Acute urinary retention in children: causes and the role of bladder catheterization and ultrasonogram.

BACKGROUND: Acute urinary retention in children is uncommon and can be related to several causes. The role of abdominal ultrasound and catheterization is controversial. We aimed to identify the most common causes of acute urinary retention in children, focusing, particularly on the role of bladder catheterization and the diagnostic value of acute ultrasound. METHODS: We retrospectively analyzed all consecutive children admitted to our emergency department with acute urinary retention from 2010 to 2020. Post-operative acute urinary retention, neonatal age, and known urological or neurological disorders were excluded. Diagnostic workup and management were adopted in each patient. Results were compared in patients with more and less than 5 years old. RESULTS: 193 patients were included. Median age was 3 (2-16) years; 53.4% were girls. Ultrasound evaluation was performed in (129/193; 66.8%) patients, more commonly <5-year-old (74% vs. 26%, P<0.01). A previously unknown urological condition was detected in (16/129; 12%). The majority of patients (124/193; 64%) were managed without bladder catheterization. These patients were significantly younger than the remainder (3- vs. 4-year-old, P<0.01) and the most common diagnosis was external genitalia inflammation (53%). Of the remaining patients, (34/69; 49%) restored spontaneous micturition after a single catheterization, whereas 35 required admission. The latter were more commonly males (32%, P=0.01), with higher incidence of abnormal ultrasound (33% vs. 7%, P<0.001). CONCLUSIONS: Acute urinary retention in commonly due to external genitalia inflammation, particularly in patients <5-year-old, and can be generally managed, without bladder catheterization. Abdominal ultrasound is an important diagnostic tool, that should be performed only in selected cases.

Voiding cystourethrography in patients undergoing endoscopic decompression of duplex system ureteroceles: to do or not to do?

OBJECTIVE: To assess the role of voiding cystourethrography (VCUG) in patients with duplex system ureterocele (DSU) undergoing endoscopic decompression (ED). MATERIALS AND METHODS: This is a retrospective study of 75 consecutive patients with DSU undergoing ED [median (range) age, 6 (1-148) months]. Patients were divided into 3 groups, 33 with a VCUG showing vesicoureteral reflux (VUR) before ED (VUR-group), 22 with a VCUG negative for VUR (No-VUR-group), and 20 who did not undergo a VCUG (No-VCUG-group). Secondary surgery (SS) rate was compared among groups. RESULTS: Groups were comparable for baseline characteristics. SS rate was 82% (27/33) in VUR-group vs. 32% (7/22) in the No-VUR-group (p = 0.0001), and 25% (5/20) in the No-VCUG-group (p = 0.001 vs. VUR-group, and 1 vs. No-VUR-group). In the VUR-group, 9 patients underwent preemptive endoscopic treatment of VUR during ED and SS rate was 44% (4/9) vs. 96% (23/24) in the remainder, p= 0.003. In the No-VCUG-group, a VCUG was performed during follow-up in 9/15 patients and showed reflux in all, although only 2 of these developed a (single) urinary tract infections. CONCLUSIONS: SS rate was significantly higher in patients with preoperative VUR. Instead, it was not significantly different between patients without VUR and those who did not undergo a VCUG before ED, despite all the latter who underwent a VCUG during follow-up had evidence of VUR generally in the absence of symptoms. In our opinion, a VCUG could be limited to patients developing symptoms after ED. If a VCUG is performed before ED, a preemptive treatment of VUR should be taken into consideration.

Risk Factors for Failure of Endoscopic Balloon Dilatation of Primary Obstructive Megaureter: Single-Center 12-Year Experience with 123 Cases.

Purpose: To review our experience with >100 patients with primary obstructive megaureter (POM) undergoing endoscopic balloon dilatation (EBD) and a follow-up of up to 12 years and determine potential risk factors for failure. Our hypothesis is that EBD allows for long-term treatment in >80% of patients, and its effectiveness decreases in more severe cases. Methods: This is a retrospective study of 123 consecutive patients (131 ureters) undergoing EBD from 2009 to 2021. Indications for EBD included symptoms, worsening dilatation, and/or renal function impairment. Clinical characteristics, complications, and outcomes, including those in the patients with >5-year follow-up, were described. Preoperative and intraoperative markers of severity chosen a priori were tested as risk factors for failure. Failure was defined as the need for ureteral reimplantation after EBD. Results: EBD was feasible in 121 of 123 (98%) patients, regardless of age. After a median follow-up of 38 (9-143) months, EBD was effective in 84.5% of cases. Failures generally occurred in the 1st year after EBD and were seldom associated with permanent loss of renal function. Of the 66 patients with follow-up >5 years, EBD was effective in 56 patients. No preoperative characteristic proved to be a risk factor for failure. The intraoperative absence of a ring was the only significant risk factor for failure, odd ratio 117.86 (95% confidence interval 6.27-2215.84). Conclusions: EBD was feasible and definitive treatment in 85% of our cases, regardless of age. Since this study did not identify preoperative factors to help the clinicians in patient selection, we consider EBD a viable initial procedure in all patients with POM who require surgical intervention, especially in infants.

Vacuum-assisted Mini-percutaneous Nephrolithotomy for 2-3-cm Renal Stones: A Comparative Study with Retrograde Intra-renal Surgery.

PURPOSE: To compare vacuum-assisted percutaneous nephrolithotomy (VAmini-PCNL) with retrograde intra-renal surgery (RIRS) for the treatment of renal stones measuring 2-3 cm in diameter. MATERIAL AND METHODS: This retrospective study included children receiving treatment for pyelocalyceal stones of 2-3 cm in diameter from November 2018 to September 2022. Consecutive patients undergoing VAmini-PCNL after 2020 were compared with a historically matched group undergoing RIRS. VAmini-PCNL was performed using a 12-Ch nephroscope through a 16-Ch vacuum ClearPetra access sheet. RIRS was performed using a flexible ureteroscope through a ureteral sheath. The endpoints included the need for pre-stenting, duration of surgery, complications, stone-free rate (SFR), and need for secondary procedures. RESULTS: The patients were grouped into two with 15 patients for each group. VAmini-PCNL group was not different from the RIRS one for age at surgery [median (range) 6.6 (1-12)years vs. 7.7 (1.5-14)years], and stone diameter [median (range) 2.4 (2.0-2.9)cm vs. 2.3 (2.1-2.8)cm] and density [median (range) 577.5 (421-1068) vs. 541.5 (462-927) Hunsfield Units]. Pre-stenting was necessary in five RIRS patients (33 %). The median duration of surgery was 85.3 (76-112)min for VAmini-PCNL vs. 150.6 (132-167)min for RIRS, p = 0.00001. No major complications were observed. The SFR was 100 % after VAmini-PCNL and 60 % after RIRS, p = 0.02. All residual fragments were removed with a second RIRS. CONCLUSION: VAmini-PCNL was feasible and safe in children aged >1 year. It allowed for a significantly higher SFR despite a significantly shorter operative time than RIRS, which also requires pre-stenting in one-third of patients and a second RIRS in 40 % of cases. LEVEL OF EVIDENCE: III.

Where is the testis? The role of ultrasound and diagnostic laparoscopy for Crossed Testicular Ectopia (CTE): Case report and review of literature.

Crossed Testicular Ectopia (CTE) or transverse testicular ectopia is an anecdotic urogenital anomaly in which both testes are located on the same side, generally associated with a patent processus vaginalis (PPV). The condition can be detected by ultrasound. Nevertheless, the diagnosis is often missed preoperatively and CTE is recognized intraoperatively. Controversy exists regarding management and the role of diagnostic laparoscopy. The surgical technique depends on the anatomy of vas, vessels and testis found on surgical exploration. Diagnostic laparoscopy can be useful to rule out a vanishing testis and detect Müllerian remnants. We present the case of 8-months infant with no palpable testis on the right side and no signs of inguinal hernia, reporting the management and reviewing the scarce existing literature in this regarding. KEY WORDS: Crossed Testicular Ectopia, Laparoscopy, Ectopia, Testis, Transverse Testicular Ectopia, Urogenital Abnormalities.

Pyelo-ureteral junction obstruction in poorly functioning kidneys: Does conservative management play a role in pediatric patients?

Background: Management of Pyelo-ureteral Junction Obstruction (PUJO) in poorly functioning kidneys in pediatric patients is still controversial, particularly regarding the role of conservative treatment. Aim: To evaluate and present the outcomes of internal diversion and follow-up results of a small series of pediatric patients with UPJO in poorly functioning kidneys. Study design: Retrospective review of 17 consecutive patients with unilateral PUJO in kidneys with Differential Renal Function (DRF) <20% undergoing temporary internal urinary diversion between 2009 and 2021 at a single tertiary center. DRF was reassessed after 1-3 months of diversion and subsequent management was conservative or surgical (pyeloplasty or nephrectomy) based on surgeon's and family's preferences without randomization. Results: After a trial of internal urinary diversion, 4/17 patients (23%) showed a DRF increase ≥5% (9%-12%), up to a maximum DRF of 28%, 3 underwent pyeloplasty, while 1 was managed conservatively. The remaining 13 patients showed no differential renal function improvement after diversion, and 7 were managed expectantly while 6 surgically (4 pyeloplasty, 2 nephrectomy). Overall, nine patients (53%) were managed surgically and 8 (47%) expectantly After a median (range) follow-up of 3.1 (0.3-7.9) years, no significant difference was observed between groups regarding symptoms (p = 0.205), need for further surgery (p = 1.000), and renal function (p = 1.000). Discussion: Although fraught with the limitation of a small sample size, this is the first study reporting on the conservative management of this controversial group of patients. Conclusion: In present pediatric series of pyelo-ureteral Junction obstruction in poorly functioning kidneys with differential renal function <20%, function recovery after a trial of internal urinary diversion was quite exceptional, and no difference was observed in outcome between patients managed surgically and conservatively after stent removal.

Endoscopic balloon dilatation for the treatment of primary obstructive megaureter <24 months of age: Does the size of the balloon influence results?

INTRODUCTION: Endoscopic balloon dilatation (EBD) can be performed with different catheters and its durability is still controversial. This study aimed to compare long-term results of EBD performed <24 months of age using balloons of 4 mm vs. 6 mm in diameter. MATERIALS AND METHODS: Retrospective study of consecutive patients with unilateral primary obstructive megaureter (POM) undergoing EBD <24 months of age by two surgeons from 01/2009 to 12/2020. The technique was consistent, but for balloon diameter, which was 4 mm in group A vs. 6 mm in group B. End-points included peri-operative complications, success rate (improving dilatation and non-obstructive drainage on 9-month scintigraphy), and long-term outcome (need for reimplantation and diameter of retrovesical ureter at last ultrasound). RESULTS: The procedure was completed in all planned patient. Group A included 15 patients and Group B 30 patients. Groups were not significantly different for age (p < 0.09), gender (p < 0.1), laterality (p < 0.7), and preoperative median ureteral diameter (p = 0.08). No perioperative complications occurred. Four group A patients required a cutting balloon to achieve a satisfactory dilatation of the vesicoureteral junction (p = 0.009). After a median (range) follow-up of 70 (19-155) months, success rate was 73.3% vs. 83.3% (p = 0.45), 4/15 group A and 5/30 group B patients required reimplantation within 2 years of EBD. In successful cases, median (range) ureteral diameter at last follow-up was 6 (0-17) mm vs. 5 (0-14) mm, which was significantly better than preoperative value (p = 0.003 and p < 0.001, respectively), but not significantly different (p = 0.8) between groups. DISCUSSION: EBD is an umbrella term that encompasses many technical variations, which can be key for success. Although limited by the small numbers and the comparison of patients treated over two subsequent periods, this is the first study focusing on the role of balloon size. CONCLUSIONS: The diameter of the balloon did not influence significantly long-term results, but the 6 mm balloon slightly increased the success rate of EBD to 83.3% and eliminated the need for cutting balloons to achieve a satisfactory dilatation.

Pre and postoperative imaging in patients undergoing pyeloplasty: A survey of current adult and paediatric practice.

BACKGROUND: Imaging to be used during the workup and follow-up of patients undergoing pyeloplasty is still controversial. Present survey aimed at assessing variations in pre- and post-operative imaging between adults and paediatric specialists in patients undergoing pyeloplasty. METHODS: A survey of members of the 'Italian Society of Urology' (SIU) and the 'Italian Society of Paediatric Urology' (SIUP) was conducted using an online platform. RESULTS: Respondents included 87 (74.4%) adult and 30 (25.6%) paediatric specialists. Adult specialists were significantly more likely to use a CT scan during preoperative workup (p = 0.001) and postoperative follow-up (p < 0.001). In contrast, paediatric specialists were significantly more likely to recommend voiding cystourethrography during the workup (p < 0.001) and an MRI in cases requiring additional diagnostic study (<0.001). Adult specialists reported to deal significantly more commonly with symptomatic or complicated hydronephroses (p < 0.001). The majority of respondents recommend an ultrasound scan at 1-3 months as first postoperative investigation. Two-third also recommended a nuclear scintigraphy, but 67.8% of adult specialists recommended to perform it within 6 months of surgery whereas 76.7% of paediatric specialists between 6 and 12 months (p < 0.001). CONCLUSIONS: Present survey suggests quite a significant variation between adult and paediatric specialists in pre- and post-operative assessment of patients requiring pyeloplasty. This may just reflect different attitudes that could be improved with appropriate studies, or essential differences in the condition or the characteristics of treated patients. In any case, such differences are important and should be taken into account.

Minimally Invasive Laser Treatment of Ureterocele.

Introduction: Ureterocelemay cause severe pyelo-ureteral obstruction with afebrile urinary tract infections in infants and children. Early decompressive treatment is advocated to reduce the risk of related renal and urinary tract damage. Endoscopic techniques of incision have been offered utilizing diathermic electrode. We adopted laser energy to release the obstruction of the ureterocele and reduce the need of further surgery. Our technique is described and results are presented, compared with a group of matched patients treated by diathermic energy. Materials and methods: Decompression was performed by endoscopic multiple punctures at the basis of the ureterocele. Holmium YAG Laser was utilized with 0.5-0.8 joule energy, through 8-9.8F cystoscope under general anesthesia. The control group received ureterocele incision by diathermic energy through pediatric resettoscope. Foley indwelling catheter was removed after 18-24 h. Renal ultrasound was performed at 1, 3, 6, and 12 months follow-up. Voiding cysto-urethrogram and radionuclide renal scan were done at 6-18 months in selected cases. Statistical analysis was utilized for data evaluation. Results: From January 2012 to December 2017, 64 endoscopic procedures were performed: 49 were ectopic and 15 orthotopicureteroceles. Fifty-three were in duplex systems, mostly ectopic. Mean age at endoscopy was 6.3 months (1-168). Immediate decompression of the ureterocele was obtained, but in five cases (8%) a second endoscopic puncture was necessary at 6-18 months follow-up for recurrent dilatation. Urinary tract infections and de novo refluxes occurred in 23.4 and 29.7% in the study group, compared to 38.5 and 61.5% in the 26 controls (p < 0.05). Further surgery was required in 12 patients (18%) at 1-5 years follow-up (10 in ectopic ureteroceles with duplex systems): seven ureteral reimplantation for reflux, five laparoscopic hemy-nephro-ureterectomy. Orthotopic ureteroceceles had better outcome. Secondary surgery was necessary in 13 patients (50.0%) of control group (p < 0.05). Conclusions: Early endoscopic decompression should be considered first line treatment of obstructing ureterocele in infants and children. Multiple punctures at the basis of the ureterocele, performed by low laser energy, is resulted a really minimally invasive treatment, providing immediate decompression of the upper urinary tract, and reducing the risk of further aggressive surgery.

Primary obstructive megaureter in infants: our experience with endoscopic balloon dilation and cutting balloon ureterotomy.

The management of primary obstructive megaureter (POM) is usually conservative, at least in the first year of life. Nevertheless, in high-grade POMs with increasing dilation, obstructive patterns found at renography, or cases involving decreased renal function, there is a clear indication for surgery. From January 2009 to March 2013, 12 patients, aged 6 to 12 months (mean 8 months), were treated endoscopically for POM. At the procedure, a clear stenotic ring was identified in 10 of the 12 patients, and a simple endoscopic high-pressure balloon dilation (EHPBD) was well performed in 7 patients. In the three cases with persistent ring, a cutting balloon ureterotomy (CBU) was then performed, resulting in the immediate and complete disappearance of the stenosis. In two cases, no ring could be seen at the procedure, and they showed no improvement at the follow-up. The mean follow-up was 21 months. Considering the whole series of patients treated endoscopically, the overall success rate of EHPBD+CBU was 83%. Patients with POM can be treated endoscopically. In the case of a persistent ring that is unresponsive to EHPBD, CBU seems to provide a valid definitive treatment of POM.

Renal function adaptation up to the fifth decade after treatment of children with unilateral renal tumor: a cross-sectional and longitudinal study.

BACKGROUND: Mild-to-moderate renal function loss may be an independent risk factor for cardiovascular disease and overall mortality. As in adults with renal carcinoma nephrectomy is associated with an high risk for moderate renal function loss, we aimed to assess the renal function adaptation over a long period of time in children with unilateral renal tumor (URT). PROCEDURE: Seventy-two children who underwent surgery for URT were enrolled in this study. Glomerular filtration rate was estimated (eGFR) with the Modification of Diet in Renal Study or the Schwartz equation, as appropriate for the age. RESULTS: Twelve patients treated by nephron-sparing surgery (Group A) and 42 treated by nephrectomy (Group B) had an age between 2 and 30 years; 18 patients treated by nephrectomy had an age between 33 and 51 years (Group C). At cross-sectional follow-up 8% patients of Group A, 42% of Group B and 78% of Group C presented a mild-to-moderate renal function. The longitudinal data stratified by post-operative intervals showed that patients of Group C presented a significant progressive decrease in mean ± standard deviation eGFR (88.1 ± 22.6 during the third decade after surgery vs. 66.6 ± 15.6 ml/min/1.73 m(2) during the fifth decade after surgery; P = 0.02). The longitudinal data stratified by age showed that patients with an age between 45 and 54 years presented a mean eGFR significantly lower than that expected for the physiological renal function decline with aging (P = 0.001). CONCLUSION: Aging is associated with a mild-to-moderate renal function loss in many adult patients following nephrectomy during childhood for URT.

The use of Tachosil as hemostatic sealant in nephron sparing surgery for Wilms tumor: preliminary observations.

BACKGROUND: TachoSil, which is an absorbable collagen sponge coated with human fibrinogen and thrombin, has proven to enhance hemostasis and promote optimal wound healing in adults undergoing nephron sparing surgery (NSS). We report our preliminary experience using this hemostatic agent during NSS in children. METHODS: Prospective analysis of 3 patients with Wilms tumor (synchronous bilateral in one) undergoing NSS at our institution over an 18-month period. Primary outcome measures were intraoperative bleeding control and surgery-related postoperative sequelae. RESULTS: Overall, 4 kidneys underwent 5 NSS procedures, which included 3 partial nephrectomies and multiple tumor excisions performed on another kidney at initial and second-look surgery. After control of major bleeding and suturing of the collecting system, which was entered during 2 of the 5 NSS procedures, TachoSil was applied to the parenchymal surface of the kidney, achieving immediate hemostasis. All NSS procedures were performed without hilar clamping, drainage or stent placement. None of the patients required blood transfusion. Small perirenal fluid collections were documented postoperatively, and all spontaneously resolved within 4 weeks of surgery. CONCLUSION: In children undergoing NSS, TachoSil represents an effective and safe tool for control of mild to moderate bleeding, and also facilitates sealing and wound dressing.

Long-term follow-up of the "wait and see" approach to localized perinatal adrenal neuroblastoma.

BACKGROUND: Evidence-based guidelines for the management of localized perinatal adrenal neuroblastoma are not yet available. We describe our preliminary experience managing this tumor with a "wait and see" policy. METHODS: A single-center prospective study (February 2002 to December 2009) was conducted with 12 consecutive patients in whom an adrenal mass was detected antenatally or within the first 3 months of life. Diagnostic workup included the following investigations: measurement of urine catecholamine metabolites, imaging studies (ultrasonography, magnetic resonance imaging, or computed tomography), metaiodobenzylguanidine scintigraphy, and/or core needle biopsy. RESULTS: The male/female ratio was 1.4:1.0. Median tumor size at presentation was 29 mm (range 10-50 mm). Eight lesions were detected antenatally. Ten lesions were diagnosed as localized neuroblastoma. Of these ten lesions, four were excised because of parental preference (n = 2), tumor enlargement (n = 1) or tumor persistence (n = 1). The remaining six patients underwent watchful clinical observation, which showed progressive tumor shrinkage and complete regression within 10-39 months (median 12.5 months). The final two lesions were small predominantly cystic lesions without a clear-cut diagnosis. They were managed noninvasively. At an overall median follow-up of 109 months (range 30-122 months), all patients are alive and disease-free, although one patient progressed to stage 4 disease despite early excision of the primary tumor. CONCLUSIONS: Spontaneous regression of localized perinatal adrenal neuroblastoma occurs often, and a "wait and see" strategy seems justified in these small infants. Patients with enlarging or stable lesions that have persisted for several months may benefit from surgery, although prompt excision may not prevent tumor progression.

Laparoscopic pyloroplasty for idiopathic non-hypertrophic pyloric stenosis in a child.

Acquired gastric outlet obstruction (GOO) during infancy and childhood represents an uncommon event. We describe a 6-year-old boy with GOO who did not respond to medical treatment or to endoscopic pyloric balloon dilatations. The stenosis was successfully treated with laparoscopic pyloroplasty which relieved the obstruction.

Intrahepatic paratesticular cyst: unique presentation of vestigial remnants of Wolffian duct.

To report on a case of a progressively enlarging intrahepatic cyst in a 1-year-old boy who also presented with bilateral undescended testes. At surgery, the lesion emerged from the anterior surface of the liver but was unexpectedly found to arise from the epididymis of the right testis, which was located intra-abdominally. The histologic findings were consistent with a paratesticular cyst of vestigial remnants derived from the Wolffian duct. Such an unusual event has not been previously reported among the possible location of a paratesticular cyst, nor has it been described in the differential diagnosis of cystic lesions of the liver.

Severe primary obstructive megaureter in the first year of life: preliminary experience with endoscopic balloon dilation.

BACKGROUND AND PURPOSE: Although conservative management is indicated in most cases of primary obstructed megaureter (POM), surgery is still indicated when POM is associated with increasing dilation, symptoms, or progressive renal damage. Surgery is associated with a significant rate of complications, however, especially in the case of very large ureter in the first year of life. A valid alternative could be endoscopic high pressure balloon dilation (EHPBD) of the vesicoureteral junction (VUJ). We report the first experience with EHPBD in patients under 1 year of age who were affected by severe POM. PATIENTS AND METHODS: Five patients, aged between 6 and 12 months, were treated with EHPBD. In all patients, preoperative renal ultrasonography showed a distal ureteral dilation ≥15 mm that increased at later evaluations; an obstructive pattern was detected by preoperative diuretic renography. An 8-9,8 F cystoscope, and a 3F balloon catheter (balloon maximum diameter 4 mm) was used. The VUJ was dilated for 5 minutes at 12 to 14 atm. A 4.7F Double-J stent was then positioned and left in place for 6 to 8 weeks. Ultrasonography was performed every 3 months, and renography and voiding cystourethrography the fourth month after the EHPBD. RESULTS: No operative complications were observed. All the patients showed an improvement at the ultrasonography postoperative follow-up, and there was no evidence of obstruction/reflux at the postoperative check up. CONCLUSIONS: Our preliminary results seem to indicate that EHPBD is a feasible, safe, and successful procedure. It could play a role as a minimally invasive alternative to open surgery in cases of POM that necessitate intervention in the first year of life. Longer follow-up is necessary to verify the stability of these results.

Stepladder incision technique for radical excision of suprasternal thyroglossal duct remnant.

Thyroglossal duct remnant localized to the suprasternal notch is an exceedingly rare condition. We report on a novel case occurring in an 8-year-old girl who presented with acute onset of a suprasternal abscess. After incision and drainage, a Sistrunk procedure was successfully carried out using 2 stepladder incisions. This approach combined optimal surgical exposure and satisfactory cosmesis.

Posterior urethral valves: relationship between vesicoureteral reflux and renal function.

OBJECTIVE: To investigate the relationship between renal function and vesicoureteral reflux before and after valve ablation in patients with posterior urethral valves. In these patients, back pressure may not be the only cause of renal damage. MATERIAL AND METHODS: We conducted a retrospective review of 37 patients with valves consecutively treated between 1970 and 2002. Data were available for 31 patients, 19 of whom presented reflux at presentation. Grade of reflux was ascertained by voiding cystourethrography. Overall renal function was measured by serum creatinine, and split renal function was estimated by dimercaptosuccinic acid scan available for all patients but two. RESULTS: Before relief of obstruction, there was no correlation between split renal function and grade of reflux into 25 kidneys of the 17 patients (r = -.13; 95% CI, -.50 to .27; P = .51). High-grade reflux (grade IV-V) affected 6 of the 11 renal units, with split renal function >40% vs 11 of the 14 units with split renal function <40% (P = .38). After successful valve ablation, reflux resolved in all the 11 units with split renal function >40% vs 4 of the 14 units with split renal function <40% (P = .0005). CONCLUSION: The good renal function of more than half of the renal units with high-grade reflux at presentation, and the persistence of reflux mainly in nonfunctioning or poorly functioning kidneys after valve ablation, support the concept that in some patients with valves, reflux and renal damage are associated anomalies.