The relationship between early renal status, and the resolution of vesico-ureteric reflux and bladder function at 16 months

A scoring system for predicting downgrading and resolution of high-grade infant vesicoureteral reflux

AIM

Aim of the study was to provide a scoring system for predicting downgrading and resolution of infantile high-grade vesicoureteral reflux (VUR).

METHODS

Eighty-nine infants (65 boys) with high-grade VUR (grade 4-5) diagnosed at median age 2.5 months and followed to 39 months had repeated investigations of VUR grade, renal damage/function and bladder function. Recurrent urinary tract infections (UTIs) were registered. Risk variables collected at 1 year were analysed as independent factors for spontaneous resolution to grades ≤2 and 0, using univariable/multivariable logistic regression.

RESULTS

A scoring system was built with a total of 14 points from four independent risk factors (sex, breakthrough UTI, type of renal damage and subnormal glomerular filtration rate). Children with persistent VUR (grade 3-5) had higher scores compared with the group with spontaneous resolution (grade 0-2) (mean 7.9 vs. 4.5, P < .0001). A score of ≥8 points indicated a low probability of VUR resolution (≤14%). The model was considered excellent based on area under the ROC curve (0.82) and showed satisfactory internal validity.

CONCLUSION

This model provides a practical tool in the management of infants born with high-grade reflux. High scores at one year of age indicate a high risk of persistent dilated reflux.

Renal scarring is the most significant predictor of breakthrough febrile urinary tract infection in patients with simplex and duplex primary vesico-ureteral reflux

INTRODUCTION

The association of high-grade vesico-ureteral reflux (VUR) with renal dysplasia and/or scarring is well-established, and the combination of these factors has been shown to decrease the likelihood of VUR resolution. Other VUR parameters have similarly been shown to be associated with VUR non-resolution, including VUR grade and timing at cystography, associated urinary tract anatomical abnormalities, and bladder dysfunction.

OBJECTIVE

To establish independent risk factors that can predict symptomatic persistence of VUR.

DESIGN

This was a single-centre study (2011-2017) including consecutive prospectively collected patients with primary VUR on voiding cystourethrogram (VCUG). Patients with dilating VUR also underwent renography (dimercaptosuccinic acid [DMSA] or 99m-technetium mercaptoacetyltriglycine [^99mTc-MAG3]). All patients were initially managed medically with antibiotic prophylaxis. Primary outcome was febrile culture-positive breakthrough urinary tract infection (BT-UTI). Demographic parameters, as well as VUR grade, VUR timing at cystography, presence of ureteral anomaly, VUR index (VURx), and differential renal function (DRF) or scarring were analysed to determine independent predictors.

RESULTS

A total of 61 patients (41 male, of whom 7 circumcised at presentation) were studied. VUR was diagnosed following investigation of prenatal hydronephrosis in 37 patients (62%) and following a febrile UTI in 22 (37%). Median [range] follow-up period was 38 [12-84] months. Data from a total of 77 refluxing renal units (RUs) were used for analysis. Analysis of VCUG data demonstrated that high VURx might be a potential significant predictor of breakthrough UTI (RR: 1.7, 95% CI: 1.1-2.7, p < 0.05 vs low VURx) but this was not the case for individual VURx components. Renography data showed increased risk of breakthrough UTI in patients with renal scarring (relative risk (RR): 5.1, 95% confidence interval (CI: 2.0-10.7, p < 0.0001 vs no renal scarring), but not in patients with reduced DRF. Multivariate regression analysis revealed that renal scarring was the only significant risk factor for breakthrough UTI. VUR patients with renal scarring were three times more likely to develop breakthrough UTI (odds ratio (OR): 3.3, 95% CI: 1.4-7.4, p < 0.01).

DISCUSSION

Multiple factors have been shown to be significant predictors of radiological VUR resolution. Univariate analysis of these factors suggests that only scarring on DMSA and VURx are significant predictors of symptomatic non-resolution. On multivariate analysis, scarring on DMSA was the only significant predictive variable. This information will be useful in targeting investigation and treatment in susceptible patients and when counselling families.

CONCLUSION

Renal scarring is the most significant risk factor for breakthrough UTI in primary VUR patients and could be used to determine those at risk of symptomatic VUR persistence.

Surgical outcome of patients with vesicoureteral reflux from a single institution in reference to the ESPU guidelines: a retrospective analysis

INTRODUCTION

Vesicoureteral reflux (VUR) is an anatomic or functional disorder, and it is a condition associated with renal scarring, hypertension, and end-stage renal disease. Renal damage can be prevented by appropriate medical and surgical intervention for selected patients.

OBJECTIVES

The objective of this study was to retrospectively analyze the surgically treated patient group of this study in reference to the risk analysis criteria used in European Association of Urology (EAU), European Society for Paediatric Urology (ESPU) guidelines to see the outcome of the study management protocol within the last 15 years in respect to this risk analysis.

STUDY DESIGN

A total of 686 patients who were operated upon in a single institution for VUR between 1997 and 2016 were retrospectively analyzed. According to the criteria in EAU/ESPU guidelines, the patients were classified into three groups: low, medium, and high risk. Risk factors were compared between the groups.

RESULTS

The patient numbers for low, medium, and high risk were 92 (13.4%), 485 (70.7%), and 109 (15.9%), respectively. In the high-risk group, surgeons tended to do more ureteroneocystostomy (UNC) (82.6%), whereas in the low-risk group, surgeons tended to do more subureteric injection (STING) (76.1%). The success rates for STING and UNC were found to be 75% and 93%, respectively. Although there was a difference in success rates among patients treated with STING or UNC, this difference was not statistically significant in success rates regarding risk groups for patients treated with STING or UNC.

DISCUSSION

The most recent guideline was that which was published by the EAU/ESPU organization in 2012. This guideline is established based on the risk analysis. The analysis revealed that patients in the low-risk group tended to undergo endoscopic surgery treatment method, whereas patients in the high-risk group tended to undergo open surgery. Therefore, the study management over the last 10 years has been mainly in line with the current recommendations.

CONCLUSION

The analysis shows that when the patients are classified according to the EAU/ESPU risk classification, surgeons tended to perform more endoscopic and more open surgery for the low- and high-risk groups, respectively. Although each surgical modality had similar success rates in each group, open surgical results were overall much higher than those of endoscopic surgery in each group. This was a specifically important finding in high-risk group where the endoscopically treated group of patients was small in number, and the need for a definitive correction is essential in this group because of increased risk of renal injury.

The Swedish infant high-grade reflux trial: UTI and renal damage

INTRODUCTION

High-grade vesicoureteral reflux (VUR) in children is associated with recurrent urinary tract infection (UTI) and renal damage. Breakthrough UTI despite continuous antibiotic prophylaxis (CAP) during the first years of life is a matter of concern and evokes early intervention. We investigated whether early endoscopic treatment (ET) of VUR grade 4-5 can reduce the risk of UTI recurrence and renal scarring.

MATERIALS AND METHODS

This prospective, randomized, controlled, multicentre, 1-year follow-up trial comprised 77 infants, <8 months of age with VUR grade 4-5 (Table) randomized to CAP (n = 39) or ET (with prophylaxis until resolution) (n = 38). Voiding cystourethrogram, ultrasound, renal scintigraphy, and free voiding observation were performed at study entry and after 1 year. Parenchymal defects were seen in 67 (87%) children at entry, 39 (34 boys, 5 girls) of them characterized as generalized. At follow-up, renal deterioration (new scars or progress in old damaged area) and symptomatic UTIs were reported.

RESULTS

There were 27 recurrent febrile UTIs in 6 (16%) children in the ET group and in 10 (26%) in the CAP group (p = 0.43), in eight (36%) girls and eight (15%) boys (p = 0.039). Successful VUR outcome (VUR 0-2) was seen in 22 (59%) in the ET and eight (21%) in the CAP group (p = 0.0014). Multiple recurrences were only seen in patients with persistent dilating reflux at follow-up (p = 0.019). Deterioration on scintigraphy was seen in eight children (9 kidneys) with no difference between treatment groups (p = 0.48) or sex (p = 0.17). Renal deterioration was associated with high bladder capacity (BC) and large residual volume (PVR) at 1 year (p = 0.0092 and p = 0.041). Six of the eight children with renal deterioration had a recurrent UTI (p = 0.0032). Seven of nine renal units with deterioration were seen in children with persistent VUR 3-5 at follow-up. Univariable logistic regression identified female sex and high PVR as positive predictors for recurrent UTI (p = 0.039 and 0.034) and high PVR tended to predict renal deterioration (p = 0.053).

DISCUSSION

No differences between the treatment groups regarding recurrent UTI and renal deterioration could be found. Increased PVR and female sex were positive predictors for UTI recurrences. VUR grade at follow-up was correlated to UTI recurrence and renal deterioration.

CONCLUSION

This study did not show any difference between ET and CAP in reducing the risk of UTI recurrence or renal deterioration. The rate of VUR resolution was higher in the ET group and VUR grade at follow-up correlated with both UTI recurrence and renal deterioration.

The Swedish Infant High-grade Reflux Trial - Bladder function

INTRODUCTION

It has been suggested that infants with high-grade vesicoureteral reflux (VUR) have lower urinary tract dysfunction (LUTD) that is characterised by large bladder capacity (BC) and increased post-void residual (PVR). However, most of these infants have normal or small BC in early infancy and develop large capacity during the first year of life.

OBJECTIVE

This study aimed to see whether LUTD development during the infant years in children with high-grade VUR could be prevented by early reflux resolution.

MATERIALS AND METHODS

For early VUR intervention, endoscopic treatment (ET) was used in a randomised trial comprising 77 infants (55 boys) aged <8 months with VUR grade 4-5 (n = 30/n = 47); 39 were randomised to antibiotic prophylaxis and 38 to ET. Voiding cystourethrogram, free voiding observation (FVO) and renal scintigraphy were performed at baseline and after 1 year. Bladder capacity and PVR were obtained from FVO. LUTD was defined as a BC of ≥150% of expected and a PVR of ≥20 ml.

RESULTS

There were no differences in bladder function variables seen between the treatment groups, despite significant differences in VUR resolution. Analysing bladder function related to VUR outcome (VUR grade ≤2 vs grade >2), independent of treatment, showed that VUR grade ≤2 was associated with a smaller BC at 1 year (P = 0.050) (a tendency already seen at baseline) and a lower PVR at baseline (P = 0.010). PVR increased from baseline to 1 year (P = 0.037) in children with grade ≤2 VUR (Summary Table). The group with persistent bilateral grade 5 VUR at 1 year had more abnormal bladder variables compared with other study subjects, with a tendency of larger BC (P = 0.057), higher PVR (P = 0.0073) and more LUTD (P = 0.029) at baseline and a larger BC at 1 year (P = 0.016). In explanatory analyses, using logistic regression, a high PVR at baseline was identified as a predictor of VUR grade >2 (P = 0.046), persistent bilateral grade 5 VUR (P = 0.022), recurrent urinary tract infection (P = 0.034), and only a tendency was seen regarding new renal damage (P = 0.053).

CONCLUSION

There was no between-group difference seen in bladder function. In children with VUR resolution at follow-up, independent of treatment, BC decreased, whereas PVR increased. High PVR at baseline was a predictive factor for both non-resolution of high-grade VUR and recurrent urinary tract infection. The results suggest that LUTD cannot be prevented by early VUR resolution, but rather is an important prognostic factor for VUR outcome in both endoscopic and prophylactic treatment.

What is the risk of urinary tract infection in children with antenatally presenting dilating vesico-ureteric reflux?

INTRODUCTION

The incidence of recurrent urinary tract infection (UTI) in children with primary vesico-ureteric reflux (VUR) presenting symptomatically is well documented. The risk of UTI in asymptomatic primary VUR diagnosed on investigation of antenatal hydronephrosis (ANH) is less clear. Paradoxically, several previous studies have suggested a lower risk (1-25%). We ascertain the incidence of UTI amongst antenatally-presenting primary VUR and explore risk factors.

STUDY DESIGN

All patients <16 years managed for primary VUR between 1997 and 2013 were retrospectively reviewed. Patients were identified by searching 'VUR, vesicoureteric reflux' and 'vesico' in the clinical database. Sex, follow up, antibiotic prophylaxis, age at UTI, grade of VUR, radioisotope imaging findings (CRN-congenital reflux nephropathy, NRD-new renal defects), evidence of bladder dysfunction, surgical intervention and resolution were recorded. UTI diagnosis was based on positive urine culture with symptoms including fever. SPSS statistical package and Pearson's Chi-squared test were used to explore significance.

RESULTS

Of 308 patients with primary VUR aged <16 years treated, 242 were diagnosed following presentation with UTI. The remaining 66 (21%) were initially asymptomatic, and VUR was diagnosed on investigation of ANH. All were given prophylaxis from birth. Six months to 16years (median 6years) follow-up was available for 54 (42 males, 12 females). All but two patients had grade III-V VUR (96%), bilaterally in 41 (76%). CRN was evident in 30 (56%; all male) and bladder dysfunction in 12 (22%; 10 males). Twenty-eight patients (52%) developed a UTI. The risk of UTI was 58% in girls, 33% in boys without CRN and 57% in boys with CRN (p = 0.17). Bladder dysfunction was a significant risk factor for UTI (p = 0.03). All 8 (15%; 7 males) with NRD had had a UTI. A single UTI appeared responsible for the majority of NRD (6/8; 75%). UTI occurred in 6/27 (22%) boys after circumcision compared to 17/25 (68%) prior/without circumcision (p < 0.05).

CONCLUSIONS

The incidence of UTI in VUR detected after presentation with ANH was 52%. CRN and bladder dysfunction were risk factors for developing a UTI. Circumcision appears to significantly reduce the risk of infection. Antenatal presentation of primary VUR does not carry a reduced risk of UTI. A single UTI, in half before the age of six months, seemed responsible for the majority of NRD. In boys, the highest risk of UTI is in the first few months of infancy, despite antibiotic prophylaxis, and other interventions, particularly circumcision, should therefore be considered as early as possible.

Predictive risk factors in childhood urinary tract infection, vesicoureteral reflux, and renal scarring management

Approaches to the management of children with urinary tract infection (UTI), vesicoureteral reflux (VUR), and renal scars have been challenged and have become controversial over the past decade. It is difficult to determine when, how, and which patients will benefit from the diagnosis and management of this condition. Therefore, the issues of diagnostic imaging, observation, follow-up, and intervention tend to be decided more on a case-by-case basis, rather than by using an algorithm. Over the past few years, there have been advances in the identification of risk factors that predispose patients with UTI to present with VUR, to develop recurrent UTIs and renal scars, to have deteriorating renal function, to show VUR improvement and/or spontaneous resolution, and to be candidates for and benefit from early surgical intervention.

Diagnostic value of the pediatric lower urinary tract symptom score in children with overactive bladder

PURPOSE

The aims were (1) to assess the pediatric lower urinary tract symptom score (SS) prior to treatment as a means of determining severity of overactive bladder (OAB) and (2) to investigate relationships between SS results and those of standard diagnostic modalities.

MATERIALS AND METHODS

Symptom scores were recorded pre- and 6 months SS for 294 children with OAB unrelated to neurological disorder. Uroflowmetry-electromyography data, total bladder capacity, and a 2-day bladder diary were also recorded, and upper urinary tract deterioration was investigated as indicated. Overactive bladder was treated with standard approaches. No response to treatment was defined as 0-49% reduction in OAB-related symptoms based on SS results. Non-responders underwent additional evaluations as indicated.

RESULTS

Two hundred forty-one patients (97%; mean age 9.8 ± 2.8 years; mean follow-up 11 months; range 6-18 months) completed the study. One hundred thirteen (47%) required ultrasonography (USG), and those with abnormal USG had a significantly higher pre- and 6 months SS (p = 0.016). All non-responders (n = 38; 16%) underwent urodynamics evaluation, 34 underwent spinal magnetic resonance imaging (MRI), 34 underwent voiding cystourethrography (VCUG), and 34 underwent dimercaptosuccinic acid scanning (DMSA). Non-responders with terminal detrusor hyperactivity had significantly lower SS after therapy (p = 0.09). Non-responders with abnormal MRI had higher pre- and 6 months SS than those with normal MRI. Thirteen (38%) of the non-responders who required VCUG had vesicoureteral reflux (VUR), and this subgroup had higher pre-treatment SS (p = 0.030). Seven (21%) of the non-responders who required DMSA had scarring, and all 7 had VUR. The subgroup with scarring had higher pre-treatment SS (p = 0.030).

CONCLUSION

Pediatric OAB patients with high 6 months SS have a higher incidence of additional upper urinary tract pathology. Those with low pre-treatment SS require fewer laboratory tests and other assessments. The SS tool can reduce the number of urodynamics evaluations, and other tests required to diagnose renal damage in children with OAB.

Controversy in urinary tract infection management in children: a review of new data and subsequent changes in guidelines

Controversy and lack of consensus have been encountered in the management of pediatric urinary tract infection (UTI), including its diagnosis, radiological investigations and the use of antibiotic therapy. In this review, we discuss the need for radiological investigations and the extent of their use as well as the need for prophylactic antibiotics in children with UTI and vesicoureteral reflux. Only a small proportion of children with first UTI and no history of antenatal renal abnormalities have clinically important malformations. Renal ultrasound should be performed in febrile infants and young children with UTI; a micturating cystourethrogram should not be performed routinely after the first febrile UTI. Long-term antibiotics appear to reduce the risk of recurrent symptomatic UTI in susceptible children, although the clinical benefit is marginal. Current recommendations encourage performing radiological investigations only in children at risk and discourage routine prophylactic antibiotic use.

Evolution and prognosis value of intrarenal reflux

PURPOSE

The aim of this study was to evaluate the prognostic significance of intrarenal reflux (IRR) regarding urinary tract infection (UTI), renal scarring and spontaneous resolution after 3 years of follow up.

PATIENTS AND METHODS

33 patients (42 refluxing units) with IRR were compared to 27 children (44 refluxing units) with high-grade vesicoureteral reflux (VUR) without IRR (controls) matched for gender, age and VUR grade. All patients received antibiotic prophylaxis during observation and antireflux surgery was performed in children with recurrent UTI. DMSA scan was performed at study entry, and 18 and 36 months.

RESULTS

DMSA scores at entry showed a higher proportion of moderate and severe damage in the IRR group (25/42) compared to the control group (16/44) (Chi squared, P < 0.03). During follow up the incidence of UTI was similar in the two groups, as well as the stability of DMSA scintigraphy and the rate of spontaneous disappearance of the reflux. A similar proportion of patients underwent surgery (18/33 patients with IRR and 13/27 control patients; Chi squared, not significant).

CONCLUSIONS

Under medical management, the prognosis for IRR is not different from high-grade VUR without IRR. The presence of IRR does not justify more aggressive management than a high-grade VUR without IRR.

Endoscopic treatment of vesicoureteral reflux: current practice and the need for multifactorial assessment

Vesicoureteral reflux (VUR) affects around 1% of all children. It carries an increased risk of febrile urinary-tract infections (UTIs) and is associated with impaired renal function. Antibiotic prophylaxis is an established approach to managing the condition, but it does not protect against UTI and encourages bacterial resistance. Ureteral re-implantation (open surgery) is a relatively traumatic procedure typically requiring hospitalization, and there is a risk of significant post-treatment complications. Endoscopic treatment with NASHA/Dx gel (Deflux®) is minimally invasive, well tolerated and provides cure rates approaching those of open surgery: 80-90% in several studies. It has also been shown to be effective in a variety of 'complicated' cases. Thus, endoscopic treatment is generally preferable to open surgery and long-term antibiotic prophylaxis. Non-treatment of VUR is being discussed as an alternative option, although this mainly appears suitable for children with low-grade reflux and normal kidneys. A new approach to managing VUR may be considered, with treatment decisions based not only on the grade of reflux but also on factors such as age, sex, renal scarring and bladder dysfunction. Open surgery would be reserved only for use in the 10-15% of children not responding to endoscopic treatment and those with severe ureteral anomalies.

Vesico-ureteric reflux: using mouse models to understand a common congenital urinary tract defect

Vesico-ureteric reflux (VUR) is a common congenital urinary tract defect in which urine flows retrogradely from the bladder to the kidneys because of an abnormally formed uretero-vesical junction. It is associated with recurrent urinary tract infections, renal hypo/dysplasia, reflux nephropathy, hypertension, and end-stage renal disease. In humans, VUR is genetically and phenotypically heterogeneous, encompassing diverse renal and urinary tract phenotypes. To understand the significance of these phenotypes, we and others have used the mouse as a model organism and this has led to the identification of new candidate genes. Through careful phenotypic analysis of these models, a new understanding of the genetics and biology of VUR is now underway.

Genetics of vesicoureteral reflux

Primary vesicoureteral reflux (VUR) is the most common urological anomaly in children, affecting 1-2% of the pediatric population and 30-40% of children presenting with urinary tract infections (UTIs). Reflux-associated nephropathy is a major cause of childhood hypertension and chronic renal failure. The hereditary and familial nature of VUR is well recognized and several studies have reported that siblings of children with VUR have a higher incidence of reflux than the general pediatric population. Familial clustering of VUR implies that genetic factors have an important role in its pathogenesis, but no single major locus or gene for VUR has yet been identified and most researchers now acknowledge that VUR is genetically heterogeneous. Improvements in genome-scan techniques and continuously increasing knowledge of the genetic basis of VUR should help us to further understand its pathogenesis.

The prognostic impact of an abnormal initial renal ultrasound on early reflux resolution

OBJECTIVE

In a group of children diagnosed with vesicoureteral reflux (VUR) we evaluated renal ultrasound findings, associated findings on renal scan, and prognostic impact on VUR resolution.

METHODS

Medical records were reviewed for children with primary reflux and no history of antenatal hydronephrosis who underwent an initial renal ultrasound. Abnormal renal ultrasound was defined as hydronephrosis or relative difference in renal size ≥1 cm. Reflux resolution was evaluated at 2 years post diagnosis.

RESULTS

In 129 children with VUR (111 girls, 18 boys), 39 (30%) had an abnormal renal ultrasound. Two-year VUR resolution in the abnormal renal ultrasound group was 21% versus 46% in the group with normal renal ultrasound (P = 0.01). Combining grade II and III reflux, an abnormal ultrasound was associated with a statistically significantly lower resolution rate (grade II-III 23% vs 47%, P = 0.049). For children with moderate hydronephrosis, 8/9 (89%) had abnormal initial renal scans and all failed to achieve resolution of reflux at 2 years.

CONCLUSIONS

In this cohort of children with VUR, 30% had abnormalities on renal ultrasound. The presence of moderate hydronephrosis on ultrasound may indicate a high likelihood of abnormality on renal scan and failure to achieve early resolution of VUR.

[Non-neurogenic bladder dysfunction and vesicoureteral reflux in children]

Various types of bladder dysfunction are associated with urinary tract infection, renal damage and vesicoureteral reflux (VUR). In this article the influence of functional bladder disturbances such as detrusor instability (overactive bladder, OAB) and bladder sphincter dyssynergia (dysfunctional voiding), on the resolution of vesicoureteral reflux are reviewed. In summary, it is important to distinguish between children with dysfunctional voiding (increased activity of the pelvic floor during voiding) and those with OAB (detrusor overactivity during filling) because the latter has less effects on VUR.

Non-neurogenic elimination disorders in children

Non-neurogenic elimination disorders cover a wide spectrum of lower urinary tract and bowel dysfunctions, observed in the absence of a neurological background or lower urinary tract malformation. We reviewed conditions responsible for incontinence during bladder filling with normal voiding patterns (such as overactive bladder, giggle incontinence, post-void dribbling), and dysfunctional voiding syndromes. Dysfunctional elimination syndrome usually includes detrusor-sphincter dyscoordination, small-capacity overactive bladder or decompensated large poorly contractile bladder, and large-volume post-micturition residuals, occasionally associated with bowel dysfunction. At the most severe end of the spectrum lies the non-neurogenic neurogenic bladder syndrome, characterized by the association of a severe impairment of the upper urinary tract with a dysfunctional elimination syndrome. It must be emphasized that if the term 'non-neurogenic' relates to the absence of a neurological lesion, it is however conceivable that these conditions actually do have an underlying neurological cause that remains to be identified.

Vesicoureteral reflux associated renal damage: congenital reflux nephropathy and acquired renal scarring

PURPOSE

The pathophysiology, evaluation, description and clinical implications of renal damage associated with vesicoureteral reflux remain controversial. We summarized the current understanding of this important aspect of clinical vesicoureteral reflux.

MATERIALS AND METHODS

We performed a detailed review of the literature on clinical, pathological and experimental data related to congenital vesicoureteral reflux and bladder dynamics. We also reviewed the clinical context and imaging evaluation with underlying experimental data related to post-infectious reflux nephropathy.

RESULTS

Congenital reflux nephropathy is a pattern of impaired renal function and development with renal dysplasia as the most severe but not the only form. Mechanisms of developmental disruption are potentially related to vesicoureteral reflux dynamics during gestation and associated bladder dynamics, which may continue into postnatal life. Acquired renal injury associated with infection is related to particular bacterial and host factors that determine infection virulence, host inflammatory response and tissue recovery. As best seen on dimercapto-succinic acid scan, acute changes may resolve but may also persist as permanent renal scarring. Specific risk factors for acute pyelonephritis and renal scarring in patients with vesicoureteral reflux include higher reflux grade, dysfunctional voiding/elimination, recurrent pyelonephritic episodes and delayed initiation of antibiotic therapy. Low pressure sterile reflux is not a cause of reflux nephropathy.

CONCLUSIONS

Renal damage associated with vesicoureteral reflux may be congenital or acquired and the respective pathophysiological mechanisms are likely different. Congenital damage is often dysplasia, which may be a result of disordered renal development secondary to significant alterations in bladder dynamics. These processes may continue into the newborn period while kidney maturation continues. Recognizing the clinical potential for ongoing effects on renal function and the role of bladder development are important for clinical care. Post-pyelonephritic acquired damage is the result of a complex interaction of host and bacterial factors that leads to acute alterations in renal function, and may lead to permanent renal scarring. Strategies for timely intervention as well as prevention are essential to limit the risk of permanent renal injury, which may predispose to hypertension and renal insufficiency in some patients.

Is the mode of occurrence of vesicoureteral reflux correlated to bladder function and spontaneous resolution?

PURPOSE

To investigate whether mode of occurrence of vesicoureteral reflux (VUR), during micturition (M), during filling without increase in pressure (passive, P) or in response to an overactive contraction (OA), can be explained by differences in bladder function. Also, to study if the mode of occurrence of VUR can predict spontaneous resolution.

MATERIALS AND METHODS

There were 93 infants (68 boys and 25 girls) with VUR (grade III-V) included. Videocystometry was performed at median ages 5, 22 and 32 months registering grade and mode of reflux and bladder function characteristics.

RESULTS

Mode of occurrence of reflux changed with age. During infancy P, OA and M reflux comprised almost equal parts. At follow up, P reflux had increased and both OA and M reflux had decreased. This was partly due to a significantly higher probability of spontaneous resolution for M than P reflux, at 40 months (42 vs 18%). P and M reflux were significantly correlated to bladder function characteristics. P reflux was seen in children with high bladder capacity and occurred early in filling. Other predictors were higher age within the respective group and female sex. M reflux was correlated to lack of residual urine, low bladder capacity and absence of overactivity. Other indicators were male sex and low-grade reflux.

CONCLUSIONS

P and M reflux correlate to different bladder patterns: P with high bladder capacity and M with low bladder capacity and without signs of bladder dysfunction. M seems to be benign with a higher resolution rate.

Endoscopic treatment of vesicoureteral reflux: Current status

Vesicoureteral reflux (VUR) affects around 1% of all children. It carries an increased risk of febrile urinary tract infections (UTIs) and is associated with impaired renal function. Endoscopic treatment with NASHA/Dx gel (dextranomer microspheres in a stabilized hyaluronic acid-based gel of nonanimal origin) is minimally invasive, well tolerated and provides cure rates approaching those of open surgery: approximately 90% in several studies. It has also been shown to be effective in a variety of 'complicated' cases. Endoscopic treatment is therefore considered preferable to open surgery and long-term antibiotic prophylaxis. Nontreatment of VUR is being discussed as an alternative option, whereby children are treated with antibiotics only when UTIs occur. Considering all the available evidence, however, active intervention with endoscopic treatment remains preferable. A new approach to managing VUR may nevertheless be considered, with treatment decisions based not only on the grade of reflux, but also factors such as age, sex, renal scarring, and bladder dysfunction. Open surgery would be reserved for use only in the ( approximately )10% of children not responding to endoscopic treatment, and patients with refluxing primary megaureter.

Bladder dysfunction and vesicoureteral reflux

In this overview the influence of functional bladder disturbances and of its treatment on the resolution of vesicoureteral reflux (VUR) in children is discussed. Historically both bladder dysfunction entities, the overactive bladder (OAB) and the dysfunctional voiding (DV), have been described in conjunction with VUR. Treatment of the dysfunction was also considered to influence spontaneous resolution in a positive way. During the last decades, however, papers have been published which could not support these results. Regarding the OAB, a prospective study with treatment of the bladder overactivity with anticholinergics, did not influence spontaneous resolution rate in children with a dysfunction including also the voiding phase, DV and DES (dysfunctional elimination syndrome), most studies indicate a negative influence on the resolution rate of VUR in children, both before and after the age for bladder control, both with and without treatment. However, a couple of uncontrolled studies indicate that there is a high short-term resolution rate after treatment with flow biofeedback. It should be emphasized that the voiding phase dysfunctions (DV and DES) are more severe than the genuine filling phase dysfunction (OAB), with an increased frequency of UTI and renal damage in the former groups. To be able to answer the question if treatment of bladder dysfunction influence the resolution rate of VUR in children, randomized controlled studies must be performed.

Abnormal renal scans and decreased early resolution of low grade vesicoureteral reflux

PURPOSE

Limited studies suggest a relationship between scarring on renal scan and failure to resolve vesicoureteral reflux. We evaluated the impact of abnormal renal scans on early vesicoureteral reflux resolution.

MATERIALS AND METHODS

The medical records and renal scans were reviewed of children diagnosed with primary reflux between 1988 and 2004. We defined an abnormal renal scan as renal scarring or relative renal function 40% or less. Reflux resolution was noted 1 and 2 years after diagnosis.

RESULTS

Renal scan data were available on 161 children with vesicoureteral reflux, including 127 girls and 34 boys. Relative renal function was 15% or less in 7 children, 16% to 35% in 14, 36% to 40% in 18 and greater than 40% in 122. Of the 161 patients 79 (43%) had an abnormal renal scan, including 37% with grades 1 to 3 reflux. The rate of 2-year reflux resolution in the abnormal and normal renal scan groups was 13% vs 53%. Of children with grades II and III reflux those with an abnormal renal scan were less likely to have reflux resolution compared to those with normal renal scans (23% vs 55% and 4% vs 41, respectively, p <0.05). The same relationship was present at 1 year for grades 2 and 3 (18% vs 49% and 4% vs 30, respectively, p <0.05).

CONCLUSIONS

Abnormal renal scans are an important independent predictor of early failure to resolve vesicoureteral reflux. An abnormal renal scan should be considered when counseling families about the likelihood of early reflux resolution. Performing a renal scan may be indicated in select patients.

Dysplastic kidneys

Dysplastic kidneys are common malformations affecting up to 1 in 1000 of the general population. They are part of the spectrum of Congenital Abnormalities of the Kidney and Urinary Tract (CAKUT) and an increasing number of children are being diagnosed on antenatal ultrasound. In the past, these patients may not have been detected until adulthood following investigation for other illness, or even as incidental findings at post mortem, unless there was severe bilateral dysplasia leading to Potter's sequence or renal failure in childhood. Excluding syndromic cases with defects in other organ systems, features linked to worse prognosis at presentation are: (1) bilateral disease; (2) decreased functional renal mass (which encompasses not just small kidneys but also large ones where cysts replace normal architecture); (3) lower urinary tract obstruction; and (4) anhydramnios or severe oligohydramnios. Dysplasia and renal function are dynamic and can evolve during pregnancy, so repeated assessment is necessary when pathology is expected. Worsening dimensions or decreasing amniotic fluid levels imply poorer prognosis, but there are no proven therapies during pregnancy, though vesicoamniotic shunting may be indicated with obstruction. Postnatal investigations aim to define the anatomy, which helps to estimate risks of infection and kidney function. Management might then involve observation, prophylactic antibiotics, surgery and/or renal support. Risks of renal malignancy and hypertension are low during childhood, but longer-term follow-up is needed, particularly to determine blood pressure and renal function in adulthood and pregnancy. Around 10% of cases have a family history of significant renal/urinary tract malformation. Monogenic causes include mutations in individual genes, such as TCF2/hepatocyte nuclear factor 1ss (HNF1beta), PAX2 and uroplakins, but there are also recent reports of children with compound heterozygote mutations in several renal/urinary tract developmental genes. Effective genetic screening in future may require gene chip or other techniques to assess multiple genes concurrently, but this should not replace a multidisciplinary approach to these often difficult cases.

Postoperative cystography and endoscopic treatment of low-grade vesicoureteral reflux

INTRODUCTION

The endoscopic subureteral injection of tissue-bulking agents has become an established alternative to long-term antibiotic prophylaxis and open surgery with a high success rate, especially for low-grade reflux (>90%). Though it is recognized that a routine postoperative voiding cystourethrography (VCUG) is unnecessary following a ureteroneocystostomy, most teams perform one after an endoscopic treatment.

MATERIALS AND METHODS

In this paper, we report on our experience with the endoscopic correction of vesicoureteral reflux in 72 ureteral units, for whom no routine postoperative cystography was performed.

DISCUSSION

Two children presented with postoperative recurrent febrile urinary tract infections (UTIs), which were not correlated with cystography findings. Postoperative VCUGs after a ureteroneocystostomy are invasive and expose the child to radiation, they are associated with a substantial cost, and most of all, they do not allow the identification of those patients at risk of recurrent febrile UTIs. Further, the endoscopic subureteral injection of tissue-bulking agents have been used for several years, and numerous studies, set in various clinical settings, have since been published, confirming excellent long-term results for low-grade reflux.

CONCLUSIONS

We feel that postoperative cystograms should be reserved for children who present with recurrent UTIs, new sonographic abnormalities, or who were treated for high-grade reflux.

Vesicoureteral reflux

Vesicoureteral reflux (VUR), the retrograde flow of urine from the bladder toward the kidney, is common in young children. About 30% of children with urinary tract infections will be diagnosed with VUR after a voiding cystourethrogram. For most, VUR will resolve spontaneously; 20% to 30% will have further infections, but few will experience long-term renal sequelae. Developmentally, VUR arises from disruption of complex signaling pathways and cellular differentiation. These mechanisms are probably genetically programmed but may be influenced by environmental exposures. Phenotypic expression of VUR is variable, ranging from asymptomatic forms to severe renal parenchymal disease and end-stage disease. VUR is often familial but is genetically heterogeneous with variability in mode of inheritance and in which gene, or the number of genes, that are involved. Numerous genetic studies that explore associations with VUR are available. The relative utility of these for understanding the genetics of VUR is often limited because of small sample size, poor methodology, and a diverse spectrum of patients. Much, if not all, of the renal parenchymal damage associated with end-stage disease is likely to be congenital, which limits the opportunity for intervention to familial cases where risk prediction may be available. Management of children with VUR remains controversial because there is no strong supportive evidence that prophylactic antibiotics or surgical intervention improve outcomes. Furthermore, well-designed genetic epidemiological studies focusing on the severe end of the VUR phenotype may help define the causal pathway and identify modifiable or disease predictive factors.

Bladder dynamics and vesicoureteral reflux: factors associated with idiopathic lower urinary tract dysfunction in children

PURPOSE

The objective of this study was to determine the clinical, demographic, urodynamic and prognostic characteristics related to vesicoureteral reflux among patients with idiopathic lower urinary tract dysfunction.

MATERIALS AND METHODS

We retrospectively reviewed the records of 348 children with idiopathic detrusor overactivity or dysfunctional voiding who had been examined for vesicoureteral reflux between 1995 and 2005 at a university hospital. Demographic, clinical and urodynamic parameters were compared between groups according to the presence, grade, laterality and resolution of vesicoureteral reflux.

RESULTS

Among the 348 patients 8 infants were excluded from statistical analysis and are discussed separately. Among the 340 remaining patients 1 year and older vesicoureteral reflux was documented in 155 (46%), of whom 32% had bilateral reflux. Of the overall cases 60% were grade III or higher. Mean age in the refluxing group (6.5 +/- 2.8 years) was significantly lower than in the nonrefluxing group (7.6 +/- 2.5 years, p <0.001). Continent children presented with a significantly higher rate of vesicoureteral reflux compared to incontinent children (74% vs 42%, p <0.001). Among the patients who had urinary tract infection the presence of reflux increased the rate of renal cortical abnormalities (45% vs 17%, p <0.001). However, among patients who were free of urinary tract infection the presence of reflux was not associated with cortical abnormalities (25% vs 24%, p >0.05). Median maximum filling pressure was higher in the refluxing group compared to the nonrefluxing group (40.0 vs 34.0 cm H(2)O, p <0.001). Detrusor overactivity and dysfunctional voiding showed similar rates for development of vesicoureteral reflux. Reflux was resolved with medical treatment in 40% of the patients. The resolution rate was significantly higher in children with nondilating reflux and initial lower median cystometric bladder capacity.

CONCLUSIONS

Vesicoureteral reflux is associated with daytime incontinence, urinary tract infection, younger age and renal cortical abnormalities among patients with idiopathic lower urinary tract dysfunction. Increased intravesical pressures seem to be the primary factor for inducing reflux in idiopathic lower urinary tract dysfunction. Initial bladder capacity predicts the resolution of reflux.

Part 4: Considerations regarding the medical management of VUR: what have we really learned?

In the treatment of vesicoureteral reflux (VUR), the use of prophylactic antibiotics is most often the first treatment option in children with grades I-IV VUR. Both the overuse and misuse of antimicrobials have accelerated the appearance and spread of antibiotic resistance. There is a lack of controlled studies that address the role and efficacy of prophylactic antibiotic use in the VUR population. Physicians may also be pressured to prescribe antibiotic therapy by patients even in the absence of appropriate indications for use. However, patient reported compliance is often far lower than clinically documented compliance. The associated disadvantages of prophylactic antibiotic use include the development of antimicrobial resistance and patient noncompliance which begs for a re-evaluation of current management patterns of VUR. Considering questionable evidence supporting the use of traditional therapies, new innovations, including endoscopic injection, should be considered as an alternative.

Treatment of Bladder Dysfunction and High Grade Vesicoureteral Reflux Does Not Influence the Spontaneous Resolution Rate

PURPOSE

We investigated whether the treatment of bladder dysfunction in infants with congenital high grade vesicoureteral reflux could influence the spontaneous resolution rate of the reflux and the number of recurrent urinary tract infections.

MATERIALS AND METHODS

A total of 115 infants with high grade vesicoureteral reflux were included in a followup study of bladder function and reflux resolution between 1993 and 1999. The present study deals with 20 of these infants with mainly grade V reflux, most of whom had recurrent urinary tract infections in combination with high post-void residual and high bladder capacity. Treatment with clean intermittent catheterization was instituted during infancy in these 20 patients and continued until a median age of 4 years.

RESULTS

Bladder capacity was high at presentation and at all followup investigations in the clean intermittent catheterization treated group. Moreover, residual urine was high at presentation and especially between ages 1 and 2 years. However, after bladder control was achieved this residual decreased and consisted mainly of reflux urine. In only 1 girl did reflux resolve spontaneously during the 4-year followup period. A total of 18 patients were treated surgically at the end of this period, and clean intermittent catheterization could be stopped a few months later in all but 2. Urinary tract infection recurrences were uncommon after the institution of treatment.

CONCLUSIONS

The treatment of bladder dysfunction characterized by a high capacity bladder with poor emptying in infants with congenital high grade reflux does not influence the rate of spontaneous resolution. On the other hand, the tendency toward recurrent urinary tract infections appears to decrease with treatment.

Renal and Bladder Functional Status at Diagnosis as Predictive Factors for the Outcome of Primary Vesicoureteral Reflux in Children

PURPOSE

We studied the relationship between renal and bladder functional status at diagnosis and spontaneous resolution of reflux in young children with primary vesicoureteral reflux.

MATERIALS AND METHODS

Children with grade III or greater vesicoureteral reflux were recruited for the study. At entry each patient underwent voiding cystourethrogram, renal ultrasound, isotope renogram, and natural filling and conventional filling urodynamic studies. Patients were then divided into 4 groups-group 1 had normal renal and bladder function, group 2 had abnormal renal and normal bladder function, group 3 had normal renal and abnormal bladder function, and group 4 had abnormal renal and bladder function. Correlation between renal and bladder functional status with reflux resolution at a minimum followup of 24 months was evaluated.

RESULTS

A total of 82 patients (mean age 3.8 years) were prospectively evaluated and followed. There were 18 patients (13 males and 5 females) in group 1, 19 (13 and 6) in group 2, 19 (18 and 1) in group 3 and 26 (22 and 4) in group 4. Complete resolution of vesicoureteral reflux occurred in 17 patients (94%) in group 1 and 7 (37%) in group 2. None of the patients from group 3 or group 4 achieved complete vesicoureteral reflux resolution. Reflux grade remained unchanged in 15 patients (79%) in group 3 and 20 (77%) in group 4.

CONCLUSIONS

Resolution of vesicoureteral reflux significantly correlated with renal and bladder functional status at diagnosis. Normal renal and bladder function at diagnosis is highly predictive of complete resolution of vesicoureteral reflux, whereas abnormal renal and bladder function is prognostic for persistence of reflux.

First urinary tract infection in neonates, infants and young children: a comparative study

In an attempt to evaluate first urinary tract infection (UTI) in neonates and infants, we estimated retrospectively in 296 patients (62 neonates and 234 infants) clinical and laboratory findings, occurrence of vesicoureteral reflux (VUR), urinary tract abnormalities and pyelonephritis. First UTI occurred more often in male than female neonates, whereas male and female infants/young children were affected at an equal rate. The pathogens isolated in urine cultures of neonates and infants did not statistically significantly differ (P>0.05); Escherichia coli predominated. Gram-negative bacteria other than E. coli affected boys more often than girls (P=0.0022). Fever was the most frequent symptom. Neonates had lower-grade fever of shorter duration than infants (P<0.05). The incidence of reflux and urinary tract abnormalities did not differ between neonates and infants, male and female neonates and infants (P>0.05). Pyelonephritis affected neonates and infants at an equal rate; it was more prevalent among female patients (P=0.038) and patients with VUR or urinary tract abnormalities other than VUR (P<0.0001). Neonates with reflux were more often affected by Gram-negative bacteria other than E. coli than were neonates without reflux (P=0.0008).

[Evidence-based medicine and vesicoureteral reflux]

Vesicoureteral reflux (VUR) remains one of the most controversial subjects in paediatric urology. Much literature has been published on VUR, making the understanding of this anomaly and its treatments quite opaque. Evidence-Based Medicine (EBM) should be helpful to clarify the various VUR approaches contained in the 6224 titles found on Medline using the keywords "vesicoureteral reflux" and "vesicoureteric reflux". These articles were critically reviewed and graded according to EBM scorings, with regard to their methodological designs. This review of VUR literature suggests that most of our knowledge is based on publications with a low level of evidence, and that EBM lacks arguments to support recommendations for VUR diagnostic and treatment. It appears yet that antenatal dilatation of the urinary tract and symptomatic urinary tract infections (UTI) justify VUR screening. Surgery should be discussed in recurrent UTIs or deterioration of renal function. There is no consensus in case of persistent asymptomatic VUR regarding indication and duration of antibio-prophylaxis, and selection of radical treatment.

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.

Uroplakin III is not a major candidate gene for primary vesicoureteral reflux

Vesicoureteral reflux (VUR) is the retrograde flow of urine from the bladder into the ureter and towards the kidneys. VUR is the most common cause of end stage renal failure in both children and adults and it is a major cause of severe hypertension in children. VUR is seen in approximately 1-2% of newborn Caucasians. Substantial evidence exists that VUR is a genetic disorder. Uroplakins are integral membrane proteins found in the bladder wall. Knockout studies in mice have suggested uroplakin III (UPK3) as a candidate gene for VUR. We have used parametric and nonparametric linkage analysis and tests for association, to investigate this possibility in a cohort of 126 sibling pairs affected with primary VUR. None of the analyses showed any substantial evidence for linkage or association of markers at the UPK3 locus to VUR. Our results do not support a role for UPK3 in primary VUR.

SURGICAL RECONSTRUCTION OF CLOACAL MALFORMATION CAN ALTER BLADDER FUNCTION: A COMPARATIVE STUDY WITH ANORECTAL ANOMALIES

PURPOSE

Patients with cloacal anomalies often suffer bladder dysfunction with recurrent urinary infections and incontinence. We examined the effect of surgical reconstruction by posterior sagittal approach and total urogenital mobilization in either causing or worsening bladder dysfunction.

MATERIALS AND METHODS

Between August 2000 and December 2002 all new patients with cloacal anomalies were prospectively studied to assess the effect of surgical reconstruction by posterior sagittal approach and total urogenital mobilization on bladder function. A comparable group of patients with anorectal malformation (ARM) were studied as comparative controls to assess the effect of posterior sagittal approach without urogenital surgery. Structural anatomy was defined by radiology. Natural filling urodynamics via suprapubic catheter were performed in all infants at 0.2 to 9 months (mean 3) before surgical reconstruction. This assessment was repeated 6 to 24 months (mean 14.8) after surgery, and changes in bladder function were determined by comparative statistics.

RESULTS

A total of 10 patients with cloacal anomalies (5 with short [less than 3 cm] and 5 with long common channel [greater than 3 cm]) and 20 patients with anorectal malformation were consecutively studied. At presentation bladder dysfunction was present in 9 of 10 patients with cloacal anomalies and in 12 of 20 patients with ARM. After surgery there was significant deterioration in bladder function in half of the cloacal group (5 of 10 patients, p = 0.04) and in 1 of 20 patients with ARM (p = 0.7). Of the 5 patients with cloacal anomalies who had deterioration of bladder function urodynamic pattern of detrusor overactivity changed to inadequate (atonic) bladder in 4, all of whom had a long common channel at presentation.

CONCLUSIONS

Patients with cloacal malformation have a high incidence of innate bladder dysfunction. However, surgical reconstruction by total urogenital mobilization can cause further deterioration of bladder function, particularly in the group with a long common channel. Urodynamic assessment is necessary to detect bladder dysfunction in these patients.

SPONTANEOUS RESOLUTION OF HIGH GRADE INFANTILE VESICOURETERAL REFLUX

PURPOSE

We studied the spontaneous resolution rate in a group of infants with high grade vesicoureteral reflux (VUR). The influence of gender, prenatal or postnatal diagnosis, recurrent urinary tract infections (UTIs) and bladder dysfunction on the resolution rate was also evaluated.

MATERIALS AND METHODS

This prospective study comprised 115 infants (80 boys and 35 girls) with high grade VUR (grades III to V). Bilateral reflux was seen in 70% of cases. The majority of patients (71%) were diagnosed after UTI during infancy and only 26% were prenatally diagnosed. Median age at diagnosis was 2.7 months. Patients were followed according to a program of repeat video cystometry and noninvasive 4-hour voiding observations. Median followup was 39 months.

RESULTS

The overall spontaneous resolution rate to grade II or less for all grades was 39% with no difference between boys and girls. However, when comparing the more severe grades IV and V, we found a significantly higher resolution rate in boys during the infant year. No difference in VUR disappearance could be detected when comparing the groups according to presentation, prenatal ultrasound or pyelonephritis. Breakthrough UTIs were seen in 47% of cases despite antibacterial prophylaxis and they significantly correlated with VUR nonresolution. Bladder dysfunction was found in 37% of patients and it also significantly correlated with nonresolution.

CONCLUSIONS

The spontaneous resolution rate for high grade (grades IV and V) congenital VUR was high in boys during the infant year (29%), whereas in girls and boys after the infant year the resolution rate was 9% yearly during followup. Negative prognostic factors for resolution were recurrent UTIs and bladder dysfunction.

A multivariate analysis of dysfunctional elimination syndrome, and its relationships with gender, urinary tract infection and vesicoureteral reflux in children

PURPOSE

We explored and quantified the relationships between dysfunctional elimination syndrome (DES), and gender, urinary tract infection (UTI) and vesicoureteral reflux (VUR) in children.

MATERIALS AND METHODS

Data on 2,759 pediatric patients treated at a referral practice who underwent renal sonography and voiding cystourethrography were summarized. The patients were children with VUR or normal genitourinary anatomy who presented with UTI or dysfunctional voiding and children screened for genitourinary problems such as hematuria, sibling reflux or bedwetting. A multivariate logistic regression approach was used to model and quantify the associations between DES and other pediatric urology factors.

RESULTS

Of the girls 36.0% with unilateral VUR had DES, while 36.1% with bilateral VUR had DES. The corresponding rates for boys were 20.5% and 21.2%. The higher rate of DES in girls was independent of UTI and VUR status. While UTI was not associated with DES in boys or girls without VUR, in patients with VUR and UTI the risk of DES almost doubled (OR 1.97). Reflux alone without UTI was negatively associated with DES in boys (OR 0.50, 95% CI 0.34, 0.73) and girls (OR 0.26, 95% CI 0.19, 0.36).

CONCLUSIONS

Girls had a significantly higher rate of DES than boys in all UTI and VUR subgroups in the current data. UTI significantly impacts the DES occurrence in patients with VUR. No statistically significant difference was detected in the DES rate between the unilateral and bilateral VUR groups, and the reflux group as a whole did not seem to have a higher rate of DES in boys or girls.