperative urine culture 1.92 (1.20–3.07) 0.007 Total access tracts (per tract) 0.88 (0.51–1.52) 0.633 Surgery year (per year) 1.05 (0.94–1.18) 0.382 aOR: adjusted odds ratio. Model 1: n=916, 78 events; Nagelkerke R² 0.118; Hosmer–Lemeshow p=0.242. Model 2: n=925, 151 events; Nagelkerke R² 0.043; Hosmer–Lemeshow p=0.393. Complete-case analyses. FIGURE-2 Forest plot of adjusted odds ratios for primary failure and any 30-day complication (filled markers: p<0.05; age terms of the complication model are shown in Table-V)

In this series of 1000 children, mini-PCNL achieved a single-session stone-free rate of 91.3%, rising to 96.6% at 90 days, with complications that were mostly minor and a major complication rate of 1.3%. To our knowledge, this is one of the largest single-centre paediatric mini-PCNL series reported from Pakistan, and the strict definition used here, which counted any visible fragment or any intervening procedure as failure, makes the clearance estimate conservative. Even under the worst-case assumption that all children without qualifying imaging had failed, clearance remained 86.5%. Our stone-free rate is comparable to that of recent paediatric mini-PCNL series. Hosseini et al. and Ahmad et al. each reported clearance of 90.2%,4,5 Mahmood et al. reported 93.25%,6 and the randomised trial by Mahmoud et al. reported 94.3% for pelvic stones below 2 cm.7 Ultrasound-guided series from China reported initial clearance of 85.5–86.4% and final clearance of 92.5–95.2%,13,14 which mirrors the increase from 91.3% to 96.6% after auxiliary treatment in our study. Local series have reported lower clearance of 69.2% in children with stones of 2.5 cm or more11 and 78.2% in a Khyber Pakhtunkhwa cohort,12 whereas Khan et al. reported complete clearance in most of their 12 children treated in Sindh.15 These differences probably reflect stone burden, imaging modality and the definition of clearance rather than true differences in technique, which is consistent with the reporting inconsistencies identified by the EAU-YAU review.9,10 The need for auxiliary treatment in 6.7% of our children is also in keeping with reports in which residual fragments after primary mini-PCNL were cleared with ureteroscopy or a second session.16,17 Stone burden was the strongest determinant of efficacy. Each 10 mm increase in stone diameter doubled the odds of residual stones, and failure was four times more frequent in staghorn than in non-staghorn stones on univariate analysis. The attenuation of the staghorn effect after adjustment (aOR 2.09; p=0.053) is expected because staghorn configuration and stone size are closely related. Similar patterns have been reported by Zanetti et al., in whom clearance fell to 63% for staghorn stones and to 50% for large stone volumes,18 and by Al Mousawi et al., who achieved only 73.2% early clearance in large and complex stones before ancillary treatment.16 These findings support stone-specific counselling, planned second-look procedures or combined approaches for staghorn and multicalyceal stones in children. The overall complication rate of 16.4% falls within the range of 13.7–25.2% reported in recent mini-PCNL series,5,6 and 92.4% of complicated cases were Clavien grade I–II. The transfusion rate of 1.5% and mean haemoglobin decrease of 0.6 g/dL compare favourably with transfusion rates of 3.5–3.6% reported by Hosseini et al. and Mahmood et al.4,6 and 19.2% in a local series of large stones.11 Karkin et al. found a significantly smaller haemoglobin decrease after mini-PCNL than after standard PCNL in children, without loss of efficacy,19 which supports the use of smaller tracts. The major complication rate of 1.3% is lower than the 12.1% reported in an ultrasound-guided series,13 although grading conventions vary considerably between studies.9,10 Notably, purely ultrasound-guided access was used in 22.3% of our children, which avoided radiation exposure, an advantage also highlighted by Hong et al.13,14 The mean operative time of 52 minutes and median hospital stay of 4 days are comparable to those of other series.6,19 Positive preoperative urine culture was associated with an almost two-fold increase in complications, independent of stone burden, and sepsis occurred in 0.8% of children with one sepsis-related death. In a cohort of 963 patients, Yang et al. identified positive preoperative urine culture and longer operative time as independent risk factors for infection after PCNL, with nearly one-third of infections progressing to septic shock.20 The IAU guideline recommends preoperative urine culture and culture-directed antibiotic treatment before PCNL,3 and in a Pakistani PCNL series infective events were among the leading complications.21 Our findings support strict documentation of sterile urine, targeted antibiotic therapy and early recognition of sepsis in children with bacteriuria. Staghorn configuration was also independently associated with complications, probably reflecting longer manipulation, the need for multiple tracts and the frequent infective nature of these stones.18 Two associations require cautious interpretation. Complication risk followed a curved relationship with age, peaking around early adolescence, and larger stone diameter was inversely associated with complications after adjustment for staghorn configuration. These may reflect residual confounding by stone type, surgeon selection or more intensive observation of smaller children rather than true effects, and the low explanatory power of the complication model (Nagelkerke R² 0.043) indicates that most complication risk was not captured by the measured variables. These exploratory findings should be tested in prospective studies before they inform patient selection. This study has limitations. It was a single-centre retrospective review, so documentation depended on routine records, and outcome information was missing in 5.3% for the primary endpoint and up to 8.9% for 90-day outcomes; children with unknown outcomes had slightly smaller stones and were more often treated in later years. Follow-up imaging was heterogeneous, and only 17.3% of children underwent low-dose CT, so small residual fragments may have been under-detected by ultrasound, although KUB-only assessment of radiolucent stones was not accepted. Events managed at other hospitals may have been missed, there was no comparison group, and stone composition, metabolic evaluation and long-term renal function were not assessed. Multicentre prospective studies with standardised CT-based follow-up are required.

Mini-PCNL in children achieved a single-session stone-free rate of 91.3% and final clearance of 96.6%, with mainly minor complications and a major complication rate of 1.3%. Larger stone diameter predicted residual stones, while staghorn configuration and positive preoperative urine culture predicted complications; these factors should guide counselling and perioperative planning. CONFLICT OF INTEREST The authors declare no conflict of interest. SOURCE OF FUNDING This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors. ACKNOWLEDGEMENTS The authors acknowledge the staff of the Department of Urology and the medical records section of The Kidney Centre Postgraduate Training Institute, Karachi, for their assistance with data retrieval.

1. Pecoraro L, Zuccato A, Vitella R, Pietrobelli A, Piacentini G, Brugnara M. Pediatric nephrolithiasis: A changing landscape through time and space. Medicina (Kaunas). 2024; 60(12):1993. DOI: 10.3390/medicina60121993 2. European Association of Urology. EAU Guidelines on Urolithiasis [Internet]. Arnhem: EAU Guidelines Office; 2025 [cited 2026 Oct 13]. Available from: https://uroweb.org/guidelines/urolithiasis 3. Zeng G, Zhong W, Mazzon G, Choong S, Pearle M, Agrawal M, et al. International Alliance of Urolithiasis (IAU) guideline on percutaneous nephrolithotomy. Minerva Urol Nephrol. 2022; 74(6):653-68. DOI: 10.23736/S2724-6051.22.04752-8 4. Hosseini MM, Irani D, Altofeyli A, Eslahi A, Basiratnia M, Haghpanah A, et al. Outcome of mini-percutaneous nephrolithotomy in patients under the age of 18: An experience with 112 cases. Front Surg. 2021; 8:613812. DOI: 10.3389/fsurg.2021.613812 5. Ahmad T, Minallah N, Khaliq N, Rashid H, Syed M, Almuradi MAA. Safety and efficacy of minimally invasive percutaneous nephrolithotomy for infantile nephrolithiasis. Single centre experience from Pakistan. Front Pediatr. 2023; 10:1035964. DOI: 10.3389/fped.2022.1035964 6. Mahmood SN, Said SHA, Mohammed RO, Jaafar MS. Safety and efficacy of mini-percutaneous nephrolithotomy in management of renal stones in pediatric age group. BMC Nephrol. 2025; 26:111. DOI: 10.1186/s12882-025-04031-4 7. Mahmoud O, Abdallah M, Abdellatif A, Mostafa AH, Albudairat A, Elmarakbi AA, et al. Comparative evaluation of flexible ureterorenoscopy and mini-percutaneous nephrolithotomy for the management of renal pelvic stones less than 2 cm with high attenuation value in pediatric patients: A prospective randomized study. Urolithiasis. 2026; 54:48. DOI: 10.1007/s00240-026-01938-x 8. Yuan Y, Liang Y, Li K, Ho Y, Wu Q, Zhao Z. A meta-analysis: Retrograde intrarenal surgery vs. percutaneous nephrolithotomy in children. Front Pediatr. 2023; 11:1086345. DOI: 10.3389/fped.2023.1086345 9. Quiroz Madarriaga Y, Dönmez Mİ, Lammers RJM, Bañuelos Marco B, Baydilli N, Bindi E, et al. Present insights and future perspectives in pediatric percutaneous nephrolithotomy: A systematic review by the EAU-YAU Pediatric Urology Working Group. J Endourol. 2025; 39(7):659-70. DOI: 10.1089/end.2024.0727 10. Juliebø-Jones P, Ulvik Ø, Beisland C, Somani BK. Paediatric percutaneous nephrolithotomy (P-PCNL) reporting checklist. Scand J Urol. 2023; 58:115-9. DOI: 10.2340/sju.v58.13392 11. Majid F, Rasool M, Usman M. Safety and efficacy of mini percutaneous nephrolithotomy using smaller nephroscope for kidney stones in children. J Bahria Univ Med Dent Coll. 2026; 16(3):705-10. DOI: 10.51985/JBUMDC2025733 12. Khan W, Khan TS, Khan RA, Khalid M, Ahmad A, Khan AI. Efficacy of percutaneous nephrolithotomy in pediatric renal stone clearance in Khyber Pakhtunkhwa: A cross-sectional analytical study. Pak J Health Sci. 2025; 6(7):215-20. DOI: 10.54393/pjhs.v6i7.3344 13. Hong Y, Yu L, Huang X, An L, Xiong L, Xu T, et al. Outcome of ultrasonography-guided percutaneous nephrolithotomy for the management of pediatric urolithiasis. J Endourol. 2025; 39(2):146-50. DOI: 10.1089/end.2023.0771 14. Hong Y, Ye H, Yang B, Xiong L, An L, Ma K, et al. Ultrasound-guided minimally invasive percutaneous nephrolithotomy is effective in the management of pediatric upper ureteral and renal stones. J Invest Surg. 2021; 34(10):1078-82. DOI: 10.1080/08941939.2020.1764154 15. Khan KA, Memon WA, Jat JA, Jaffery AR, Arain AH, El Khalid S. Mini-PCNL in pediatric patients with large renal stones: A safety data. Liaquat Med Res J. 2022; 4(3). DOI: 10.38106/LMRJ.2022.4.3-04 16. Al Mousawi S, Guzel R, Zaid M, Eryildirim B, Sarica K. Minipercutaneous nephrolithotomy in the management of large and complex renal calculi in children: How effective is it? J Endourol. 2023; 37(4):387-93. DOI: 10.1089/end.2022.0508 17. Mahmoud MA, Shawki AS, Abdallah HM, et al. Use of retrograde intrarenal surgery (RIRS) compared with mini-percutaneous nephrolithotomy (mini-PCNL) in pediatric kidney stones. World J Urol. 2022; 40:3083-9. DOI: 10.1007/s00345-022-04186-x 18. Zanetti SP, Jannello LMI, Quistini A, Ciamarra F, Passarelli F, Ripa F, et al. Tackling complex kidney stones in children: The role of vacuum-assisted mini-PCNL - a single-center study. World J Urol. 2026; 44:314. DOI: 10.1007/s00345-026-06395-0 19. Karkin K, Aydamirov M, Aksay B, Kaplan E, Gürlen G, Altunkol A, et al. Comparison of two percutaneous nephrolithotomy methods for the treatment of pediatric kidney stones: Mini-percutaneous nephrolithotomy and standard percutaneous nephrolithotomy. Arch Ital Urol Androl. 2024; 96(2):12369. DOI: 10.4081/aiua.2024.12369 20. Yang Z, Lin D, Hong Y, Hu M, Cai W, Pan H, et al. The effect of preoperative urine culture and bacterial species on infection after percutaneous nephrolithotomy for patients with upper urinary tract stones. Sci Rep. 2022; 12:4833. DOI: 10.1038/s41598-022-08913-7 21. Afnan M. An analysis of percutaneous nephrolithotomy (PCNL) performed at the Institute of Kidney Disease, Pakistan: Stone clearance and complications. Cureus. 2024; 16(12):e75430. DOI: 10.7759/cureus.75430]