Salvage Surgery Rates for Pediatric Testicular Torsion: Comparison of the Pre- and Post-Quality Metric Eras.

PURPOSE: Pediatric testicular torsion is a urological emergency that requires timely intervention. In 2015, quality metrics for testicular torsion were implemented in the U.S. News & World Report "Best Children's Hospitals" rankings. Our study examines and compares testicular salvage surgery rates before and after the institution of national quality metrics from a multi-institutional database. MATERIALS AND METHODS: The Pediatric Health Information System® was surveyed for all testicular torsion encounters using ICD (International Classification of Diseases), Ninth and Tenth Revisions coding from 52 hospitals between January 2010 and December 2019. Patients <1 year and ≥18 years of age were excluded. Only hospitals that reported outcomes before and after quality scoring were included. Testicular salvage surgery was defined as patients having undergone orchiopexy without concomitant orchiectomy. Age, race, distance from hospital, household income and insurance status were compared. RESULTS: A total of 890 patients (551 pre-metric and 339 post-metric) from 38 hospitals were included. The testicular salvage surgery rate was 12.5% higher in the post-metric cohort (70.9% versus 58.4%). Hospital compliance to testicular torsion quality metrics increased from 62% in 2015 to 98% in 2019. Mean age, race, distance to hospital, household income, insurance status and use of ultrasound were not statistically different between pre- and post-metric cohorts. CONCLUSIONS: Since the implementation of quality metrics, salvage surgery rates for testicular torsion increased to 70.9%, an improvement of 12.5% when compared to pre-metric outcomes. Patient factors were similar between the 2 groups. Multi-institutional prospective data are needed to validate this database study and evaluate overall testicular salvage rate.

Discrepancies in Self-Reported and Actual Conflicts of Interest for Robotic Pediatric Urological Surgery.

PURPOSE: Transparency of conflicts of interest is essential when assessing publications that address the benefits of robotic surgery over traditional laparoscopic and open operations. We assessed discrepancies between self-reported and actual conflicts of interest as well as whether conflicts of interest are associated with favorable endorsement of robotic surgery. MATERIALS AND METHODS: We searched the Embase® and MEDLINE® databases for articles on robotic surgery within pediatric urology. We included English language articles published since 2013, when data in the Open Payments program (Centers for Medicare and Medicaid Services, Baltimore, Maryland) became available. For all United States based authors Open Payments was used to identify the total amount of financial payment received from Intuitive Surgical®. Chi-square test was used to assess the association between conflicts of interest and favorable endorsement of robotic surgery. RESULTS: A total of 191 articles were initially identified. After exclusion criteria were applied 107 articles remained (267 distinct authors). Of the articles 86 (80.4%) had at least 1 author with a history of payment from Intuitive Surgical, with 79 (91.9%) having at least 1 author who did not declare a conflict of interest despite history of payment. A total of 44 authors (16.5%) had a history of payment from Intuitive Surgical, with an average payment of $3,594.15. Articles with a first and/or last author with a history of payment were more likely to contain a favorable endorsement of robotic surgery compared to articles without a history of payment (85.1% vs 63.6%, p = 0.0124). CONCLUSIONS: Nondisclosure of conflict of interest with Intuitive Surgical is extremely common within pediatric urology. Steps to ensure accurate reporting of conflicts of interest are essential. There appears to be an association between a history of payment and favorable endorsement of robotic surgery.

Bowel preparation prior to reconstructive urologic surgery in pediatric myelomeningocele patients.

INTRODUCTION: Mechanical bowel preparation (MBP) has historically been the standard of care for patients undergoing reconstructive urologic surgery, including urinary diversion. To date, several studies have examined the role of mechanical bowel preparation in postoperative outcomes in pediatric patients undergoing augmentation cystoplasty. However, these patient populations have been heterogeneous in nature, with no studies dedicated to examining the role of MBP prior to reconstructive urologic surgery in pediatric patients with myelomenginoceles. Thus, our objective was to retrospectively assess perioperative measures and postoperative complications after reconstructive urologic surgery with or without mechanical bowel preparation in pediatric myelomeningocele patients. MATERIALS AND METHODS: From 2008 to 2013, 80 patients with myelomeningocele underwent reconstructive urologic surgery involving the use of bowel. Seventy patients underwent a preoperative MBP while 10 did not. Perioperative measures and postoperative complications for these two cohorts were assessed. RESULTS: Eighty patients with myelomeningocele were identified; 70 patients underwent MBP while 10 patients did not. There were no statistically significant differences in demographics or operative time. There were no statistically significant differences in postoperative outcomes including time to first bowel movement and time to tolerating diet. There was also no significant difference in overall complication rate; patients with MBP had 31/70 (44%) complications while 2/10 (20%) of those without MBP had complications (p = 0.18). CONCLUSION: There was no significant difference in perioperative measures and postoperative complications for patients who did not receive a mechanical bowel preparation. Our findings indicate that it is safe and warranted to perform a prospective, randomized study to better characterize the risks and benefits of preoperative bowel preparation for patients with myelomeningocele.

The Clavien-Dindo Classification of Surgical Complications is Not a Statistically Reliable System for Grading Morbidity in Pediatric Urology.

PURPOSE: Although the Clavien-Dindo classification of surgical complications has been evaluated using adult surgical patients, it is being applied to pediatric populations. We hypothesized that this instrument is not well suited to children and sought to determine the reliability of the tool in a pediatric urological population. MATERIALS AND METHODS: We replaced adult surgical cases in the "Survey to Assess Acceptability and Reproducibility of the Classification" from the original Clavien-Dindo study with pediatric urology cases and mimicked original study methods. The survey was distributed with the REDCap (Research Electronic Data Capture) tool, and Krippendorff α coefficients of reliability were calculated from the responses. RESULTS: There were 51 respondents and 40 complete responses. The Krippendorff α coefficient of reliability for the Clavien-Dindo classification (α = 0.487) did not achieve the minimum level of acceptable agreement (α = 0.667) with the pediatric urological cases, even when the disability suffix (α = 0.266) was excluded from the analysis (α = 0.632). The accuracy of the grading system with the pediatric urological surgical cases when excluding the disability suffix (410 of 550, 75%) was significantly less than the accuracy had been with the original adult cases (1,816 of 2,016, 90%, p <0.0001). While 89% of respondents (32 of 36) thought the system was appropriate for adults, only 49% (17 of 35) found it appropriate for children (p <0.001). CONCLUSIONS: The Clavien-Dindo classification of surgical complications is not a reliable tool for use in pediatric urology, where its accuracy is significantly decreased compared to adult surgical cases. Further study is needed to determine if findings are similar across all pediatric surgical groups.

24-Hour Urinary Parameters in Overweight and Obese Children with Urolithiasis.

PURPOSE: The increasing incidence of pediatric nephrolithiasis is a growing concern and its association with obesity continues to be an area of debate. We present data on urine chemistries of overweight/obese children compared to those with a normal body mass index and history of urolithiasis treated at a single institution in the United States, and assess risk factors. MATERIALS AND METHODS: We retrospectively identified 110 stone forming patients who underwent 24-hour urine collection and stratified them according to the Centers for Disease Control and Prevention definitions of overweight/obese (body mass index above 85th/95th percentile). Absolute urine collection quantities were compared between groups. Stone risk factors were analyzed according to Litholink® specified reference ranges. RESULTS: Compared to patients with low or normal body mass index, overweight and obese patients had lower body surface area adjusted citrate (242 mg/1.73 m(2) vs 315 mg/1.73 m(2), p = 0.03), lower urine phosphate (12 mg/kg vs 14 mg/kg, p = 0.04), lower urine magnesium (1.2 mg/kg vs 1.6 mg/kg, p = 0.01) and increased incidence of hypercalciuria (31% vs 11%, p = 0.02). Differences in urine citrate, phosphate and magnesium were not apparent when analyzing stone risk factors. There was no association between body mass index and urine pH. CONCLUSIONS: Overweight and obese stone forming children have decreased levels of urine citrate, phosphate and magnesium compared to patients with normal body mass index. The incidence of hypercalciuria is increased in overweight/obese patients. In contrast to findings in adults, there is no association between urine pH and body mass index.

Multi-institutional review of outcomes of robot-assisted laparoscopic extravesical ureteral reimplantation.

PURPOSE: We performed a multi-institutional assessment of the outcomes and complications of robot-assisted laparoscopic extravesical ureteral reimplantation for vesicoureteral reflux in children. MATERIALS AND METHODS: We retrospectively reviewed the records of patients who underwent robot-assisted laparoscopic extravesical ureteral reimplantation as done by 1 of 5 surgeons at Children's Medical Center, Dallas, Texas, or Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania, from 2010 to 2013. Procedure failure was defined as persistent vesicoureteral reflux on postoperative voiding cystourethrogram or radionuclide cystogram and/or the need for reoperation. Multivariate logistic regression was done to identify possible risk factors for failure using STATA®, version 11. RESULTS: A total of 61 patients (93 ureters) with a mean age of 6.7 years (range 0.6 to 18.0) underwent a procedure, of which 32 (52%) were bilateral. Ten patients (16%) underwent previous subureteral injection for vesicoureteral reflux. At a mean followup of 11.7 months the procedure was successful in 44 of 61 patients (72%). There were 14 cases of persistent vesicoureteral reflux (23%), 6 complications (10%) and 9 reoperations (11%). Multivariate logistic regression identified no factor that increased the risk of failure (p = 0.737). CONCLUSIONS: Compared to the literature we found a notably lower success rate for robot-assisted laparoscopic extravesical ureteral reimplantation in the hands of 5 fellowship trained, robotically experienced pediatric urologists. More than 10% of patients required at least 1 reoperation for persistent vesicoureteral reflux or a surgical complication. Our experience suggests a higher complication rate and a lower success rate for robot-assisted laparoscopic ureteral reimplantation compared to the gold standard of open reimplantation.

Timing and predictors for urinary drainage in children with expectantly managed grade IV renal trauma.

PURPOSE: We determined which children sustaining blunt grade IV renal trauma are at greatest risk for failing nonoperative management and in what time frame they will likely present. MATERIALS AND METHODS: We retrospectively reviewed children presenting with nonvascular grade IV blunt renal trauma between 2003 and 2012. We compared characteristics on computerized tomography, reasons for intervention, type and timing of surgery, length of hospital stay and need for readmission between children undergoing early intervention (less than 72 hours after admission) and those managed conservatively (with any subsequent intervention undertaken more than 72 hours after admission). RESULTS: A total of 26 children were identified with nonvascular grade IV blunt renal trauma. Conservative management was attempted in 16 cases (62%). Seven of these patients (44%) required intervention (ureteral stent and/or percutaneous drain placement), with a mean time to intervention of 11 days. Collecting system clot and larger urinoma (1.45 cm in cases with successful and 4.29 cm in those with failed conservative management) significantly predicted failure of conservative management (p<0.05). Presence of dissociated renal fragments (57% vs 11%) and interpolar contrast extravasation (57% vs 0%) were increased in the early intervention group compared to the conservatively managed group (p>0.05), as was rehospitalization (43% vs 0%), mean length of stay (7.9 vs 5.4 days) and transfusion (14% vs 0%, p>0.05). CONCLUSIONS: Collecting system hematoma and urinoma size significantly predicted failure of conservative management, with a mean time to intervention of 11 days. Children with failed conservative management had a greater incidence of dissociated renal fragments and interpolar extravasation. Early identification of these patients may decrease hospital readmissions, length of stay and prolonged morbidity.

Cystatin C as a marker of early renal insufficiency in children with congenital neuropathic bladder.

PURPOSE: Due to decreased muscle mass in children with congenital neuropathic bladder there may be significant inaccuracy when using the creatinine based estimated glomerular filtration rate. Cystatin C is highly sensitive and specific for measuring changes in the glomerular filtration rate in children and in patients with muscle wasting conditions. We hypothesized that a cystatin C calculated glomerular filtration rate would be more sensitive than the standard creatinine based modified Schwartz equation to detect renal insufficiency in children with congenital neuropathic bladder. MATERIALS AND METHODS: We prospectively identified children with congenital neuropathic bladder at a multidisciplinary spina bifida clinic who underwent serum creatinine and serum cystatin C testing. Clinical history and anthropomorphic variables at the time of laboratory testing were catalogued. The creatinine based glomerular filtration rate was estimated using the modified (bedside) Schwartz formula and the cystatin C based rate was calculated using the Zappitelli cystatin C formula. RESULTS: Dual estimated glomerular filtration rate calculation was done in 69 children at a total of 74 patient encounters. Absolute creatinine was within age range normal limits in each patient, including 1 with chronic kidney disease stage 3A. The median creatinine based estimated glomerular filtration rate was 123 ml per minute/1.73 m(2) (range 58 to 229). The median cystatin C based estimated rate was 103 ml per minute/1.73 m(2) (range 47 to 144) for an absolute median rate reduction of 15.4%. Using cystatin C estimates chronic kidney disease stage was upgraded from stage 1 to 2 in 13 patients (18.8%). CONCLUSIONS: In children with neuropathic bladder the cystatin C estimated glomerular filtration rate is a better screening test for early renal insufficiency that is not detected by creatinine based rate calculations. To our knowledge it remains to be determined whether the cystatin C estimated glomerular filtration rate can ultimately improve the clinical outcome in this population.

Cost analysis of pediatric robot-assisted and laparoscopic pyeloplasty.

PURPOSE: An increasing percentage of pediatric pyeloplasties are being performed with assistance of the da Vinci® Surgical System. A review of the recent literature shows decreased operative times and length of hospital stays when robotic procedures are performed, although there are few published data comparing the cost of pediatric robotic and pure laparoscopic pyeloplasty. We reviewed a representative sample of pyeloplasties performed at our institution and performed a cost analysis. MATERIALS AND METHODS: We retrospectively identified 23 robot-assisted and 23 laparoscopic pyeloplasties performed at our institution between August 2008 and April 2012. Total cost was calculated from direct and indirect costs provided by our billing department. RESULTS: Robotic procedures were shorter than pure laparoscopic procedures (200 vs 265 minutes, p <0.001) but there was no significant difference in the total cost of the 2 procedures ($15,337 vs $16,067, p <0.46). When compared to laparoscopic cases, subgroup analysis demonstrated decreased operative times (140 vs 265 minutes, p <0.00001) and total cost ($11,949 vs $16,067, p <0.0001) in robotic cases where stents were placed in an antegrade fashion. CONCLUSIONS: With widespread use the cost of robotic instrumentation may decrease, and experience may further shorten operative times. However, it currently remains to be seen whether robotic technology will become a cost-effective replacement for pure laparoscopy in the management of pediatric ureteropelvic junction obstruction.

Metanephric adenofibroma.

A 10-year-old boy underwent a computed tomography (CT) scan for left flank pain following a fall. Imaging demonstrated a 5 cm left upper pole renal mass. Partial nephrectomy revealed metanephric adenofibroma, a benign stromal-epithelial tumor thought to represent a hyperdifferentiated, mature form of Wilms' tumor. We briefly discuss the histopathology and management of this rare tumor.

Pyeloplasty with ureteral stent placement in children: Do prophylactic antibiotics serve a purpose?

OBJECTIVES: Ureteral stents are commonly used during pyeloplasty to ensure drainage and anastomotic healing. Antibiotic prophylaxis is often used due to concerns for urinary tract infection (UTI). Although many surgeons prescribe prophylactic antibiotics following pyeloplasty, practices vary widely due to lack of clear evidence-based guidelines. We hypothesize that the rate of stent UTI does not significantly vary between children who receive antibiotics and those who do not. METHODS: We reviewed the medical records of 741 patients undergoing pyeloplasty between January 2010 and July 2018 across seven institutions. Exclusion criteria were: age older than 22 years, no stent placed, externalized stents used, and incomplete records. Surgical approach, age, antibiotic use, stent duration, Foley duration, and urine culture results were recorded. Patients were categorized into two groups, those younger than four years of age and those four years and older as proxy for likely diaper use. Univariate logistic regression was conducted to identify variables associated with UTI. Multivariable backward stepwise logistic regression was used to identify the best model with Akaike information criterion as model selection criteria. The selected model was used to calculate odds ratios and 95% confidence intervals summarizing the association between prophylactic antibiotics and stent UTI while controlling for age, gender, and intra-operative urine cultures. RESULTS: 672 patients were included; 338 received antibiotic prophylaxis and 334 did not. These groups differed in mean age (3.91 vs. 6.91 years, P < .001), mean stent duration (38.5 vs. 35.32 days, P < .001), and surgical approach (53.25% vs. 32.04% open vs. laparoscopic, P < .001). The incidence of stent UTI was low overall (7.59%) and similar in both groups: 31/338 (9.17%) in the prophylaxis group and 20/334 (5.99%) in the non-prophylaxis group (P = .119). Although female gender, likely diaper use, and positive intra-operative urine culture were each associated with significantly higher odds of stent UTI, prophylactic antibiotic use was not associated with significant reduction in stent UTI in any of these groups. Surgical approach, stent duration, and Foley duration were not associated with stent UTI. CONCLUSION: Incidence of stent UTI is low overall following pyeloplasty. Prophylactic antibiotics are not associated with lower rates of stent UTI following pyeloplasty even after controlling for risk factors of female gender, likely diaper use, and positive intra-operative urine culture. Routine administration of prophylactic antibiotics after pyeloplasty does not appear to be beneficial, and may be best reserved for those with multiple risk factors for UTI.

An Akt- and Fra-1-dependent pathway mediates platelet-derived growth factor-induced expression of thrombomodulin, a novel regulator of smooth muscle cell migration.

Overdistension of hollow organs evokes pathological changes characterized by smooth muscle remodeling. Mechanical stimuli induce smooth muscle cell (SMC) growth through acute activation of signaling cascades and by increased expression of soluble mitogens. Physical forces have also been implicated in ligand-independent activation of receptor tyrosine kinases, including the platelet-derived growth factor (PDGF) receptor, although the extent to which this occurs in intact tissue is unknown. Previously, we implicated Akt and activator protein-1 (AP-1) as mediators of growth and gene expression in SMC exposed to cyclic stretch or PDGF. Here we show that bladder wall distension leads to PDGFR activation and identify thrombomodulin (TM) as an Akt and AP-1 target in SMC. We demonstrate that TM, also induced by bladder stretch injury, is regulated at the transcriptional level by the AP-1 components c-jun and Fra1. Mutation of an AP-1 motif at -2010/-2004 abolished both AP-1 binding and PDGF responsiveness of the TM promoter. Fra1 silencing diminished PDGF-induced TM expression and SMC cell cycle transit. In contrast, TM knockdown did not affect cell growth but attenuated PDGF-stimulated SMC migration. Taken together, these results reveal new facets of TM regulation in SMC and provide the first demonstration of a role for endogenous TM in PDGF-induced cell migration. Moreover, TM induction on bladder injury suggests that it may be a biomarker for pathological smooth muscle remodeling.

Prostatic cyst in a pediatric patient with autosomal dominant polycystic kidney disease.

Autosomal dominant polycystic kidney disease (ADPKD) is the most common inheritable form of renal cystic disease and is associated with cysts in other organs. Prostatic cysts are rare though and have not been reported in the paediatric population. Reported is the presence of a prostatic cyst that was incidentally noted on routine sonogram in a 15 year old with ADPKD.

Prospective evaluation of radiation dose with conventional fluoroscopic voiding cystourethrogram in pediatric patients.

INTRODUCTION: Skin entrance doses for voiding cystourethrogram (VCUG) have not been well characterized in the literature. Radiation exposure is measured as either dose area product (DAP) or air kerma, which estimates the effective dose, but does not accurately reflect absorbed dose at skin level. OBJECTIVE: The objective of this study was to measure the skin entrance dose during fluoroscopic VCUG study in pediatric patients using single point dosimeters. STUDY DESIGN: Pediatric patients undergoing fluoroscopic VCUG were prospectively enrolled in our study. Landauer NanoDot™OSLD dosimeters were affixed to the skin overlying the sacrum to measure skin entrance dose. The fluoroscopic unit was set to the following parameters: low dose setting, skin-to-source distance of 54 cm, pulsed fluoroscopy at 3 frames/sec. RESULTS: Forty-four patients with a median age of 13.6 months (IQR 3.7-42.3) were enrolled. Median fluoroscopic time was 54 s (IQR 36-72). The median values absorbed dose by dosimeter and air kerma were 0.32 mGy (IQR 0.13-0.56, range 0.01-2.9) and 0.24 mGy (IQR 0.14-0.37), respectively. There was a positive correlation between the air kerma and absorbed dose (r = 0.69, p < 0.001) and fluoroscopy time and absorbed dose mGy (r = 0.60, p < 0.001). Absorbed dose was independent of age, body mass index and body surface area (p = 0.19, p = 0.57 and p = 0.16, respectively). Median whole body effective dose was 0.04 mSv (IQR 0.02-0.7). DISCUSSION: Overall, the absorbed dose received by the dosimeter remained low at a median of 0.32 mGy (range 0.01-2.91). These values are remarkably low and well within the accepted radiation exposure norms. Our radiologists follow a strict protocol to reduce the overall radiation emitted during a VCUG. These measures include setting the x-ray source at a low dose mode, collimating to the smallest area possible, and using pulsed fluoroscopy at 3 frames/sec. Limitations to this study include a slight variability in technique of VCUG between different technicians and providers, for which we cannot control. CONCLUSION: The radiation dose absorbed at the skin entrance and uniform whole body effective dose is low for a single VCUG when utilizing strict parameters. While newer non-ionizing technologies continue to emerge, our data is encouraging and will serve as a valuable tool when educating parents regarding radiation doses associated with a VCUG.

Management strategies for Mayer-Rokitansky-Kuster-Hauser related vaginal agenesis: a cost-effectiveness analysis.

PURPOSE: The optimal method for neovagina creation in patients with vaginal agenesis is controversial. Progressive perineal dilation is a minimally invasive method with high success rates. However, the economic merits of progressive perineal dilation compared to surgical vaginoplasty are unknown. MATERIALS AND METHODS: We performed a Markov based cost-effectiveness analysis of 3 management strategies for vaginal agenesis-progressive perineal dilation with and without subsequent vaginoplasty, and up-front vaginoplasty. Cost data were drawn from the Pediatric Health Information System database (2004 to 2009) for inpatient procedures and from governmental cost data (2009) for outpatient procedures and clinical followup. Other model parameters were derived from a systematic literature review and comparison with other congenital and acquired pediatric and/or adolescent gynecologic conditions. Bounded and probabilistic sensitivity analyses were used to assess model stability. RESULTS: Including all procedures, equipment and physician visits, progressive perineal dilation had a mean cost of $796, while vaginoplasty cost $18,520. Up-front vaginoplasty was strongly dominated at any age, ie was more expensive but no more effective than other options. In cases of progressive perineal dilation failure the incremental cost-effectiveness ratio of progressive perineal dilation with subsequent vaginoplasty was $1,564 per quality adjusted life-year. Only the utility weights of life after treatment impacted model outcomes, while frequency of followup and probability of treatment success did not. CONCLUSIONS: Initial progressive perineal dilation followed by vaginoplasty in cases of dilation failure is the most cost-effective management strategy for vaginal agenesis. Initial vaginoplasty was less cost-effective than initial progressive perineal dilation in 99.99% of simulations.

Improvement in vesicoureteral reflux grade on serial imaging predicts resolution.

PURPOSE: When children are initially diagnosed with vesicoureteral reflux most undergo a period of antibiotic prophylaxis followed by serial imaging. Although improvement in reflux grade through time presumably predicts eventual resolution, the significance of changing grade through time is unknown. We examined whether improvement in reflux on serial imaging predicts resolution. MATERIALS AND METHODS: We retrospectively reviewed 1,761 children diagnosed with vesicoureteral reflux, of whom 965 had a minimum of 2 years of followup. We examined initial reflux grade and grade on serial imaging up to 5 years after the original diagnosis. For each child it was determined whether reflux was resolved, eventually resolved or never resolved. Groups were further stratified by clinical characteristics. RESULTS: Multivariate analysis revealed that male gender (HR 1.33, p = 0.05), age younger than 1 year at diagnosis (HR 1.35, p = 0.004), lower grade at presentation (grade I HR 2.2, grade II HR 1.96, grade III HR 1.33; p <0.001) and unilateral reflux (HR 1.39, p = 0.001) were all independent predictors of reflux resolution. Multivariate analysis also showed that reflux improvement on imaging 1 year after diagnosis (HR 3.14, p <0.0001) and improvement from the previous year at any point during followup (HR 1.8, p = 0.009) were independent predictors of reflux resolution. CONCLUSIONS: Consistent with previous findings, male gender, lower reflux grade at presentation, age less than 1 year at presentation and unilateral reflux were all predictive of reflux resolution. Our analysis also demonstrated that improvement in reflux grade on imaging study 1 year after diagnosis was predictive of resolution, and that reflux improvement from the previous year at any point during followup was an independent predictor of resolution. This information will prove valuable in clinical counseling and therapeutic decision making.

Variation among internet based calculators in predicting spontaneous resolution of vesicoureteral reflux.

PURPOSE: An increasing number of parents and practitioners use the Internet for health related purposes, and an increasing number of models are available on the Internet for predicting spontaneous resolution rates for children with vesicoureteral reflux. We sought to determine whether currently available Internet based calculators for vesicoureteral reflux resolution produce systematically different results. MATERIALS AND METHODS: Following a systematic Internet search we identified 3 Internet based calculators of spontaneous resolution rates for children with vesicoureteral reflux, of which 2 were academic affiliated and 1 was industry affiliated. We generated a random cohort of 100 hypothetical patients with a wide range of clinical characteristics and entered the data on each patient into each calculator. We then compared the results from the calculators in terms of mean predicted resolution probability and number of cases deemed likely to resolve at various cutoff probabilities. RESULTS: Mean predicted resolution probabilities were 41% and 36% (range 31% to 41%) for the 2 academic affiliated calculators and 33% for the industry affiliated calculator (p = 0.02). For some patients the calculators produced markedly different probabilities of spontaneous resolution, in some instances ranging from 24% to 89% for the same patient. At thresholds greater than 5%, 10% and 25% probability of spontaneous resolution the calculators differed significantly regarding whether cases would resolve (all p <0.0001). CONCLUSIONS: Predicted probabilities of spontaneous resolution of vesicoureteral reflux differ significantly among Internet based calculators. For certain patients, particularly those with a lower probability of spontaneous resolution, these differences can significantly influence clinical decision making.