Vesicoureteric reflux is not a benign condition

The Effectiveness of Deflux® Treatment for Vesicoureteral Reflux Following Pediatric Renal Transplantation: A Single-Institution Challenging Experience

PURPOSE

To validate the effectiveness of Deflux® treatment for vesicoureteral reflux (VUR) following pediatric renal transplantation (RT), based on our single-institution experience.

METHOD

A retrospective study was conducted using the medical records of pediatric patients who underwent Deflux® treatment for VUR after RT from April 2008 to March 2022.

RESULTS

Sixty-eight pediatric patients underwent RT. VUR was subsequently detected in 22 (32 %) of these patients. Seven of the 22 patients (32 %) underwent Deflux® treatment to avoid renal dysfunction due to urinary infection (UTI). The median age at the time of RT was 4 years (range:2-12). All 7 patients had urinary UTIs before Deflux® treatment. The median estimated glomerular filtration rate (eGFR) before Deflux® treatment was 67 ml/min/1.73 m2 (range:42-138 ml/min/1.73 m2). After Deflux® treatment, VUR was downgraded in three cases (43 %). Four patients (57 %) experienced postoperative UTI, two of who underwent a second Deflux® treatment, one underwent submuscular tunnel reconstruction, and the other one experienced UTI without VUR after 1st Deflux® treatment but did not reoccur. All seven patients continued prophylactic medication after Deflux® treatment, without any history of recurrent UTIs during the observation period after treatment (median 37 months [range 7-86 months]). Furthermore, the eGFRs did not significantly decrease after Deflux® treatment (median eGFR 58 ml/min/1.73 m2 [range:33-99 ml/min/1.73 m2], p > 0.1).

CONCLUSION

Deflux® treatment for VUR after RT is technically challenging because the new ureteral orifice is ventrally anastomosed at the bladder. We believe our results indicate the possibility of reducing the frequency of UTIs and contributing to preservation of the renal function after RT.

TYPE OF STUDY

Retrospective Study.

LEVEL OF EVIDENCE

Level III.

Conflicting views of physicians and surgeons concerning pediatric urinary tract infection: a comparative review

BACKGROUND

A first febrile urinary tract infection (UTI) is a common condition in children, and pathways of management have evolved over time.

OBJECTIVE

To determine the extent to which pediatricians and surgeons differ in their investigation and management of a first febrile UTI, and to evaluate the justifications for any divergence of approach.

MATERIALS AND METHODS

A literature search was conducted for papers addressing investigation and/or management following a first febrile UTI in children published between 2011 and 2021. Searches were conducted on Medline, Embase, and the Cochrane Controlled Trials Register. To be eligible for inclusion, a paper was required to provide recommendations on one or more of the following: ultrasound (US) and voiding cystourethrogram (VCUG), the need for continuous antibiotic prophylaxis and surgery when vesicoureteral reflux (VUR) was detected. The authorship required at least one pediatrician or surgeon. Authorship was categorized as medical, surgical, or combined.

RESULTS

Pediatricians advocated less imaging and intervention and were more inclined to adopt a "watchful-waiting" approach, confident that any significant abnormality, grades IV-V VUR in particular, should be detected following a second febrile UTI. In contrast, surgeons were more likely to recommend imaging to detect VUR (p<0.00001), and antibiotic prophylaxis (p<0.001) and/or surgical correction (p=0.004) if it was detected, concerned that any delay in diagnosis and treatment could place the child at risk of kidney damage. Papers with combined authorship displayed intermediate results.

CONCLUSION

There are two distinct directions in the literature regarding the investigation of an uncomplicated first febrile UTI in a child. In general, when presented with a first febrile UTI in a child, physicians recommend fewer investigations and less treatment, in contrast to surgeons who advocate extensive investigation and aggressive intervention in the event that imaging detects an abnormality. This has the potential to confuse the carers of affected children.

Does STING failure affect short-term graft functions in renal transplant patients: a single-center study

PURPOSE

The aim of the present study was to evaluate outcomes of symptomatic VUR treatment in transplant patients, compare open and endoscopic approaches in terms of graft functions, success rates, complications and recurrent UTIs.

METHODS

67 patients who undergone only STING and STING followed redo UNC due to symptomatic VUR after kidney transplantation were included into the investigation. Patients who had lower urinary tract dysfunctions were excluded from the trial. For 67 patients, baseline and before final surgery and 3rd month creatinine and GFR levels were recorded. Twenty-six of those 67 patients had redo UNC due to failed STING. The data of those patients were compared with the remaining 41 patients who had only STING.

RESULTS

In both groups no statistically significant variations in serum creatinine and GFR levels were detected during follow-up (p > 0.05). Serum levels after STING and in the 3rd month of redo UNC were compared. Although variation was observed in serum creatinine levels and in GFR levels, was not statistically significant (p: 0.59 and p: 0.23). The success rate of STING was %61.1 in 67 patients, and was not significantly different when three VUR grade groups (Grade 3 n:17, Grade 4 n:24, Grade 5 n:36) were compared (p > 0.05).

CONCLUSION

The present study revealed that subureteral endoscopic injection is cost effective and safe for the first-line treatment due to its minimally invasive nature, does not cause delay which leads to deterioration of graft functions. Redo-UNC has acceptable morbidity and complication rates, should be considered when STING is failed.

Prevalence of Risk Factors of Urinary Tract Infections in Infants and Children in Arak, Iran: A Cross-sectional Study

Background: Urinary tract infection (UTI) is one of the most common childhood infections. Urinary tract infections are divided into simple and complex types. If the bladder infection is not treated, it can cause secondary kidney infections, such as acute pyelonephritis, which can lead to kidney scar or permanent kidney damage. A significant percentage of patients of any age are re-infected after antimicrobial treatments during the first six months after the first period of UTI. Objectives: This research aimed to investigate the risk factors affecting UTI in infants and children hospitalized in Arak Amir Kabir Hospital in 2017-2018 to prevent UTI and its secondary complications. Methods: In this cross-sectional study, the data collection tool was a validated questionnaire to gather the child's demographic characteristics, including age, sex, type of nutrition, circumcision, age of circumcision, as well as information about fetal birth weight, chronic maternal diseases such as diabetes and stress, and residence place. The content validation method was used to determine the validity of the checklist, and the test-retest was used for reliability. Data were analyzed by SPSS version 22 software. Results: Sixty four percent of children had the normal ultrasound, while 22% had hydronephrosis and nephrolithiasis on ultrasound. The average thickness and size of the right kidney were 71.75 and 9.11, and those of the left kidney were 9.11 and 9.50, respectively. The most common microorganism was Escherichia coli. Conclusions: Given the importance of prevention and timely diagnosis and treatment of UTI to prevent kidney injuries, it is necessary to find UTI risk factors as the first step to preventing children from secondary kidney injuries.

Relationship between Vesicoureteral Reflux and Glomerular Filtration Rate in Children

Vesicoureteral reflux (VUR) is one of the most common urinary tract anomalies in children and causes renal damage and studies focusing on the effect of VUR on renal function are rare. We recruited 35 primary VUR patients with recurrent urinary tract infection (UTI) and 10 non-VUR patients with recurrent UTI. Contrast-enhanced voiding urosonography (ceVUS) was performed for VUR grading, and renal dynamic imaging was used for evaluating glomerular filtration rate (GFR, mL/min). Standardized GFR (sGFR), namely GFR/BSA (mL·min^-1·m^-2), was calculated based on the body surface area (BSA). Total sGFR (tsGFR, mL·min^-1·m^-2) was obtained from the sum of sGFR on the left and right sides of all the children. The risk of renal regurgitation was equal in the unilateral reflux group. The sGFR of children with grade IV (45.74±18.05 mL·min^-1·m^-2) and grade V (49.67±23.63 mL·min^-1·m^-2) reflux was significantly lower than that in children with grade III (77.69 ±22.21 mL·min^-1·m^-2). The renal function compensation of contralateral non-reflux kidney increased in unilateral reflux group, which was higher than that in the control group and level II, IV and V of reflux group respectively. In VUR group of the same grade, sGFR decreased with the age at diagnosis. In unilateral grade V reflux group, the tsGFR was lower than that in the unilateral grade III reflux group (133.51±48.21 vs. 186.87±53.49 mL·min^-1·m^-2). The patients with VUR of unilateral grade II were significantly older than those with VUR of unilateral grades III and IV. This study indicates that severe VUR is significantly associated with decreased renal function. Therefore, VUR should be diagnosed early and managed individually.

Urinary tract infections in children

Urinary tract infections (UTIs) in children are among the most common bacterial infections in childhood. They are equally common in boys and girls during the first year of life and become more common in girls after the first year of life. Dividing UTIs into three categories; febrile upper UTI (acute pyelonephritis), lower UTI (cystitis), and asymptomatic bacteriuria, is useful for numerous reasons, mainly because it helps to understand the pathophysiology of the infection. A single episode of febrile UTI is often caused by a virulent Escherichia coli strain, whereas recurrent infections and asymptomatic bacteriuria commonly result from urinary tract malformations or bladder disturbances. Treatment of an upper UTI needs to be broad and last for 10 days, a lower UTI only needs to be treated for 3 days, often with a narrow-spectrum antibiotic, and asymptomatic bacteriuria is best left untreated. Investigations of atypical and recurrent episodes of febrile UTI should focus on urinary tract abnormalities, whereas in cases of cystitis and asymptomatic bacteriuria the focus should be on bladder function.

The evaluation of vesicoureteral reflux among children using contrast-enhanced ultrasound: a literature review

INTRODUCTION

Voiding cystourethrogram (VCUG) with fluoroscopy remains the gold standard for detection and evaluation of vesicoureteral reflux (VUR) among children. However, the ionizing radiation exposure remains a concern for this diagnostic modality. Recent studies have proposed using contrast-enhanced ultrasound as an alternative option for VUR screening and follow-up in children. The aim of the study was to review the literature of comparative studies that assessed the diagnostic accuracy of contrast-enhanced ultrasound compared with VCUG.

METHODOLOGY

A systematic literature search was performed on electronic medical literature databases in July 2017. Literature identification, screening, and assessment of eligibility were performed by five reviewers with a pediatric radiologist. Literature was summarized for the study population, contrast used, and ultrasound mode as well as the timing of comparative reference study being performed. The studies were clustered according to the kind of contrast used. Reported diagnostic accuracy was extracted from individual studies and summarized across the included studies using descriptive statistics of median and interquartile range (IQR).

RESULT

A total of 45 comparative studies were identified as eligible for the summary of the literature. Two generations of ultrasound contrast were identified in the available studies (first generation, Levovist and second generation, SonoVue). For the ultrasound studies using the first-generation contrast, the median sensitivity, regardless of the ultrasound mode, was 90.25 (IQR 83.25-97), and the median specificity was 93 (IQR 91.3-95.25). Among studies using the second-generation contrast, the median sensitivity was 86.26 (IQR 81.13-97), and the median specificity was 90.99 (IQR 84-98). No serious adverse events were reported in any of the studies.

CONCLUSION

Overall, this review highlights the application of contrast-enhanced ultrasound for its advantage of no exposure to ionizing radiation and diagnostic accuracy relatively comparable to VCUG in the evaluation of VUR. In addition to the functional evaluation of the VUR, it also provides an anatomic evaluation of the kidneys and bladder with ultrasound imaging. However, one should also note that this alternate procedure is highly operator dependent where diagnostic accuracy is excellent when the expertise is available.

Contrast-enhanced voiding urosonography with intravesical administration of ultrasound contrast agent for the diagnosis of pediatric vesicoureteral reflux

Vesicoureteral reflux (VUR) is one of the most common urinary tract anomalies in children. It has been reported that VUR may be associated with reflux nephropathy. Ultrasound contrast-enhanced voiding urosonography (CeVUS) has become a routine diagnostic method for VUR in a number of European countries; however, it is not widely used in China. The aim of the present study was to analyze the clinical application and evaluate the safety of CeVUS as a diagnostic tool for VUR in children in order to establish a standardized operating procedure for CeVUS in pediatric VUR in China. Between August 2016 and October 2017, 90 children who were susceptible to VUR were admitted into the Pediatric Nephrology Department of Tongji Hospital and underwent CeVUS. The SonoVue second-generation USA contrast agent was administered intravesically via a transurethral bladder catheter at a dose of 1 ml. The occurrence of adverse events was monitored. Urine analysis and culture were performed. A total of 90 children (47 female, 43 male; mean age, 36.6 months) with 178 Pelvi-Ureteral Units (PUUs) underwent CeVUS to screen for VUR. VUR was detected in 44/90 pediatric patients (48.89%) and 65/178 PUUs (36.52%) by CeVUS. The grade distribution of the 65 PUUs with VUS was as follows: Grade I, 3; Grade II, 9; Grade III, 14; Grade IV, 22; and Grade V, 17. The accuracy of CeVUS in the present study were consistent with previous reports. No urethral anomalies were detected and there were no adverse events. CeVUS was demonstrated to be a safe, accurate and reliable imaging technique for detecting VUR in high-risk children, including neonates. Results of the present study indicated that CeVUS can be adopted as the primary screening and follow-up method for pediatric VUR diagnoses in China.

Imaging studies and biomarkers to detect clinically meaningful vesicoureteral reflux

The work-up of a febrile urinary tract infection is generally performed to detect vesicoureteral reflux (VUR) and its possible complications. The imaging modalities most commonly used for this purpose are renal-bladder ultrasound, voiding cystourethrogram and dimercapto-succinic acid scan. These studies each contribute valuable information, but carry individual benefits and limitations that may impact their efficacy. Biochemical markers are not commonly used in pediatric urology to diagnose or differentiate high-risk disease, but this is the emerging frontier, which will hopefully change our approach to VUR in the future. As it becomes more apparent that there is tremendous clinical variation within grades of VUR, the need to distinguish clinically significant from insignificant disease grows. The unfortunate truth about VUR is that recommendations for treatment may be inconsistent. Nuances in clinical decision-making will always exist, but opinions for medical versus surgical intervention should be more standardized, based on risk of injury to the kidney.

Antimicrobial Resistance and Diagnostic Imaging in Infants Younger Than 2 Months Old Hospitalized With a First Febrile Urinary Tract Infection: A Population-based Comparative Study

BACKGROUND

Data on urinary tract infection (UTI) in infants ≤2 months of age are limited. We examined clinical characteristics, antimicrobial resistance, imaging findings and clinical outcomes in infants ≤2 months of age and children 2-24 months of age hospitalized with the first febrile UTI.

METHODS

Children ≤24 months of age hospitalized with their first-diagnosed febrile UTI were prospectively studied. Renal ultrasonography, Tc-dimercaptosuccinic acid scanning and voiding cystourethrography were performed in all children.

RESULTS

Of the 388 children analyzed (255 boys and 133 girls), 61 patients were ≤2 months of age, representing 15.7% of the whole population, whereas 327 patients were 2-24 months of age. Escherichia coli was the predominant bacterium, with similar antimicrobial resistance in the 2 groups, and associated E. coli bacteremia occurred in 9 patients (2.3%). Renal ultrasonography showed abnormal findings in 130 patients (33.5%), but there was no difference in the rate of abnormal findings between the groups. Vesicoureteral reflux (VUR) was present in 130 children (33.5%), including 93 (24%) with grades III-V VUR. VUR was more prevalent in the infants ≤2 months of age (P = 0.007), but there was no difference in the prevalence of grades III-V VUR between the groups. The incidence of renal scarring was 28.6% (111/388), and it did not differ between the groups.

CONCLUSIONS

There are similarities in clinical characteristics, antimicrobial resistance, imaging findings and clinical outcomes after a first UTI between the young infants ≤2 months and children 2-24 months of age. The same guidelines for the diagnosis and management after the first febrile UTI can be applied to children who are ≤24 months of age.

Vesicoureteral refux detection in children: a comparison of the midline-to-orifice distance measurement by ultrasound and voiding urosonography

BACKGROUND

Due to the questionable clinical role of vesicoureteral reflux (VUR) and the search for noninvasive, radiation-free procedures sufficiently reliable to detect VUR, we compared the correlation between the midline-to-orifice distance (MOD) measured by ultrasonography (US) and echo-enhanced voiding urosonography (VUS) for detecting VUR in children. The aim of the study was to determine whether measuring MOD by US could be a reliable predictor of VUR in children.

METHODS

A total of 116 children, aged 0.25-84 months, with 232 potentially refluxing units were investigated simultaneously by measuring the MOD and performing VUS. Indications for cystography were urinary tract infection and follow-up of a previously detected VUR. VUS was performed after the MOD measurement. The results were analyzed with VUS as the reference method.

RESULTS

The MOD was significantly larger in VUR grade III (10.7 mm; p = 0.003) and VUR grade II (9.9 mm; p = 0.001) refluxing units than in non-refluxing units (7.8 mm), even when controlling for the estimated volume/expected maximal capacity (Vest/Vmax) ratio. A MOD cutoff value of 7.4 mm was chosen as a predictor of either the presence or absence of VUR; the sensitivity and specificity of this cutoff measurement for VUR detection were found to be 89 and 24%, respectively.

CONCLUSIONS

Despite the statistically significant difference between the MOD of refluxing versus non-refluxing units identified in our study, the MOD measurement needs further evaluation to determine its potential value as a diagnostic tool for the detection of VUR.

Renal ultrasound and DMSA screening for high-grade vesicoureteral reflux

BACKGROUND

Selection of the appropriate radiologic investigation in a child after first febrile urinary tract infection (UTI) remains a contentious issue. This report investigated the effectiveness of renal bladder ultrasound (RBUS) and late 6 month dimercaptosuccinic acid (DMSA) renal scan in the detection of high-grade vesicoureteral reflux (VUR) after first febrile UTI in infants aged <1 year.

METHODS

A total of 387 infants aged <1 year with first febrile UTI who completed diagnostic follow up consisting of RBUS, voiding cystourethrogram (VCUG) and late 6 month DMSA scan were enrolled in the study. The effectiveness of RBUS and DMSA scan in the detection of high-grade VUR, including cost and benefit were assessed.

RESULTS

Abnormal RBUS was identified in 95 infants (24.5%). VUR was identified on VCUG in 79 (20.4%), of whom eight (2.1%) had high-grade VUR (grade IV-V). Abnormal renal parenchyma was identified on late 6 month DMSA scan in 22 infants (5.7%). The sensitivity of abnormal RBUS and of late 6 month DMSA scan in the prediction of high-grade VUR was 50% and 87.5%, and the proportion of infants who avoided unnecessary VCUG was 75.5% and 94.3%, respectively.

CONCLUSIONS

Fifty percent of high-grade VUR was not identified on RBUS screening after first febrile UTI. Although late 6 month DMSA scan had higher sensitivity in the detection of high-grade VUR, with the added benefit of detection of renal scars, the practical application of this method was limited due to its high cost, radiation exposure and the associated delay in decision making.

Antireflux surgery does not change ongoing renal functional deterioration

AIM

Treatment modalities of vesicoureteral reflux (VUR) consist of antimicrobial prophylaxis and antireflux surgery. In this study, we aimed to determine if antireflux surgery changes the course of renal functional deterioration in children with VUR and urinary tract infections (UTI).

METHODS

Medical files of patients with VUR diagnosed during evaluation for UTI were evaluated retrospectively for gender, age, follow-up period, and renal ultrasonography (US) and serial 99mTc-dimercaptosuccinic acid (99mTc-DMSA) scintigraphy findings. Estimated glomerular filtration rate and urinary protein levels were determined at the initial and last visits, and before the operation in children who had antireflux surgery. The patients were divided into two groups as solely medically treated (Group 1) and both medically and surgically treated (Group 2). Group 2 was further divided as those with stable renal function (Group 2a) and with progressive renal injury (Group 2b).

RESULTS

There were 140 patients (77 female; mean age 51.6 ± 51.9 months). Group 1 and Group 2 included 82 and 58 patients, respectively. In Group 2, the number of patients with the abnormal US, DMSA scintigraphy, and renal function was higher than in Group 1. Recurrent UTI rate was similar, but progressive scarring was more prominent in the antireflux surgery group. In Group 2, 31 patients had a stable renal function (Group 2a) while 27 had progressive deterioration of renal functions (Group 2b). These subgroups were not different with respect to the rate of high-grade VUR, the presence of a renal scar in DMSA, and UTI recurrence. However, the bilateral renal scar was more common in Group 2b.

CONCLUSION

Antireflux surgery does not change the course of ongoing renal injury and renal functional deterioration.

Insignificant impact of VUR on the progression of CKD in children with CAKUT

BACKGROUND

Vesicoureteral reflux (VUR) is associated with an increased risk of kidney disorders. It is unclear whether VUR is associated with progression from chronic kidney disease (CKD) to end-stage kidney disease (ESKD) in children with congenital anomalies of the kidney and urinary tract (CAKUT).

METHODS

We conducted a 3-year follow-up survey of a cohort of 447 children with CKD (stage 3-5). Rates of and risk factors for progression to ESKD were determined using the Kaplan-Meier method and Cox regression respectively.

RESULTS

Congenital anomaly of the kidney and urinary tract was the primary etiology in 278 out of 447 children; 118 (42.4 %) had a history of VUR at the start of the cohort study. There were significantly more boys than girls with VUR, whereas the proportions were similar in children without VUR. The types of urinary anomalies/complications of the two groups were significantly different. Three-year renal survival rates of the groups were not significantly different, irrespective of CKD stage. Age  < 2 years and age after puberty, stage 4 or 5 CKD, and heavy proteinuria, but not history of VUR, were significantly associated with progression to ESKD.

CONCLUSIONS

History of VUR at the start of follow-up was not associated with the progression of stage 3-5 CKD in children with CAKUT.

Primary vesicoureteral reflux: A 26-year experience in a single centre

AIM

To determine the nature of primary vesicoureteral reflux (VUR) and the association of VUR with hydronephrosis and renal damage.

METHODS

The medical records of children ≤ 15 years diagnosed with VUR, attending the Department of Pediatrics, Prince of Songkla University, Thailand between 1987 and 2013 were reviewed. Renal ultrasound and technetium-99m dimercaptosuccinic acid renal scan (DMSA) results were examined to determine the severity of hydronephrosis and renal damage, respectively.

RESULTS

There were 177 boys and 211 girls. 350 (90.2%) were diagnosed following urinary tract infection (UTI). The median (IQR) age at diagnosis of first VUR was 7.6 (4.3-12.2) months in boys and 18.6 (9.0-46.6) months in girls (P < 0.001). Renal ultrasound was performed in 340 patients. Hydronephrosis was found in 105 patients and 135 kidneys and 22.5% VUR kidneys and 11.0% non-VUR kidneys (P = 0.01). The severity of hydronephrosis was associated with VUR grade (44.2% of grades IV and V VUR had hydronephrosis vs 11.9% of grades I-III VUR, P < 0.001). DMSA was performed in 332 patients. Abnormalities were found in 30.1% VUR kidneys and 4.1% non-VUR kidneys (P < 0.001). Abnormal DMSA results were strongly associated with VUR grade (17.8% for VUR grades I-III vs 60.5% for VUR grades IV and V, P < 0.001).

CONCLUSION

Primary VUR in this group was most commonly diagnosed following investigation of UTI and detected during infancy, earlier in boys. Hydronephrosis and renal damage were associated with severity of VUR.

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.

Ureteroneocystostomy in primary vesicoureteral reflux: critical retrospective analysis of factors affecting the postoperative urinary tract infection rates

INTRODUCTION

To determine the parameters affecting the outcome of ureteroneocystostomy (UNC) procedure for vesicoureteral reflux (VUR).

MATERIALS AND METHODS

Data of 398 patients who underwent UNC procedure from 2001 to 2012 were analyzed retrospectively. Different UNC techniques were used according to laterality of reflux and ureteral orifice configuration. Effects of several parameters on outcome were examined. Disappearance of reflux on control VCUG or absence of any kind of UTI/symptoms in patients without control VCUG was considered as clinical improvement.

RESULTS

Mean age at operation was 59.2 ± 39.8 months and follow-up was 25.6 ± 23.3 months. Grade of VUR was 1-2, 3 and 4-5 in 17, 79, 302 patients, respectively. Male to female ratio was 163/235. UNC was performed bilaterally in 235 patients and intravesical approach was used in 373 patients. The frequency of voiding dysfunction, scar on preoperative DMSA, breakthrough infection and previous surgery was 28.4%, 70.7%, 49.3% and 22.4%, respectively. Twelve patients (8.9%) with postoperative contralateral reflux were excluded from the analysis. Overall clinical improvement rate for UNC was 92%. Gender, age at diagnosis and operation, laterality and grade of reflux, mode of presentation, breakthrough infections (BTI) under antibiotic prophylaxis, presence of voiding dysfunction and renal scar, and operation technique did not affect the surgical outcome. However, the clinical improvement rate was lower in patients with a history of previous endoscopic intervention (83.9% vs. 94%). Postoperative UTI rate was 27.2% and factors affecting the occurrence of postoperative UTI were previous failed endoscopic injection on univariate analysis and gender, preoperative BTI, postoperative VUR state, voiding dysfunction on multivariate analysis. Surgery related complication rate was 2% (8/398). These were all low grade complications (blood transfusion in 1, hematoma under incision in 3 and prolonged hospitalization secondary to UTI in 4 patients). In long term, 12 patients are under nephrologic follow-up because of hypertension in 5, increased serum creatinine in 5, proteinuria in 1 and hematuria in 1 patient and all these patients had preoperative scarred kidneys.

CONCLUSIONS

Despite its invasive nature, UNC has a very high success rate with a negligible percent of complications. In our cohort, the only factor that negatively affected the clinical improvement rate was the history of previous antireflux interventions where the predictive factors for postoperative UTI were previous failed endoscopic injection, female gender, preoperative BTI, persistent VUR and voiding dysfunction.

Comparison of procalcitonin and different guidelines for first febrile urinary tract infection in children by imaging

BACKGROUND

We examined the ability of a procalcitonin (PCT) protocol to detect vesicoureteral reflux (VUR) and renal scarring (RS), evaluated procedural costs and radiation burden, and compared four representative guidelines for children with their first febrile urinary tract infection (UTI).

METHODS

Children aged ≤2 years with their first febrile UTI who underwent renal ultrasonography (US), acute and late technetium-99m ((99m)Tc)-dimercaptosuccinic acid scan, and voiding cystourethrography were prospectively studied. The representative guidelines applied in a retrospective simulation included the American Academy of Pediatrics (AAP), National Institute of Clinical Excellence, top-down approach (TDA), and Italian Society of Pediatric Nephrology (ISPN). These were compared in terms of ability to detect abnormalities, procedural costs and radiation.

RESULTS

Of 278 children analyzed, 172 (61.9%) had acute pyelonephritis. There was VUR in 101 (36.3%) children, including 73 (26.3%) with grades III-V VUR. RS was identified in 75 (27.0%) children. To detect VUR, TDA and PCT had the highest sensitivity for grades I-V VUR (80.2%) and III-V VUR (94.5%), respectively, whereas AAP had the highest specificity for I-V VUR (77.4%) and III-V VUR (78.0%), respectively. TDA and PCT had the highest sensitivity (100%) for detecting RS. The highest cost and radiation dose was associated with TDA, whereas AAP had the least expenditure and radiation exposure. By multivariate analysis, PCT and VUR, especially grades III-V, were independent predictors of RS.

CONCLUSIONS

There is no perfect guideline for first febrile UTI children. The PCT protocol has good ability for detecting high-grade VUR and RS. If based on available imaging modalities and reducing cost and radiation burden, clinical suggestions in the AAP guidelines represent a considerable protocol.

Relevance of current guidelines in the management of VUR

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

CONCLUSION

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

Does prompt treatment of urinary tract infection in preschool children prevent renal scarring: mixed retrospective and prospective audits

OBJECTIVE

To test whether active management of urinary tract infections (UTI) in young children by general practitioners can reduce kidney scarring rates.

DESIGN

A comparison of two audits in Newcastle, of children aged <8 years, presenting with UTIs ; a retrospective audit of conventional management during 1992-1995 (1990s) versus a prospective audit of direct access management during 2004-2011 (2000s).

MAIN OUTCOME MEASURES

Kidney scarring rates, and their relationship with time-to-treat.

RESULTS

Children with a first UTI in the 2000s compared to those in the 1990s, were referred younger, were half as likely to have a renal scar (girls OR 0.47, 95% CI 0.29 to 0.76; boys 0.35, 0.16 to 0.81), and were about 12 times more likely to have vesicoureteric reflux without scarring (girls 11.9, 4.3 to 33.5; boys 14.4, 4.3 to 47.6). In the 2000s, general practitioners treated about half the children at first consultation. Children who were treated within 3 days of their symptoms starting were one-third as likely to scar as those whose symptoms lasted longer (0.33, 0.12 to 0.72).

INTERPRETATION

Most kidney defects seen in children after UTIs, are acquired scars, and in Newcastle, active management in primary care has halved this rate.

Observational, medical or surgical management of vesicoureteric reflux

The clinical management of vesicoureteric reflux includes observational, medical and surgical procedures. The choice of management is often a joint decision made between the paediatric nephrologist and urologist. The use of prophylactic antibiotics has become increasingly debated. In recent years, the surgical treatment of reflux (including endoscopic intervention or ureteral reimplantation) has mainly been limited to cases of high-grade reflux. There are several important risk factors that influence the final outcome which need to be identified and treated. The aim of reflux management is no longer to treat imperatively, but rather to avoid renal damage. It is perhaps time to revise the classic saying 'diagnosed reflux - treated reflux' with a new objective 'diagnosed reflux - evaluated reflux'.

CONCLUSION

The management and follow-up of childhood reflux is a joint decision between the paediatric urologist and nephrologist and should be decided on a case-by-case basis.

Autologous fibroblast transplantation at the vesico-ureteral junction as potential reconstructive cell replacement in an animal model

PURPOSE

To evaluate the cellular survival of donor fibroblasts after transplantation at the vesico-ureteral junction (VUJ) and to analyse their potential for reconstructive cell replacement in an animal model as autologous fibroblasts have been used as soft tissue augmentation material for scared and damaged tissue.

METHODS

Muscles biopsies were procured from the lower limb muscles of 4 pigs; cytoplasm of fibroblasts was labelled with nano-sized iron oxide particles. Six weeks after taking of the muscle biopsies, fibroblast transplantation was performed, 3 × 10(6) cells suspended in transplantation medium (in 1-ml syringes) were injected at the VUJ using the modified STING technique. Animals were killed 8 weeks later; seeded fibroblasts were identified using prussian blue staining protocol; histological evaluation and morphological analysis were performed by light microscopy (Mayer's haematoxylin-eosin staining); and bladders were scanned by MRI for visualization and localization of the iron-labelled donor cells.

RESULTS

Donor fibroblast cell colonization and cellular viability at the VUJ was demonstrated by MRI and histochemically indicating cellular uptake of iron particles at the VUJ. It was also evident that transplanted fibroblasts integrate into the extracellular matrix of the distal ureter augmenting ureteral host tissue.

CONCLUSIONS

Labelled implanted autologous fibroblasts were visualized by staining procedure as well as MRI scan demonstrating persistence at the VUJ, suggesting that in vitro expanded fibroblasts survived in vivo after transplantation.

A comparison of echo-enhanced voiding urosonography with X-ray voiding cystourethrography in the first year of life

BACKGROUND

Second-generation echo-enhanced voiding urosonography (VUS) with improved contrast-specific ultrasound (US) techniques is increasingly being used for vesicoureteric reflux (VUR) detection.

AIM

To compare VUS with X-ray voiding cystourethrography (VCUG) and to evaluate the predictive value of pelvicalyceal dilatation for detecting VUR in the first year of life.

MATERIALS AND METHODS

Sixty-six children younger than one were investigated by US, VUS and VCUG. VCUG represented the reference method for VUR detection.

RESULTS

According to VCUG, VUR was present in 16/132 (12%) renal units. VUS confirmed all these and additionally revealed VUR in 26 renal units (all together 42/132 (32%) renal units with VUR). It should be noted that all VUR detected only with VUS and missed by VCUG were of grades II and III. In 27/92 (29%) US normal and in 15/40 (37%) renal units with pelvicalyceal dilatation, VUR was detected by VUS.

CONCLUSION

We believe that VUS could safely replace VCUG in VUR detection in infants, with no regard to the degree of abnormality of the upper urinary tract seen on US. VCUG should be limited only to cases where bladder and/or urethra pathology are suspected.

The impact of vesicoureteral reflux treatment on the incidence of urinary tract infection

Vesicoureteral reflux (VUR) is a heterogeneous disease and its management remains one of the most controversial topics in pediatrics. Management options include surveillance, antibiotics, and surgery. The approval of dextranomer/hyaluronic acid (DHA) as a bulking agent by the Food and Drug Administration was followed by wide acceptance of endoscopic techniques as a major tool in the management of reflux. Pyelonephritis rather than VUR is the most common cause of kidney damage in children. It should be emphasized that the primary goal of diagnosing and treating VUR should be preventing this complication. There are no sufficient data in the literature to address the impact of the different treatment modalities on the incidence of febrile urinary tract infections (feb-UTIs) denoting pyelonephritis, with very few studies evaluating endoscopic treatment in light of this clear and well-defined outcome. The fact that we can correct the anatomy at the vesicoureteral junction with a simple and relatively safe outpatient procedure does not justify offering it to all patients. In this review, we attempt to critically evaluate the available literature pertaining to the impact of different treatment modalities on reducing the incidence of febrile UTIs and kidney damage, with a special emphasis on endoscopic treatment.

Managing children under 36 months of age with febrile urinary tract infection: a new approach

BACKGROUND

Recent guidelines on urinary tract infection (UTI) agree on reducing the number of invasive procedures. None of these has been validated by a long-term study. We describe our 11-years experience in the application of a diagnostic protocol that uses a reduced number of invasive procedures.

METHODS

We reviewed retrospectively the records of 406 children aged between 1 and 36 months at their first UTI. All patients underwent renal ultrasound (RUS). Children with abnormal RUS and those with UTI recurrences underwent voiding cystourethrography (VCUG) and dimercaptosuccinic acid (DMSA) renal scans.

RESULTS

RUS after the first UTI was pathological in 7.4% children; 4.4 % had a second UTI. We performed 48 VCUG: 14 patients (29%) had vesicoureteral reflux (VUR), 12 of which showed an abnormal RUS while 2 had recurrent UTI. After DMSA renal scan renal damage appeared in only 6 of them (12.5%); all these children showed grade IV VUR.

CONCLUSIONS

The application of our guidelines leads to a decrease in invasive examinations without missing any useful diagnoses or compromising the child's health.

Urinary tract infections in children and the risk of ESRF

AIMS

Paediatric guidance on diagnosis and treatment of urinary tract infections (UTIs) has in the past largely focused on identifying children with vesicoureteral reflux, thought to be at greatest risk of renal scarring. This practice has been questioned, specifically the accepted association between UTI and end-stage renal failure (ESRF) through renal scarring. The aim of this article is to ascertain whether we can predict with confidence the true level of risk that a child with a first-time UTI will subsequently develop ESRF attributable to UTI.

METHODS

Using data available from renal registries, an analytical approach based on previous estimates of risk is used to demonstrate the range of plausible estimates of risk that can be generated and levels of uncertainty that surrounds those estimates.

RESULTS

Estimates of the perceived risk of developing ESRF following UTI range from 1/154 to 1/199,900 and are heavily dependent on the assumptions made and the source of data.

CONCLUSION

There is considerable uncertainty in the relationship between childhood UTI and risk of ESRF based on the data currently available. Until further evidence is available, clinicians will continue to debate the risk of UTI and ESRF and consensus opinion will continue to guide management.

Imaging the urinary tract in children with urinary tract infection

AIM

To evaluate whether ultrasonography (US) alone is sufficient in imaging the urinary tract in 1185 children with urinary tract infection (UTI).

METHODS

The reports on US and voiding cystourethrography (VCUG) were reviewed.

RESULTS

Initial US was normal in 861/1185 patients (73%). VCUG revealed abnormal findings in 285/861 (33%), of which grade III-V vesicoureteral reflux (VUR) comprised 97 cases (11%). During follow-up, VUR had resolved in 88/97 (91%) patients: in 50/57 (88%) patients without active treatment for VUR, in 27/29 (93%) with endoscopic and in 11/11 (100%) with open surgery for VUR. During follow-up, 11/97 patients (11%) had developed new renal scarring detectable in US, but no renal impairment occurred. Except for VUR, VCUG showed nonobstructive urethral valves in two infant boys with normal initial US. Thus, in 861 children with normal initial US, 40 patients with grade III-V VUR and two patients with significant nonreflux pathology may have benefited from surgical treatment, giving the total number of possibly missed pathological finding in 42/861 (4.9%) cases if VCUG had not been performed.

CONCLUSION

We suggest that children with UTI could be examined using US alone and to use VCUG only after additional indications.

Radiographic evaluation of children with febrile urinary tract infection: bottom-up, top-down, or none of the above?

The proper algorithm for the radiographic evaluation of children with febrile urinary tract infection (FUTI) is hotly debated. Three studies are commonly administered: renal-bladder ultrasound (RUS), voiding cystourethrogram (VCUG), and dimercapto-succinic acid (DMSA) scan. However, the order in which these tests are obtained depends on the methodology followed: bottom-up or top-down. Each strategy carries advantages and disadvantages, and some groups now advocate even less of a workup (none of the above) due to the current controversies about treatment when abnormalities are diagnosed. New technology is available and still under investigation, but it may help to clarify the interplay between vesicoureteral reflux, renal scarring, and dysfunctional elimination in the future.

Genetic susceptibility to renal scar formation after urinary tract infection: a systematic review and meta-analysis of candidate gene polymorphisms

Identifying patients who may develop renal scarring after urinary tract infections (UTI) remains challenging, as clinical determinants explain only a portion of individual risk. An additional factor that likely affects risk is individual genetic variability. We searched for peer-reviewed articles from 1980 to December 2009 in electronic databases that reported results showing an association between gene polymorphims and renal scaring after UTI. Two independent researchers screened articles using predetermined criteria. Studies were assessed for methodological quality using an aggregate scoring system. The 18 studies ultimately included in the review had investigated 16 polymorphisms in nine genes in association with renal scarring formation after UTI. Based on the predetermined criteria for assessing the quality of the studies, 12 studies (67%) were identified as being of poor quality design. A meta-analysis of cumulative studies showed on association between renal scarring formation after UTI and the angiotensin converting enzyme insertion/deletion polymorphism [ACE I/D; recessive model for D allele; odds ratio (OR) 1.73, 95% confidence interval (CI) 1.09-2.74, P = 0.02] or transforming growth factor (TGF)-β1 c.-509 T > C polymorphism (dominant model for T allele; OR 2.24, 95% CI 1.34-3.76, P = 0.002). However, heterogeneity among studies was large, indicating a strong difference that cannot only be explained by differences in study design. The studies reviewed in this article support a modest involvement of the vasomotor and inflammatory genes in the development of renal scarring after UTIs. This review also shows that only few possible candidate genes have been investigated for an association with renal scarring, raising the hypothesis that some gene polymorphisms may exert their effects through an interaction with as yet uninvestigated factors that may be related to geographic and/or socio-economic differences.

Evidence for and against urinary prophylaxis in vesicoureteral reflux

The role of antimicrobial prophylaxis in vesicoureteral reflux (VUR) has come under increasing scrutiny because of better analytical methods in the published literature, knowledge gained from VUR and renal scars diagnosed without preceding urinary tract infection (UTI), and better renal imaging modalities for diagnosing renal scars. A meta-analysis of the five recent randomized studies with a total of 809 patients with VUR diagnosed after UTI reveals a relative risk of UTI recurrence of 0.82 [95% confidence interval (CI) 0.62-1.08; p = 0.16) with prophylaxis. A meta-analysis of the four studies with a total of 662 patients with UTI with and without VUR evaluated for renal scarring reveals a relative risk of 1.04 (95% CI: 0.84-1.30; p = 0.69), with prophylaxis. However, these observations need to be interpreted with caution because of the limitations with these studies and their heterogeneity for meta-analysis, particularly for renal scarring. More research is needed to validate the role of prophylaxis in VUR diagnosed after UTI, and even more research is warranted to answer the questions regarding antimicrobial prophylaxis across the spectrum of VUR in different clinical settings.

Endoscopic application of dextranomer/hyaluronic acid copolymer in the treatment of vesico-ureteric reflux after renal transplantation

OBJECTIVE

• To evaluate the success of endoscopic dextranomer/hyaluronic acid copolymer (DHAC) application in the treatment of patients with recurrent urinary tract infections (UTIs) and vesico-ureteric reflux (VUR) into the transplanted graft after renal transplantation.

PATIENTS AND METHODS

• Between January 2008 and April 2009, 19 patients with recurrent UTIs presented VUR proven by voiding cystourethrography. • To correct VUR of the transplanted ureter, DHAC was injected endoscopically using hydrodistention technique. • Pre- and postoperative serum creatinine levels, the number of pre- and postoperative UTIs, postoperative complications and reflux resolution rate were recorded. The mean follow-up was 6.5 months.

RESULTS

• The average number of UTIs was reduced significantly from 4.89 (range 2-14) to 1.31 (range 0-4) on pre- and postoperative follow-up, respectively, of 6 months (P < 0.001). The success rate increased from 57.9% after the first injection to 78.9% after the second injection. • The remaining four patients with residual VUR received long-term low dose antibiotic prophylaxis. In total, two (10.5%) patients developed increasing creatinine levels postoperatively as a result of distal ureteral obstruction, and temporary urinary drainage was necessary in both patients.

CONCLUSIONS

• DHAC appears to be an efficient and minimal invasive method for treating VUR after renal transplantation with respect to short-term success. • Further investigation with a larger group of patients and longer follow-up is needed to evaluate the prolonged effect, as well as any potential side effects.

Outcome and management of isolated severe renal pelvis dilatation detected at postnatal screening

The aim of this study was to evaluate the incidence and outcome of isolated severe renal pelvis dilatation (RPD; APD>15<or=20 mm) in an unselected population of 2-month-old infants prospectively followed up for 12-14 months of life. Isolated severe renal pelvis dilatation was detected in 46 of the 11,801 (0.39%) infants screened. Nephro-urological investigations were initiated if RPD persisted, or if urinary tract infection (UTI) occurred during follow-up, and antibiotic therapy was administered only when UTI occurred. At follow-up, RPD persisted in 24 infants. Of these, 8 infants presented with vesico-ureteral reflux (VUR) of grade>or=3 and 16 with ureteropelvic junction obstruction (UPJO). Incidence of UTI was significantly higher (p<0.001) in infants of the study group than in infants of the control group (13.9 vs 2.5%). Our data suggest that isolated severe RPD may be a self-limiting condition and that antibiotic prophylaxis (AP) for the prevention of UTI should not be performed. Considering RDP resolution and the incidence of UTI during follow-up, investigations for uropathy in infants with isolated, severe RPD are justified in persistent cases, or when UTI occurs during follow-up. Careful clinical monitoring for signs of UTI and treatment of each episode of UTI may be sufficient and safe.

Vesicoureteral reflux in children with suspected and proven urinary tract infection

The aim of this study was to estimate the prevalence of vesicoureteral reflux (VUR) and clinically significant ultrasonography (US) abnormalities in a large group of children with proven and suspected urinary tract infection (UTI). The medical reports on renal US and voiding cystouretrographies (VCUG) of 2,036 children were reviewed. Renal US was performed on all children and VCUG on 1,185 children (58%). Based on the urine culture data, the UTI diagnoses were classified into five reliability classes (proven, likely, unlikely, false and no microbial data). The UTI diagnose was considered proven in 583/2036 (28.6%) and false in 145 (7.1%) cases. The prevalence of VUR was similar among those with proven and false UTI [37.4 vs. 34.8%; relative risk (RR) 1.08, 95% confidence intervals (95% CI) 0.7-1.7, P = 0.75] and decreased with increasing age (P = 0.001). Clinically significant US abnormalities occurred in 87/583 (14.9%) cases with proven UTI and significantly less often (11/145, 7.6%) in the false UTI class (RR 1.96, 95% CI 1.1-3.6, P = 0.02). Our finding supports the claim that VUR is not significantly associated to UTI and that its occurrence among children even without UTI is significantly higher than traditional estimates. This challenges the recommendations of routine VCUG after UTI.

Catheter-free methods for vesicoureteric reflux detection: our experience and a critical appraisal of existing data

In recent years, the exact role of vesicoureteric reflux (VUR) in general has become controversial, though in some groups of children the knowledge of the existence or non-existence of VUR is still a very important issue. The number of techniques available for the assessment of VUR is increasing, and a new classification taking into account their real characteristics (direct/indirect, catheter-using/catheter-free, radiation-giving/radiation-free) has been proposed. The purpose of the following review is to evaluate the currently available evidence supporting the use of various catheter-free methods for VUR detection. We believe that as the clinical role of VUR has been questioned, it is even more important for the method of its detection to be user-friendly as regards catheterisation, radiation and availability. There is still no evidence supporting the assertion that any of the catheter-free methods of VUR detection might be the optimal one for any child. However, there are some groups of children who would benefit from using them. New studies using new, catheter-free methods of VUR detection or a combination of two or more of the methods described may prove useful in improving sensitivity and providing additional data on this important issue.

Risk factors for recurrent urinary tract infections in a cohort of patients with primary vesicoureteral reflux

BACKGROUND

Knowledge of risk of urinary tract infection (UTI) recurrence in vesicoureteral reflux (VUR) can help clinicians make therapeutic decisions. The aim of this retrospective cohort study was to identify risk factors associated with recurrent urinary tract infection in children with VUR. In addition, a risk score that might predict the chance of UTI recurrence was also proposed.

METHODS

Between 1970 and 2007, 740 patients were diagnosed with VUR and were systematically followed up at a single tertiary Renal Unit. Recurrent UTI was defined as more than 1 episode during follow-up. A binary logistic regression model was applied to identify variables independently associated with recurrent UTIs.

RESULTS

During follow-up, information was obtained on 58,856 person-months. Recurrent UTIs occurred in 120 (16.2%) patients. The overall incidence rate of UTI was 8.4 episodes per 1000 person-months (95% CI, 7.7, 9.2). After adjustment by multivariable analysis, 5 variables were independent predictors of recurrent UTI: UTI as clinical presentation, age < 6 months, female gender, dysfunctional elimination syndrome, and severe grade of reflux. The risk for recurrent UTI was classified as low in 24% of children, medium in 42%, and high in 34%. UTI incidence rates per 1000 person-months were 4.3 (95% CI, 3.2, 5.6), 7.9 (95% CI, 6.7, 9.1), and 11.3 (95% CI, 9.9, 12.8) for low-, medium-, and high-risk groups, respectively.

CONCLUSION

The prediction model of recurrent UTI allows an early recognition of patients at risk for long-term morbidity and might contribute to the formulation of therapeutic strategies.

Urinary tract infections: to prophylaxis or not to prophylaxis?

Urinary tract infections, with or without reflux, are the most frequent reason for long-term antibacterial prophylaxis in infants and children. When one is considering the use of prophylaxis in these children, what is clear from existing published data? Up to 2006 there were a small number of poor quality studies, with no reliable evidence of the effectiveness of antibiotics in preventing recurrent symptomatic urinary tract infections (UTIs). Since then, four randomised controlled studies, to assess the benefits, or lack thereof, of antibiotic prophylaxis, have been published. None has demonstrated a clear benefit. The following conclusions can be drawn: antibiotic prophylaxis is not indicated for children following a first febrile UTI if no or mild grade I or II reflux is present; for higher grade reflux there is no definite conclusion.