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

New trends in voiding cystourethrography and vesicoureteral reflux: Who, when and how?

Vesicoureteral reflux, retrograde flow of urine from the bladder into the upper urinary tract, is one of the most common urological diagnoses in the pediatric population. Diagnosis and subsequent management of urinary reflux have become increasingly debated in the past decade, with divergent opinions over which patients should be evaluated for reflux, and when detected, which children should receive intervention. Although some argue that vesicoureteral reflux is a "phenotype" that often resolves without intervention, others contest that untreated reflux has the potential to cause irreversible renal damage over time. Voiding cystourethrogram images the urethra and bladder during both bladder filling and emptying, as well as the ureters and kidneys when reflux is present, and is considered the gold standard for diagnosing vesicoureteral reflux. Once detected, therapeutic options for urinary reflux are diverse, ranging from observation with or without low-dose antibiotic prophylaxis to a variety of operative interventions. Management should be based on a multitude of factors including patient age, risk of subsequent urinary tract infections, risk of renal parenchymal injury, a given child's projected clinical course and parental preference. Over the past two decades, investigators have elucidated many crucial voiding cystourethrogram findings in addition to grade that provide significant prognostic information and are useful in determining the best course of action for a child on a more individualized basis.

Computer model predicting breakthrough febrile urinary tract infection in children with primary vesicoureteral reflux

INTRODUCTION AND OBJECTIVE

Factors influencing the decision to surgically correct vesicoureteral reflux (VUR) include risk of breakthrough febrile urinary tract infection (fUTI) or renal scarring, and decreased likelihood of spontaneous resolution. Improved identification of children at risk for recurrent fUTI may impact management decisions, and allow for more individualized VUR management. We have developed and investigated the accuracy of a multivariable computational model to predict probability of breakthrough fUTI in children with primary VUR.

STUDY DESIGN

Children with primary VUR and detailed clinical and voiding cystourethrogram (VCUG) data were identified. Patient demographics, VCUG findings including grade, laterality, and bladder volume at onset of VUR, UTI history, presence of bladder-bowel dysfunction (BBD), and breakthrough fUTI were assessed. The VCUG dataset was randomized into a training set of 288 with a separate representational cross-validation set of 96. Various model types and architectures were investigated using neUROn++, a set of C++ programs.

RESULTS

Two hundred fifty-five children (208 girls, 47 boys) diagnosed with primary VUR at a mean age of 3.1 years (±2.6) met all inclusion criteria. A total 384 VCUGs were analyzed. Median follow-up was 24 months (interquartile range 12-52 months). Sixty-eight children (26.7%) experienced 90 breakthrough fUTI events. Dilating VUR, reflux occurring at low bladder volumes, BBD, and history of multiple infections/fUTI were associated with breakthrough fUTI (Table). A 2-hidden node neural network model had the best fit with a receiver operating characteristic curve area of 0.755 for predicting breakthrough fUTI.

DISCUSSION

The risk of recurrent febrile infections, renal parenchymal scarring, and likelihood of spontaneous resolution, as well as parental preference all influence management of primary VUR. The genesis of UTI is multifactorial, making precise prediction of an individual child's risk of breakthrough fUTI challenging. Demonstrated risk factors for UTI include age, gender, VUR grade, reflux at low bladder volume, BBD, and UTI history. We developed a prognostic calculator using a multivariable model with 76% accuracy that can be deployed for availability on the Internet, allowing input variables to be entered to calculate the odds of an individual child developing a breakthrough fUTI.

CONCLUSIONS

A computational model using multiple variables including bladder volume at onset of VUR provides individualized prediction of children at risk for breakthrough fUTI. A web-based prognostic calculator based on this model will provide a useful tool for assessing personalized risk of breakthrough fUTI in children with primary VUR.

Vesicoureteral reflux index (VURx): a novel tool to predict primary reflux improvement and resolution in children less than 2 years of age

PURPOSE

Surgical correction of vesicoureteral reflux (VUR) is influenced by recurrent urinary tract infection (UTI) risk and the likelihood of spontaneous resolution. We aimed to identify factors associated with VUR resolution in children less than 2 years of age and to design a simple scoring tool to predict improvement and resolution.

MATERIALS AND METHODS

Children less than 2 years old with primary VUR were identified. Patient demographics, voiding cystourethrogram (VCUG) findings and clinical outcomes over time were assessed. Multivariate analysis with time to resolution was performed to identify factors predictive of VUR improvement and resolution. A random forest model was used to confirm the VUR index (VURx) with normalized importance.

RESULTS

Two-hundred and twenty-nine children met all inclusion criteria. Mean age at initial VCUG was 0.46±0.43 years. Median clinical follow-up was 1.6 years (range 0.5-4.4 years). Children with grade 4-5 reflux, complete ureteral duplication or periureteral diverticula, and filling phase VUR, as well as female gender, had significantly (p<0.01) longer time to improvement or resolution on multivariate survival analysis. VURx 1 to 5-6 had improvement/resolution rates of 89%, 69%, 53%, 16% and 11%, respectively.

CONCLUSIONS

Female gender, high-grade VUR, ureteral anomalies, and filling reflux are associated with longer time to improvement and non-resolution. VURx reliably predicts resolution of primary reflux in children less than 2 years of age.

Relevance of current guidelines in the management of VUR

In recent years, there have been fundamental changes in the understanding of vesicoureteral reflux (VUR). This is reflected by current international guidelines that cover diagnosis, screening, and treatment of VUR. However, literature is still lacking and many questions are unsolved. In this article, we shortly review the important aspects of the current guidelines. Due to the lack of high-powered randomized controlled trials, guidelines often are based on an expert's opinion rather than evidence. In this review article, we address the controversies in the management of VUR; siblings and children with antenatally diagnosed hydronephrosis and the management of a patient with VUR.

CONCLUSION

With an individualized approach and patient risk stratification, the goal today must be to address the clinical problem, avoid unnecessary tests, and provide good quality of life for the patient and parents.