Initial observational management of hydronephrosis in infants with reduced differential renal function and non-obstructive drainage parameters.

INTRODUCTION: Hydronephrosis secondary to ureteropelvic junction (UPJ) obstruction is a common finding in infants with prenatally-diagnosed hydronephrosis and often results in pyeloplasty due to obstructive drainage parameters and/or renal function compromise. However, little is known regarding the natural history of hydronephrosis with reduced differential renal function (DRF) but non-obstructive drainage. OBJECTIVE: We sought to explore our experience with initial observational management of these patients. STUDY DESIGN: A retrospective review of our institutional database of all diuretic MAG-3 renal scans obtained between 2000 and 2016 was performed. We included patients with antenatally-detected unilateral hydronephrosis ≥ SFU grade 2, first MAG-3 scan prior to 18months of age, DRF <40% and post-furosemide half-time (T1/2) <20 min. Exclusion criteria were: hydroureter, VUR, solitary kidney, duplication anomalies. Outcomes of interest were a progression of T1/2 ≥ 20 min and/or further decline in DRF >5%. RESULTS: Of 704 patients with unilateral hydronephrosis, 91 had DRF≤40%, of which 29 (18 boys, 11 girls) met our inclusion criteria and were followed for a mean of 2.8 years (1.4 months-6.6 years). Mean age at first sonogram was 2.3 months. 2 patients had SFU grade 2, 16 had grade 3, and 9 had grade 4 hydronephrosis, and 2 unknown grade. Median half-time on initial MAG-3 scan across all patients was 10 min (3-20 min). Initial MAG3 scan was performed at a median of 2.3 months of age (0.3-17 months). 22/29 patients had >1 MAG3 scan. Of the 7 remaining, 5 were lost to follow-up and 2 demonstrated improvement in hydronephrosis. Worsening drainage occurred in 10/22(45%), median final T1/2 was 45.5 min 8 of these underwent pyeloplasty and 2 were lost to follow up. 4/22 patients (18%) had progressive decline in DRF (mean 8.3%, range 6-10%). 3/4 maintained non-obstructive drainage patterns and stable/improved hydronephrosis, and 1 underwent pyeloplasty. 13/18 remaining patients had stable DRF and 5 had improvement in DRF. 7(39%) of these underwent surgery for worsening drainage (Summary Figure). Overall, 7/29(24%) patients had sufficient resolution of hydronephrosis to be discharged from our care, 8(28%) are under continued observation, 9(31%) underwent pyeloplasty, and 5(17%) were lost to follow-up. In the observational group [median follow-up 4.5 years (3.7-6.6 years)], all 8 demonstrated improved non-obstructive drainage (T1/2 <20 minutes) and/or improvement in hydronephrosis. 4/10(40%) with DRF <35% underwent pyeloplasty versus 5/19(26%) with DRF 35-40%(p=0.67). CONCLUSION: Initial observational management of unilateral hydronephrosis with reduced DRF and nonobstructive drainage is recommended as most kidneys maintain nonobstructive drainage and do not demonstrate further decline in DRF. Even when DRF decreases, the majority remain non-obstructive. Worsening drainage over time more often leads to the decision for pyeloplasty rather than change in DRF.

Impact of COVID-19 pandemic on the presentation, management and outcome of testicular torsion in the pediatric population - an analysis of a large pediatric center.

INTRODUCTION To examine the impact of COVID-19 pandemic on the presentation, management and outcome of testicular torsion at our institution. MATERIALS AND METHODS: A retrospective review of a prospectively maintained testicular torsion database was performed. Patients ≤ 18 years of age evaluated in our emergency room between 3/11/2020 to 10/1/2020 (during-COVID-19) and the same period in 2018 and 2019 (pre-COVID-19) with US diagnosed and OR confirmed testicular torsion were included. Basic demographics, timing of presentation, referral rate, time to OR and orchiectomy rate were extracted and compared. P < 0.05 was considered statistically significant. RESULTS: A total of 82 torsions were included in the study; 55 pre-COVID-19 and 27 during-COVID-19. The incidence of testicular torsion remained the same; 3.93 cases/month pre-COVID-19 versus 3.86 cases/month during-COVID-19 (p = 0.791). However, there were significantly fewer delayed (> 24 hours) presentations (11.1% versus 45.5% , p = 0.003), shorter time from onset of symptoms to presentation (median 15.5 hours versus 8 hours, p = 0.001), and a lower but not statistically significant overall orchiectomy rate (33.3% versus 50.9% p = 0.1608) during-COVID-19. Among those presenting acutely with torsion (< 24 hours from onset), no statistical differences were found in the median time from US diagnosis to OR, from ED to OR, referral rate, or orchiectomy rate between the two groups. Lastly, SARS-CoV2 testing did not delay median time from ED to OR. CONCLUSIONS: There was a notably less delayed presentation of testicular torsion and shorter ischemia time on presentation during-COVID, however, no significant change of time to OR or orchiectomy rate in those with acute testicular torsion were observed.

High incidence of abnormal imaging findings in circumcised boys diagnosed with urinary tract infections.

BACKGROUND: The American Academy of Pediatrics guidelines recommend delaying voiding cystourethrogram (VCUG) until the second febrile urinary tract infection (UTI). Similarly, the NICE Guidelines do not recommend VCUG after the first febrile UTI in infants and children under three years of age. Currently, there is no good clinical indicator to determine which patients would benefit from an earlier cystogram. Here, we sought to identify clinical and bacteriologic findings that are associated with an increased risk of urinary tract anatomic anomalies in pediatric males presenting to the Emergency Department with a UTI. METHODS: A retrospective review was performed of all urine cultures from the Emergency Department at our institution between 2006 and 2015. Males under 18 years of age with ≥50,000 CFU/mL of Proteus, Klebsiella, Escherichia coli, Staphylococcus, Streptococcus and Enterococcus were included. Clean catch, catheterized and suprapubic aspiration specimens were included. Bagged specimens and specimens from patients on intermittent catheterization were excluded. Ultrasound and cystogram images were reviewed when available. Univariate and multivariable Poisson regression with robust variance was used to calculate and compare prevalence ratios. Statistical analysis was performed with Stata software, version 15.1 MP (Stata Corporation, College Station, Texas, USA). RESULTS: We reviewed 1585 urine cultures, of which 812 met eligibility criteria including 619 (76.2%) E. coli, 84 (10.3%) Proteus, 55 (6.8%) Klebsiella, 29 (3.6%) Staphylococcus, 13 (1.6%) Enterococcus and 12 (1.5%) Streptococcus. Median age was six months (2.4-36 months IQR). After adjusting for age, ethnicity and bacterial species, the prevalence of dilating vesicoureteral reflux (VUR, defined as grades III-V) was 5.3 times higher in circumcised males compared to uncircumcised males (95% CI: 2.4-11.4, p = 0.001). Circumcised males had a 3.1 times increased prevalence of high-grade hydronephrosis (defined as SFU grades 3 and 4) compared to uncircumcised males (prevalence ratio: 3.1, 95% CI: 1.0-10.0, p = 0.05). Among bacterial pathogens, no patients with Proteus UTI had high-grade hydronephrosis or dilating VUR. In contrast, Staphylococcal infections were associated significantly with dilating VUR (prevalence ratio 10.1, 95% CI: 2.3, 44.8; p = 0.002) and high-grade hydronephrosis (prevalence ratio 8.1, 95% CI: 1.7, 39.7; p = 0.010). CONCLUSIONS: Circumcision status is an independent predictor of structural urinary anomalies of the bladder and upper tracts in pediatric males with UTI, therefore circumcised males should be considered for early imaging, including VCUG, after their first UTI. Furthermore, Staphylococcal infections were associated with an even higher prevalence of high-grade hydronephrosis and dilating VUR and therefore warrant early investigation with VCUG. In contrast, none of the Proteus infections, which were seen almost exclusively in uncircumcised males, were associated with dilating VUR or hydronephrosis, making initial observation more appropriate in these patients.

Discrepant Rates of Hypospadias Surgical Complications: A Comparison of U.S. News & World Report and Pediatric Health Information System® Data and Published Literature.

PURPOSE: Complication rates of 5% to 10% and 12% to 23% have been observed following distal and proximal hypospadias repair, respectively. However, these rates may be overreported. We hypothesized that data from the Pediatric Health Information System would corroborate the complication rates reported in the literature and refute the rates established by U.S. News & World Report as quality metrics. MATERIALS AND METHODS: The Pediatric Health Information System database was interrogated for hypospadias and revision CPT® codes. To evaluate the appropriateness of the U.S. News & World Report code list to identify revisions, 3 CPT groups were defined. Group A included codes sought by U.S. News & World Report, group B included group A plus codes for acquired urethrocutaneous fistula in males and group C included group B plus any revision codes associated with the index procedures. To evaluate the appropriateness of U.S. News & World Report followup interval, we assessed revision rates with ever increasing followup intervals out to 7 years. Yearly revision rates were summarized by median and quantile to correlate whether median revision rates changed significantly depending on whether increased followup or enhanced code lists were used. RESULTS: Average complication rates for group A were 3.32% (range 0.48% to 7.36%) and 12.29% (3.48% to 36.36%) for distal and proximal repairs, respectively. Revision rates increased significantly from group A (median 3.32%) by inclusion of a more expansive list of CPT codes associated with revision procedures (group B, 4.26%, p <0.001 and group C, 6.37%, p <0.001) in distal hypospadias. Among proximal hypospadias cases this difference was not significant when comparing group A (12.29%) to group B (12.53%, p=0.813), but was significant when comparing group A to group C (22.14%, p <0.001). Median revision rates for distal and proximal hypospadias increased with longer followup for all 3 groups, although the upward trend was not statistically significant. CONCLUSIONS: Depending on how one defines hypospadias revision, no hospital within the Pediatric Health Information System data set meets the U.S. News & World Report definition of perfection, a finding that is supported by recent reports from some of the largest, most prolific and most highly regarded pediatric urology programs. We posit that the U.S. News & World Report quality metrics do not accurately reflect the nature of hypospadias surgery complication rates.

In pursuit of the perfect penis: Hypospadias repair outcomes.

Hypospadias is commonly assessed and repaired by pediatric urologists. Mild, distal hypospadias is generally more a cosmetic problem than a functional one and is more frequently encountered than severe, proximal hypospadias. Outcomes following repair, especially of mild phenotypes, are important to understand, but range widely in timing and measurability. Surgical complications, postoperative satisfaction of parents, patients, surgeons and even lay observers, urinary function, sexual function, and quality of life all may be considered as relevant outcomes of hypospadias repair. Existing studies examining these outcomes are diverse in their conclusions, but are important to understand when counseling parents and patients prior to any surgical intervention.

Prediction of Clinical Outcomes in Prenatal Hydronephrosis: Importance of Gravity Assisted Drainage.

PURPOSE: In infants with SFU (Society for Fetal Urology) grade 3-4 congenital hydronephrosis, 99mTc-mercaptoacetyltriglycine diuretic renography assesses differential function and drainage half-time. We routinely also include the percent of radiotracer drained after 30 minutes of diuresis as well as after 15 minutes with the patient in the upright position. We investigated whether any 1 or more of these parameters on initial diuretic renography predicts persistent or worsening drainage parameters. MATERIALS AND METHODS: Infants 6 months or younger with grade 3-4 congenital hydronephrosis who presented between January 2009 and December 2014 were identified from billing data and included in analysis if they underwent at least 1 baseline diuretic renography. Those with structural anomalies were excluded from study. Baseline and followup differential function, diuresis half-time, clearance at 30 minutes and clearance with the patient upright were abstracted and comparisons were made between those with initially indeterminate diuresis half-time who underwent pyeloplasty vs those showing spontaneous improvement. RESULTS: A total of 74 patients (82 renal units) with presumed ureteropelvic junction obstruction met inclusion/exclusion criteria. All 10 renal units with initial diuresis half-time less than 5 minutes resolved spontaneously and all 25 renal units with initial diuresis half-time greater than 75 minutes underwent pyeloplasty. Therefore, we defined the indeterminate group as the 47 renal units with initial half-time between 5 and 75 minutes. Of those 47 renal units with indeterminate initial diuresis half-time 23 (47%) underwent pyeloplasty and 25 (53%) resolved spontaneously. Indications for pyeloplasty included worsening in 17 cases, persistent obstruction in 4 and urinary tract infection in 1. Among renal units with indeterminate drainage clearance while upright and clearance at 30 minutes were the only variables that differed significantly between surgical cases and those that resolved spontaneously. CONCLUSIONS: Radiotracer clearance with the patient upright and clearance at 30 minutes are more predictive of surgical management than diuresis half-time or differential function for renal units with indeterminate drainage. They should be included in the standard assessment of ureteropelvic junction obstruction.

Vesicoureteral Reflux and Antibiotic Prophylaxis: Why Cohorts and Methodologies Matter.

PURPOSE: Published cohorts of children with vesicoureteral reflux placed on antibiotic prophylaxis differ in baseline characteristics and methodology. These data have been combined in meta-analyses to derive treatment recommendations. We analyzed these cohorts in an attempt to understand the disparate outcomes reported. MATERIALS AND METHODS: A total of 18 studies were identified from 1987 to 2013. These series retrospectively or prospectively evaluated children with vesicoureteral reflux who were on long-term antibiotic prophylaxis. Presenting demographic data, criteria and methods of evaluation were tabulated. Outcomes were compared, specifically recurrent urinary infections and renal scarring. RESULTS: Significant differences identified in baseline characteristics included gender, circumcision status and reflux grade, and differences in methodology included evaluation of bowel and bladder dysfunction, method of urine collection, definition of urinary infection, measurement of compliance and means of identifying renal scarring. Cohorts with larger numbers of uncircumcised boys had more breakthrough urinary infections. Infection and renal scarring rates were higher in series with higher grades of reflux. Bagged urine specimens were allowed in 6 series, rendering the data suspect. Children with bowel and bladder dysfunction were excluded from 3 cohorts, and bowel and bladder dysfunction was correlated with outcome in only 1 cohort. Compliance was monitored in only 6 studies. CONCLUSIONS: Subpopulations and methodologies vary significantly in published series of children with vesicoureteral reflux on antibiotic prophylaxis. It is inappropriate to combine outcomes data from these series in a meta-analysis, which would serve to blur distinctions between these subpopulations. Broad recommendations or guidelines based on meta-analyses should be viewed with caution.

Risk Factors for Catheter Associated Urinary Tract Infections in a Pediatric Institution.

PURPOSE: Catheter associated urinary tract infections are an essential measure for health care quality improvement that affects reimbursement through hospital acquired condition reduction programs in adult patients. With the mounting importance of preventing such infections we evaluated risk factors for acquiring catheter associated urinary tract infections in pediatric patients. MATERIALS AND METHODS: All catheter associated urinary tract infections were identified at 1 pediatric institution from September 2010 to August 2014 from a prospective database maintained by the infection control office. To identify risk factors patients with a catheter associated urinary tract infection were individually matched to control patients with a urinary catheter but without infection by age, gender, date and the hospital location of the infection in 1:2 fashion. RESULTS: A total of 50 patients with catheter associated urinary tract infection were identified and matched to 100 control patients. Compared to controls the patients with infection were more likely to have a catheter in place for longer (2.9 days, OR 1.08, 95% CI 1.01, 1.15, p = 0.02). They were also more likely to be on contact precautions (OR 4.00, 95% CI 1.73, 9.26, p = 0.001), and have concurrent infections (OR 3.04, 95% CI 1.39, 6.28, p = 0.005) and a history of catheterization (OR 3.24, 95% CI 1.55, 6.77, p = 0.002). Using a conditional multivariate regression model the 3 most predictive variables were duration of catheter drainage, contact isolation status and history of catheterization. CONCLUSIONS: Longer duration of urinary catheter drainage, positive contact precautions status and a history of catheterization appear to be associated with a higher risk of catheter associated urinary tract infection in hospitalized pediatric patients. Physicians should attempt to decrease the duration of catheterization, especially in patients who meet these criteria, to minimize the risk of catheter associated urinary tract infection.

The "flowerpot" sign: inference of poor renal function in high grade vesicoureteral reflux by calyceal orientation.

INTRODUCTION/OBJECTIVE: Modern radiographic advances have allowed for detailed and accurate imaging of not only urologic anatomy but also urologic function. The art of observational inference of subtle anatomic features and function from a static radiograph is being traded for new, more precise, and more expensive modalities. While the superiority of these methods cannot be denied, the total information provided in simpler tests should not be ignored. The relationship between high grade vesicoureteral reflux with the dilated calyces arranged cephalad to a dilated funnel-shaped renal pelvis on VCUG and reduced differential renal function has not been previously described, but has been anecdotally designated a "flowerpot" sign by our clinicians. We hypothesize that the appearance of a "flowerpot" kidney as described herein is an indicator of poor renal function in the setting of high grade VUR. STUDY DESIGN: IRB approval was obtained and 315 patients were identified from system-wide VCUG reports from 2004-2012 with diagnosed "high grade" or "severe" vesicoureteral reflux. Inclusion into the study required grade IV or V VUR on initial VCUG and an initial radionuclide study for determination of differential function. Patients with a solitary kidney, posterior urethral valve, multicystic dysplastic kidney, renal ectopia, or duplex collecting systems were excluded. Grade of reflux, angle of the inferior-superior calyceal axis relative to the lumbar spine, and differential uptake were recorded along with presence of the new "flowerpot" sign. Variables were analyzed using the Mann-Whitney U test to determine statistical significance. RESULTS: Fifty seven patients met inclusion criteria with 11 being designated as "flowerpot" kidneys. These "flowerpot" kidneys could be objectively differentiated from other kidneys with grade IV and/or grade V VUR both by inferior-superior calyceal axis (median angle, 52° [37-66] vs. 13° [2-37], respectively p < 0.001) and by differential renal uptake (median, 23% [5-49] vs. 45% [15-81], respectively p < 0.001). Likewise, there was no difference between either calyceal axis (median angle, 13° [3-20] vs. 13° [2-37]) or differential function (median, 48% [24-81] vs. 40% [15-66], p = 0.129) when comparing kidneys with grade IV and grade V VUR, respectively, that did not demonstrate the "flowerpot" sign. DISCUSSION/CONCLUSION: Grading of VUR is used to provide a common language for scientific discussion and determine prognosis for children with similar attributes. The dysmorphic calyceal system in the "flowerpot" kidneys supports the theory of abnormal renal blastema induction associated with abnormal differentiation of the ureteral bud. Even in the absence of urinary tract infections and/or pyelonephritis, renal abnormalities and decreased differential function can be observed on renal scintigraphy. This study also confirms the male predominance and functional similarities between grade 4 and 5 refluxing renal units. Recognizing this is a limited observational study based on imaging alone, the "flowerpot" sign is an indicator of the most severe form of grade 5 VUR but is only one factor in predicting long term overall renal prognosis. However, 14% (8/57) of our cohort had a relative uptake of less than 20% with 5 of these exhibiting the "flowerpot" sign. The "flowerpot" sign on VCUG can be used as indirect evidence of poor differential renal function and, therefore, useful in guiding parental expectations prior to formal functional imaging.

Evaluation of prenatal hydronephrosis: novel criteria for predicting vesicoureteral reflux on ultrasonography.

PURPOSE: Radiographic evaluation for prenatal hydronephrosis often includes voiding cystourethrography to ascertain whether vesicoureteral reflux is present. We sought to determine whether use of voiding cystourethrography could be limited to those patients at greatest risk for vesicoureteral reflux. We hypothesized that vesicoureteral reflux could be predicted by findings on renal/bladder ultrasonography of hydroureter, renal dysmorphia and/or duplication. MATERIALS AND METHODS: We reviewed the records of patients with prenatal hydronephrosis who underwent initial postnatal ultrasonography and voiding cystourethrography during a 3-year period. The presence of vesicoureteral reflux on voiding cystourethrogram was correlated to ultrasound findings, including hydronephrosis grade, presence of hydroureter, renal dysmorphia or duplication, with ultrasound considered positive for any of the latter 3 findings. RESULTS: Of 262 patients 47 (18%) had vesicoureteral reflux. Ultrasound was positive in 24 of 29 patients (83%) with high grade reflux and 12 of 18 (67%) with low grade reflux. If ultrasonography showed any of the 3 positive findings, the odds ratio of detecting vesicoureteral reflux was 8.07 (95% CI 3.86, 16.87). Using these criteria, among all cases of prenatal hydronephrosis 5 (2%) with high grade vesicoureteral reflux and 6 (2%) with low grade reflux would have been missed. Among the 47 cases of reflux overall 5 of 29 high grade (17%) and 6 of 18 low grade cases (33%) would have been missed. CONCLUSIONS: By using ultrasonography criteria of hydroureter, duplication and renal dysmorphia for patients with prenatal hydronephrosis, vesicoureteral reflux can be detected more specifically. Using our criteria, 165 of 262 voiding cystourethrograms (63%) could have been avoided in patients with prenatal hydronephrosis during a 3-year period. Reducing these evaluations may decrease risks regarding radiation exposure, family anxiety and health care costs.

The prevalence of bell clapper anomaly in the solitary testis in cases of prior perinatal torsion.

PURPOSE: Bell clapper anomaly is associated with an increased risk of intravaginal testicular torsion. However, perinatal torsion is thought to be secondary to an extravaginal process. We quantified the contralateral prevalence of bell clapper anomaly in children found to have atrophic testicular nubbins secondary to presumed torsion during gestation to better define the subsequent risk of metachronous testicular torsion. MATERIALS AND METHODS: Inspection results for the presence of contralateral bell clapper anomaly was recorded by a single surgeon in 50 consecutive cases in which exploration for nonpalpable testes revealed a testicular nubbin. For comparison data were collected in 27 consecutive cases of acute testicular torsion. Anatomy of the normal contralateral testis was compared between the 2 groups. RESULTS: Average age at surgery in the perinatal torsion group was 15 months vs 12.7 years in the acute torsion group. One case of partial contralateral bell clapper anomaly was discovered in the perinatal torsion group but no complete anomaly was found. In contrast, in older boys with acute testicular torsion complete bell clapper anomaly was found in 21 of the 27 contralateral testes (78%). CONCLUSIONS: In older boys with acute testicular torsion contralateral bell clapper anomaly is highly prevalent, supporting the standard practice of contralateral testicular fixation in this clinical situation. However, the prevalence of contralateral bell clapper anomaly is exceedingly small in cases of monorchism after perinatal torsion, substantiating an insufficient risk of subsequent torsion to justify routine fixation of the solitary testis.

Most infants with dilating vesicoureteral reflux can be treated nonoperatively.

PURPOSE: Dilating vesicoureteral reflux provokes concern for physicians and parents that often leads to corrective surgery in young children. Since there are limited data describing the natural history of dilating vesicoureteral reflux in infants, we identified factors predictive of resolution/improvement in infants initially treated nonoperatively. MATERIALS AND METHODS: We reviewed the medical records of 90 infants 6 months old or younger from 2004 to 2010 who were referred for prenatal hydronephrosis or initial febrile urinary tract infection and found to have dilating vesicoureteral reflux (grade 3 or greater). Variables of interest included presentation, dimercapto-succinic acid results, sex, breakthrough febrile urinary tract infections, reflux grade and bilateral reflux. Cox regression analysis was performed to determine predictors of spontaneous resolution and/or improvement to reflux grade less than 3 as well as predictors of surgical intervention. RESULTS: Included in final analysis were 80 infants (113 renal units). Of the patients 51 (64%) experienced spontaneous resolution/improvement with a mean followup of 29 months before resolution, discharge home and/or end of followup. Only 20 patients (25%) underwent surgery. Cox regression analysis revealed that a normal initial dimercapto-succinic acid scan, initial reflux grade less than 5 and absent breakthrough febrile urinary tract infections were predictive of reflux resolution/improvement (p <0.05). Dimercapto-succinic acid scan abnormalities, prenatal hydronephrosis and breakthrough febrile urinary tract infections were significant predictors of surgery (p <0.05). CONCLUSIONS: Dilating vesicoureteral reflux in infancy often resolves/improves spontaneously. Therefore, surgery should be directed toward patients unlikely to experience resolution, ie those with an abnormal initial dimercapto-succinic acid scan, grade 5 vesicoureteral reflux and breakthrough febrile urinary tract infections.

Evaluation of differential renal function and renographic patterns in patients with dietl crisis.

PURPOSE: We analyzed preoperative and postoperative differential renal function and characterized the renographic findings in patients with ureteropelvic junction obstruction associated with Dietl crisis. MATERIALS AND METHODS: Patients with Dietl crisis who underwent pyeloplasty between January 2004 and December 2010 were classified by renographic presentation. Patients in group 1 were diagnosed with cortical retention, those in group 2 had an initial obstructed scan (T1/2 of 20 minutes or more and no cortical retention) and those in group 3 had an initial nondiagnostic scan (T1/2 of less than 20 minutes and no cortical retention). Renographic parameters were used to analyze each group. RESULTS: A total of 59 patients met criteria for study inclusion. The 13 patients in group 1 demonstrated the most significant recovery of function after pyeloplasty (mean differential renal function change 13.59%). The 38 patients in group 2 exhibited a mean differential renal function change of 43.06% (range 20% to 54.6%) and mean preoperative T1/2 of 64.31 minutes. Pyeloplasty was performed in all 8 patients in group 3 based on subsequent diagnostic scan (4 patients) or increased hydronephrosis on other imaging associated with further symptomatic episodes (4). Initial renographic patterns noted in group 3 included biphasic curves, diminished clearance after 15 minutes upright or symptoms despite nonobstructive drainage. CONCLUSIONS: Interpretation of diuretic renography requires the assimilation of multiple parameters since patients with Dietl crisis can exhibit variability in renographic patterns due to the intermittent nature of ureteropelvic junction obstruction. Cortical retention represents a specific and pathognomic finding of acute ureteropelvic junction obstruction. With appropriate evaluation of these parameters, obstruction can be reliably diagnosed and appropriate surgical candidates chosen.

Vesicoureteral reflux: current trends in diagnosis, screening, and treatment.

CONTEXT: Vesicoureteral reflux (VUR) is present in approximately 1% of children in North America and Europe and is associated with an increased risk of pyelonephritis and renal scarring. Despite its prevalence and potential morbidity, however, many aspects of VUR management are controversial. OBJECTIVE: Review the evidence surrounding current controversies in VUR diagnosis, screening, and treatment. EVIDENCE ACQUISITION: A systematic review was performed of Medline, Embase, Prospero, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, clinicaltrials.gov, and the most recent guidelines of relevant medical specialty organizations. EVIDENCE SYNTHESIS: We objectively assessed and summarized the published data, focusing on recent areas of controversy relating to VUR screening, diagnosis, and treatment. CONCLUSIONS: The evidence base for many current management patterns in VUR is limited. Areas that could significantly benefit from additional future research include improved identification of children who are at risk for VUR-related renal morbidity, improved stratification tools for determining which children would benefit most from which VUR treatment option, and improved reporting of long-term outcomes of VUR treatments.