Timing of follow-up voiding cystourethrogram in children with primary vesicoureteral reflux: development and application of a clinical algorithm

Endoscopic injection vs anti-reflux surgery for moderate- and high-grade vesicoureteral reflux in children: a cost-effectiveness international study

Even if vesicoureteral reflux is a common condition in children, there are no guidelines about the best therapeutic approach. This study aims to compare the results of endoscopic injection and ureteral reimplantation in children with grade III, IV and V VUR. A multicenter retrospective study included children with grade III, IV and V VUR treated from 2003 to 2018 at three Departments of Pediatric Surgery. Patients were divided into Group A (endoscopic injections) and Group B (anti-reflux surgery), B1 (open, OUR), B2 (laparoscopic, LUR) and B3 (robot-assisted laparoscopic RALUR). Follow-up was at least 5 years. 400 patients were included, 232 (58%) in group A and 168 (42%) in group B. Mean age at surgery was 38.6 months [3.1-218.7]. Mean follow-up was 177.8 months [60-240]. Group A had shorter operative time than group B (P < 0.01); lower analgesic requirement (p < 0.05), shorter hospital stay (P < 0.05) and lower overall costs (p < 0.05), but higher postoperative PNPs (p < 0.01), lower success rate (p < 0.01) and higher redo-surgery percentage (p < 0.01). No differences in terms of postoperative complications, success rate and mean radiation exposure between the two groups. Endoscopy is associated with shorter operative time, shorter hospitalization and lower cost, also in case of multiple injections. Recurrence rate after surgery is lower meaning lower rate of re-hospitalization and radiation exposure for children.

Evidence-based clinical practice guideline for management of urinary tract infection and primary vesicoureteric reflux

We present updated, evidence-based clinical practice guidelines from the Indian Society of Pediatric Nephrology (ISPN) for the management of urinary tract infection (UTI) and primary vesicoureteric reflux (VUR) in children. These guidelines conform to international standards; Institute of Medicine and AGREE checklists were used to ensure transparency, rigor, and thoroughness in the guideline development. In view of the robust methodology, these guidelines are applicable globally for the management of UTI and VUR. Seventeen recommendations and 18 clinical practice points have been formulated. Some of the key recommendations and practice points are as follows. Urine culture with > 104 colony forming units/mL is considered significant for the diagnosis of UTI in an infant if the clinical suspicion is strong. Urine leukocyte esterase and nitrite can be used as an alternative screening test to urine microscopy in a child with suspected UTI. Acute pyelonephritis can be treated with oral antibiotics in a non-toxic infant for 7-10 days. An acute-phase DMSA scan is not recommended in the evaluation of UTI. Micturating cystourethrography (MCU) is indicated in children with recurrent UTI, abnormal kidney ultrasound, and in patients below 2 years of age with non-E. coli UTI. Dimercaptosuccinic acid scan (DMSA scan) is indicated only in children with recurrent UTI and high-grade (3-5) VUR. Antibiotic prophylaxis is not indicated in children with a normal urinary tract after UTI. Prophylaxis is recommended to prevent UTI in children with bladder bowel dysfunction (BBD) and those with high-grade VUR. In children with VUR, prophylaxis should be stopped if the child is toilet trained, free of BBD, and has not had a UTI in the last 1 year. Surgical intervention in high-grade VUR can be considered for parental preference over antibiotic prophylaxis or in children developing recurrent breakthrough febrile UTIs on antibiotic prophylaxis.

Cost-Effectiveness of Screening Ultrasound after a First, Febrile Urinary Tract Infection in Children Age 2-24 Months

OBJECTIVE

To estimate the cost-effectiveness of routine, screening renal bladder ultrasound (RBUS) for children age 2-24 months after a first febrile urinary tract infection (UTI), as recommended by the American Academy of Pediatrics.

STUDY DESIGN

We developed a decision analytic model that simulates a population of children after a first febrile UTI. The model incorporates the diagnostic utility of RBUS to detect vesicoureteral reflux and genitourinary anomalies. We adopted a health-system perspective, 5-year horizon, and included 1-way and 2-way sensitivity analyses. Costs were inflated to 2018 US dollars, and our model incorporated a 3% discounting rate. We compared routine RBUS after first, febrile UTI compared with routine RBUS after second UTI (ie, control arm). Our main outcomes were recurrent UTI rate and incremental cost per quality-adjusted life-year (QALY).

RESULTS

Among children 2-24 months after a first febrile UTI, RBUS had an overall accuracy (true positives + true negatives) of 64.4%. The recurrent UTI rate in the intervention arm was 19.9% compared with 21.0% in the control arm. Thus, 91 patients would need to be screened with RBUS to prevent 1 recurrent UTI. RBUS increases QALYs by +0.0002 per patient screened, corresponding to an incremental cost-effectiveness ratio of $803 000/QALY gained. In the RBUS arm, 20.6% of children would receive unnecessary voiding cystourethrograms compared with 12.2% of children in the control group.

CONCLUSIONS

Screening RBUS after a first, febrile UTI in children age 2-24 months does not meet cost-effectiveness guidelines. Our findings support deferred screening until a second UTI.

Pediatric voiding cystourethrography: An essential examination for urologists but a terrible experience for children

Voiding cystourethrography is the most important fluoroscopic examination in pediatric urology for the investigation of lower urogenital tract diseases, such as vesicoureteral reflux or urethral stricture. However, this invasive procedure imposes a significant burden on children and their parents, and recently there has been a paradigm shift in the diagnosis and treatment of vesicoureteral reflux. In the 2011 revision, the American Academy of Pediatrics guidelines on urinary tract infection recommended abandoning routine voiding cystourethrography after the first febrile urinary tract infection. In 2014, the randomized intervention for children with vesicoureteral reflux study recommended discontinuation of routine continuous antibiotic prophylaxis for vesicoureteral reflux. The time is now ripe to radically reconsider indications for voiding cystourethrography and the procedure itself.

Comparing between results and complications of doing voiding cystourethrogram in the first week following urinary tract infection and in 2-6 weeks after urinary tract infection in children referring to a teaching hospital

Introduction: Urinary tract infection is the most common genitourinary disease in children so about 40% of the children with urinary tract infection suffering from reflux that caused some consequences such as pyelonephritis and kidney parenchymal injury.

Objectives: This research was conducted to compare the timing of voiding cystourethrogram (VCUG) in children with urinary tract infection in first week and after the first week of urinary tract infection.

Patients and Methods: This research is a case-control study that both case and control groups include 208 children from 1 month to 12 years old with the complain of urinary tract infection. In case group, the VCUG was performed at the first week of infection and in control group, the VCUG was performed after the first week of infection.

Results: complication such as dysuria was observed in two-thirds of children who VCUG was performed during first week after urinary tract infection. Parents stress in case group was more than the other (P=0.015). For overall, the incidence of reflux in case and control groups was 49.5% and 50%, respectively. The mean of reflux grading in right kidney in case group was lower than control group resulting in significant differences between two groups.

Conclusion: According to higher grade of stress in parents and complications due to VCUG at the first week of urinary tract infection, it is suggested that VCUG be conducted on selective patients in the hospital at the first week of urinary tract infection and during hospitalization.

Reliability of voiding cystourethrogram for the grading of vesicoureteral reflux

OBJECTIVE

The voiding cystourethrogram (VCUG) is a commonly employed radiographic test used in the management of vesicoureteral reflux (VUR). Recently, the reliability of VCUG to accurately grade VUR has been questioned. The purpose of this study is to examine reliability of the VCUG for the grading of VUR in a setting mimicking daily practice in a busy pediatric hospital.

MATERIALS AND METHODS

Two-hundred consecutive VCUGs were independently graded by two pediatric urologists and two pediatric radiologists according to the International Classification of Vesicoureteral Reflux. A weighted kappa coefficient was calculated to determine inter-rater agreement and a modified McNemar test was performed to assess rater bias. Further assessment for impact on clinical and research decision-making was made for disagreement between grades II and III.

RESULTS

Weighted kappa values reflect strong reliability of VCUG for grading VUR between and among urologists and radiologists ranging from 0.95 to 0.97. There was statistically significant bias with radiologists reporting higher grades. Despite high kappa values, disagreement between raters was not infrequent and most common for grades II-IV.

CONCLUSIONS

VCUG is reliable for grading VUR, but small differences in grading between raters were detected and may play an important role in clinical decision-making and research outcomes.

Does routine ultrasound change management in the follow-up of patients with vesicoureteral reflux?

INTRODUCTION

Children with vesicoureteral reflux (VUR) usually need a renal ultrasound (RUS). There is little data on the role of follow-up RUS in VUR. We evaluated the impact of follow-up RUS on the change in clinical management in patients with VUR.

METHODS

We prospectively analyzed children with a previous diagnosis of VUR seen in the outpatient clinic with a routine follow-up RUS within 4 months. Variables collected included: demographic data, VUR history, dysfunctional voiding symptoms and concurrent ultrasound findings. Change in management was defined as addition of new medication, nurse counselling, surgery or further investigations.

RESULTS

The study included 114 consecutive patients. The mean patient age was 4.5 years old, mean age of VUR diagnosis was 1.7 years, with average follow-up of 2.8 years. A change in management with stable RUS occurred in 14 patients, in which the change included ordering a DMSA in 9, nurse counselling for dysfunctional voiding in 3, and booking surgery in 2 patients. Change on RUS was seen in 4 patients. Multivariable analysis showed that history of urinary tract infection (UTI) since the last follow-up visit was more significant than RUS findings.

CONCLUSIONS

The RUS findings in most patients followed for VUR remain stable or with minimal changes. The variable showing a significant effect on change in management in our study was history of UTI since the last follow-up visit rather than RUS findings. The value of follow-up RUS for children with VUR may need to be revisited.

Genetic algorithm pruning of probabilistic neural networks in medical disease estimation

A hybrid model consisting of an Artificial Neural Network (ANN) and a Genetic Algorithm procedure for diagnostic risk factors selection in Medicine is proposed in this paper. A medical disease prediction may be viewed as a pattern classification problem based on a set of clinical and laboratory parameters. Probabilistic Neural Network models were assessed in terms of their classification accuracy concerning medical disease prediction. A Genetic Algorithm search was performed to examine potential redundancy in the diagnostic factors. This search led to a pruned ANN architecture, minimizing the number of diagnostic factors used during the training phase and therefore minimizing the number of nodes in the ANN input and hidden layer as well as the Mean Square Error of the trained ANN at the testing phase. As a conclusion, a number of diagnostic factors in a patient's data record can be omitted without loss of fidelity in the diagnosis procedure.

Diagnostic approach to reflux in 2007

There is ongoing controversy regarding the association between vesicoureteric reflux (VUR), recurrent urinary tract infections (UTI), and renal damage. Despite this, routine work up for VUR is still recommended after febrile UTI in most children. The present article reviews the indications and imaging modalities available for VUR diagnosis. Alternative newer techniques like MR cystography and voiding urosonography are discussed. The increasing evidence of the role of DMSA scans in managing children with VUR is highlighted.

Anxiety in children undergoing VCUG: sedation or no sedation?

BACKGROUND

Voiding cystourethrograms are distressing for children and parents. Nonpharmacological methods reduce distress. Pharmacological interventions for VCUG focus on sedation as well as analgesia, anxiolysis, and amnesia. Sedation has cost, time, and safety issues. Which agents and route should we use? Are we sure that sedation does not influence the ability to diagnose vesicoureteric reflux?

METHODS

Literature search of Medline, EMBASE, and the Cochrane Database. Review of comparative studies found.

RESULTS

Seven comparative studies including two randomised controlled trials were reviewed. Midazolam given orally (0.5-0.6 mg/kg) or intranasally (0.2 mg/kg) is effective with no apparent effect on voiding dynamics. Insufficient evidence to recommend other sedating agents was found. Deeper sedating agents may interfere with voiding dynamics.

CONCLUSION

Midazolam reduces the VCUG distress, causes amnesia, and does not appear to interfere with voiding dynamics. Midazolam combined with simple analgesia is an effective method to reduce distress to children undergoing VCUG.

The current evidence based medical management of vesicoureteral reflux: The Sickkids protocol

Vesicoureteral reflux is a common clinical entity and is one of the keystones of the establishment of pediatric urology as a urological subspeciality. There has been continued evolution in the management of vesicoureteral reflux as new insights are gained on its role in renal damage. The optimal treatment algorithm remains controversial. This review aims to highlight the current literature on VUR and its association with urinary tract infections and renal damage. The protocol of management of a child with VUR followed at The Hospital for Sick Children, Toronto is described.

Voiding urosonography as first step in the diagnosis of vesicoureteral reflux in children: a clinical experience

BACKGROUND

Contrast-enhanced voiding urosonography (VUS) is becoming more widely used for the diagnosis of vesicoureteric reflux (VUR), but until now its use has only been accepted for first diagnosis in females and in the follow-up of children, including boys, who have already undergone voiding cystourethrography (VCUG).

OBJECTIVE

To describe our 6-year experience with VUS used as a first step in the diagnosis of VUR.

MATERIALS AND METHODS

A total of 610 children (334 boys, 276 girls; mean age 22 months), underwent VUS as the first step in the diagnosis of VUR. In selected children, VCUG was also performed.

RESULTS

VUR was detected in 199 of 610 VUS examinations, and 265 refluxing kidney-ureter units were found. Children with VUR underwent antibiotic prophylaxis or surgery. Children without VUR underwent clinical follow-up. Just 60 children underwent VCUG. The criteria for VCUG were: high-grade VUR after consultation with a urologist, onset of urinary tract infection while receiving prophylaxis, nondiagnostic VUS, and other malformations with or without clinical signs.

CONCLUSION

Our experience suggests that we can use VUS as the first step in the diagnosis of VUR in children, boys and girls, with a significant reduction in radiation exposure.

Imaging strategies for vesicoureteral reflux diagnosis

The prevalence of vesicoureteral reflux (VUR), although reported to be low in the general population, is high in children with urinary tract infection (UTI), first degree relatives of patients with known VUR and children with antenatal hydronephrosis. In addition, it has been shown that VUR and UTIs are associated with renal scarring, predisposing to serious long-term complications, i.e., hypertension, chronic renal insufficiency and complications of pregnancy. Therefore, diagnostic imaging for the detection of VUR in the high-risk groups of children has been a standard practice. However, none of these associations has been validated with controlled studies, and recently the value of identifying VUR after a symptomatic UTI has been questioned. In addition, several studies have shown that renal damage may occur in the absence of VUR. On the other hand, some patients, mainly males, may have primary renal damage, associated with high-grade VUR, without UTI. Recently, increasing skepticism has been noted concerning how and for whom it is important to investigate for VUR. It has been suggested that the absence of renal lesions after the first UTI in children may rule out VUR of clinical significance and reinforces the redundancy of invasive diagnostic techniques. Therefore, the priority of imaging strategies should focus on early identification of renal lesions to prevent further deterioration.

Ordering of renal tract imaging by paediatricians after urinary tract infection

AIM

To describe paediatricians' reported ordering of renal tract imaging of children following urinary tract infection.

METHODS

This is a piloted self-administered survey. A total of 354 randomly sampled practising paediatricians in Australia participated in the survey. The survey included 12 clinical scenarios that varied with age, gender and fever. Respondents indicated their likelihood of ordering renal ultrasound, micturating cystourethrogram (MCU) and dimercaptosuccinic acid scan (DMSA) from 0 to 100%.

RESULTS

Response rate was 74.6% (264/354). For all clinical scenarios the median probability of ordering an ultrasound was 100% with little variability. For children aged 2 months, likelihood of ordering an MCU was 100%, with little variability, but was 70% for 3-year-olds with fever (45% without fever), and 5% for 6-year-olds with very large variability. Median likelihood of ordering a DMSA was 80% at 2 months, 60% at 3 years and 20% at 6 years (40%, 15%, 5% without fever, respectively). Variability was large for all scenarios and DMSA ordering. Child gender did not influence ordering practices.

CONCLUSIONS

Renal tract imaging practice across paediatricians shows consistent, approximately 100% use of the least invasive modality, ultrasound. In contrast, there is considerable variation in the reported ordering of the more invasive tests MCU and DMSA. Doctors order these tests more in younger children and when fever is present.

Cost-Utility Analysis of Treatment Algorithms for Moderate Grade Vesicoureteral Reflux Using Markov Models

PURPOSE

The optimal treatment algorithm for vesicoureteral reflux remains controversial. Previous decision analyses have attempted to determine the best approach solely from the cost or cure perspective but have not combined the goals of minimizing treatment and disease burden. We incorporated these considerations into a contemporary, comprehensive analysis of treatment for vesicoureteral reflux.

MATERIALS AND METHODS

We examined costs from the perspective of the medical institution, and utility from the perspective of parents of children with grades II and III vesicoureteral reflux. Cost-utility analysis using Markov modeling was performed to ascertain which of 5 treatment algorithms best minimized morbidity and cost. A higher utility value was based on minimizing treatment and disease burden. Measures of treatment and disease burden included duration of suppressive antibiotics, number of invasive studies, pyelonephritis episodes, endoscopic treatments and open operations. All variables were varied spanning realistic ranges during sensitivity analyses to determine threshold values.

RESULTS

The protocol of no antibiotics or followup imaging yielded the best cost-utility for vesicoureteral reflux grades II and III. Sensitivity analysis of variables spanning realistic ranges demonstrated that utility penalties for invasive imaging and outpatient pyelonephritis were particularly important in determining the highest utility protocols, with threshold values ranging from -0.5 to -0.8.

CONCLUSIONS

In our models of treatment for vesicoureteral reflux a noninterventional approach constitutes the highest utility and least costly treatment for moderate grade reflux. Given the relative dearth of randomized trials, these analyses provide guidelines for current management of vesicoureteral reflux.

Medical management of vesicoureteral reflux--quiz within the article. Don't overlook placebos

Vesicoureteral reflux (VUR) in children is associated with increased risk of urinary tract infection (UTI). Recurrent UTI in the presence of the VUR is believed to cause renal scarring, which carries a risk of subsequent hypertension, toxemia of pregnancy, and significant renal damage, including end-stage renal disease. The natural history of VUR is to improve or resolve completely with time in most of the patients. The traditional management consists of prompt treatment of UTI, long-term anti-microbial prophylaxis until the VUR resolves, or surgical intervention in those with persistent high grade VUR, recurrent UTI in spite of prophylaxis with anti-microbial agent, allergy to anti-microbial agents, and patient/parent non-compliance with the medical management. Voiding dysfunction and constipation play an important role, and their diagnosis and appropriate management helps reduce the frequency of UTI and promote the resolution of the VUR. Patients with renal scarring need to be monitored for potential complications such as hypertension, proteinuria, and progression of the renal damage. In patients with hypertension and/or proteinuria, angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin II receptor blockers (ARBs) are the drugs of choice, because of their reno-protective properties. Recent studies have revealed that there is no convincing evidence that UTI in the presence of VUR predicts renal injury or that the use of long-term anti-microbial prophylaxis or surgical intervention prevents renal scarring or its progression. However, until proven otherwise by a prospective, placebo-controlled, randomized study, it is advisable to err on the side of caution and consider VUR and UTI risk factors for renal scarring and treat each patient on individual basis.

A locus for renal malformations including vesico-ureteric reflux on chromosome 13q33-34

Congenital anomalies of kidney and urinary tract (CAKUT), including vesico-ureteric reflux (VUR), are major causes of ESRD in childhood. Herein is reported evidence for a locus on 13q33q34 associated with CAKUT. Deletion mapping of chromosome 13q was performed in four children with CAKUT using 31 microsatellite markers on peripheral blood genomic DNA that was obtained from the patients and their parents. mRNA expression of the positional candidate genes was compared with sequences in electronic databases in silico and also studied in adult and fetal mouse kidneys using reverse transcription-PCR. The children (three girls; age range 5 to 17 yr) had varying severity of developmental delay and other organ system involvement. The spectrum of CAKUT included high-grade VUR (n = 2), renal dysplasia (n = 2), and hydronephrosis (n = 1). Both the children with VUR had evidence of renal failure with one of them developing ESRD. Deletion mapping identified a 7-Mb critical region flanked by markers D13S1311 and D13S285. There are 33 genes (12 known; 21 computer predicted) in this region. In silico expression studies showed matches for 14 of these genes in the kidneys and 10 in the bladder expressed sequenced tags databases. Mouse kidney studies showed that of the 24 genes examined, several had variable expression through the different stages of renal development, whereas five of the genes were not expressed at all. Herein is reported a new locus on chromosome 13q33q34 that can be associated with VUR with several genes showing mRNA expression patterns that suggest their potential for involvement in renal/urinary tract developmental anomalies.

Applying the ALARA concept to the evaluation of vesicoureteric reflux

The voiding cystourethrogram (VCUG) is a widely used study to define lower urinary tract anatomy and to diagnose vesicoureteric reflux (VUR) in children. We examine the technical advances in the VCUG and other examinations for reflux that have reduced radiation exposure of children, and we give recommendations for the use of imaging studies in four groups of children: (1) children with urinary tract infection, (2) siblings of patients with VUR, (3) infants with antenatal hydronephrosis (ANH), and (4) children with a solitary functioning kidney. By performing examinations with little to no radiation, carefully selecting only the children who need imaging studies and judiciously timing follow-up examinations, we can reduce the radiation exposure of children being studied for reflux.

Vesicoureteric reflux and urinary tract infection in children

An association between vesicoureteric reflux (VUR) and renal damage was found in 1960. In 1973, the term reflux nephropathy (RN) was first used to describe the renal damage caused by VUR. Follow up studies show that about 10%-20% of children with RN develop hypertension or end stage renal disease. It is now evident that there is a sex difference in the development of RN. In most males with RN, the kidneys are congenitally abnormal. In females it is an acquired condition, the most severe damage being sustained by recurrent urinary tract infections (UTIs). The purpose of current UTI guidelines is to identify VUR or any other abnormality of the urinary tract. Since the advent of routine antenatal ultrasonography, there is no longer a need to identify an abnormality of the urinary tract after the first reported UTI. Routine investigations are not required. Recurrent UTIs and a family history of VUR need further evaluation. There is also an urgent need to establish the long term value of prophylactic antibiotics in children with VUR.

Predictive factors of resolution of primary vesico-ureteric reflux: a multivariate analysis

OBJECTIVE

To identify independent factors predicting the resolution of primary vesico-ureteric reflux (VUR) in a cohort of medically managed children.

PATIENTS AND METHODS

Between 1977 and 2003, 506 children were diagnosed with VUR and were conservatively managed and prospectively followed. All of the children were maintained on antibiotic prophylaxis. Follow-up imaging consisted of voiding cysto-urethrography (VCUG) or a direct isotope cystogram at intervals of 2-3 years. The predictive factors used are based on the patient data at the time of entry in the protocol. The dependent variable was VUR resolution. The criterion for resolution was based on a single negative VCUG or direct isotope cystogram. A survival analysis identified variables significantly associated with VUR resolution. Cox's regression model was applied to identify variables independently associated with the dependent variable.

RESULTS

After adjustment, four variables remained as independent predictors of VUR resolution: nonwhite race, relative risk (95% confidence interval) of 1.5 (1.1-1.9; P = 0.009); mild grade of VUR, 3.3 (2.1-5.3; P < 0.001); absence of renal damage, 3.3 (2.4-4.5; P < 0.001); and absence of dysfunctional voiding, 2.0 (1.4-3.1; P < 0.001). For mild VUR, three variables were significantly associated: male gender, 1.7 (1.1-2.6; P = 0.012); absence of renal damage, 3.4 (1.8-6.4; P < 0.001); and unilateral VUR, 1.6 (1.1-2.3; P = 0.004). For moderate/severe VUR, three variables were significantly associated: nonwhite race, 1.7 (1.1-2.6; P = 0.01); absence of renal damage, 3.0 (2.0-4.4; P < 0.001); and absence of dysfunctional voiding, 2.8 (1.4-5.5; P = 0.004).

CONCLUSION

Few factors are amenable to intervention to modify the natural history of VUR. According to our findings, there are only two possible interventions: avoiding renal scars and managing voiding dysfunction.

Vesicoureteral reflux

Vesicoureteral reflux, the abnormal flow of urine from the bladder into the ureter, is one of the most common congenital anomalies found in children. The association of vesicoureteral reflux with urinary tract infections and renal scarring has important clinical implications. New insights into pathogenesis and new surgical techniques are changing the approach to the management of this disorder.

Clinical decision rules in radiology

Clinical decision rules to guide physicians in the appropriate use of diagnostic imaging studies need to be developed, in part, to control the overutilization of imaging studies. These rules need to be evidence based. Randomized control trials can be designed to assess the value of imaging studies and interventional procedures at levels five and six, patient outcome and societal efficacies, in Fryback and Thornbury's hierarchical model of efficacy. Results of these trials can be used to develop clinical decision rules. However, the efficacy of most diagnostic imaging studies can be assessed better at levels three and four, diagnostic thinking and therapeutic efficacies. Studies can be designed to determine clinical situations in which imaging studies will be of no value or to determine clinical criteria for the use of imaging studies. Systematic reviews of the literature and other techniques of analysis of evidence, such as decision trees, also can be used to develop evidence-based clinical decision rules for the use of diagnostic imaging procedures.

Clinical course of prenatally detected primary vesicoureteral reflux

The purpose of this study was to report the clinical course of medium-long-term follow-up of children with prenatally detected vesicoureteral reflux (VUR). Between 1986 and 2004, 53 (41 males) children with VUR detected by investigation of prenatal hydronephrosis were followed up for a mean time of 66 months (range: 6-200 months). Newborns were investigated by ultrasound, voiding cystourethrogram (VCUG) and DMSA scan. Follow-up clinical visits were performed at 6-month intervals. After 24 months patients were investigated by conventional VCUG or direct isotope cystogram. Survival analysis was performed in order to evaluate the resolution of the reflux. Differences between subgroups (mild vs moderate/severe reflux) were assessed by the two-sided log rank test. Thirty (58%) infants presented bilateral VUR, for a total of 83 renal units. There was a predominance of severe reflux (54%). Renal damage was detected in 33.7% of the units on first renal scan. There was a significant correlation between severe reflux and renal damage scars (RR=3.4, 95% confidence interval [CI], 1.4-8, p=0.002). Forty-seven patients were treated with continuous prophylaxis. One patient developed systolic hypertension. Urinary tract infection occurred in 12 (25%) children conservatively managed. VUR resolution was evaluated in 56 renal units. Spontaneous resolution was observed in 25 units (45%). At 48 months after diagnosis, 75% of the cases of mild reflux (I-III) and 37% of severe reflux (IV-V) had resolved (log-rank, 5.6, p=0.017). There was an improvement of nutritional parameters between admission and the end of follow-up. In conclusion, the clinical course of prenatally detected VUR followed up on a medium-long-term basis is relatively benign. Our study corroborates the results obtained in other series of infants with reflux that emphasized the heterogeneity of this disorder.