Clinical course of 735 children and adolescents with primary vesicoureteral reflux

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

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

Vesicoureteral reflux is associated with increased risk of chronic kidney disease: A nationwide cohort study

The association between vesicoureteral reflux (VUR) and chronic kidney disease (CKD) risk remains unestablished. We investigated the incidence of CKD in children with VUR in Taiwan and evaluated whether they had a higher risk of CKD than the general population. A nationwide population-based cohort study was conducted among children with VUR identified using Taiwan's National Health Insurance Research Database from 2000 to 2013. VUR was defined according to the International Classification of Diseases, Ninth Revision, Clinical Modification codes. We identified the children with VUR and randomly selected comparison children according to a 1:1 ratio, matching them by age, gender, index year and comorbidity using data from the National Health Insurance Research Database. In total, 8648 children with VUR and 8648 comparison children were included. All children were followed from the study date until a diagnosis of CKD, termination of insurance, or the end of 2013. Cox proportional hazards regressions were performed to compare the hazard ratios for CKD between the 2 cohorts. Incident cases of CKD were identified. After adjustment for potential confounders, the study cohort was independently associated with a higher risk of CKD (adjusted hazard ratio, 3.78; 95% confidence interval, 2.10-7.18). This population-based cohort study indicated that children with VUR have a higher risk of CKD than those without VUR.

Primary Vesicoureteral Reflux and Renal Scarring

Vesicoureteral reflux (VUR) is the commonest congenital anomaly of urinary tract in children. It is mostly diagnosed after a urinary tract infection or during evaluation for congenital anomalies of the kidney and urinary tract. High-grade VUR, recurrent pyelonephritis, and delayed initiation of antibiotic treatment are important risk factors for renal scarring. The management of VUR depends on multiple factors and may include surveillance only or antimicrobial prophylaxis; very few patients with VUR need surgical correction. Patients with renal scarring should be monitored for hypertension and those with significant scarring should also be monitored for proteinuria and chronic kidney disease.

Risk factors for renal scarring and clinical morbidity in children with high-grade and low-grade primary vesicoureteral reflux

INTRODUCTION

Primary vesicoureteral reflux (VUR) is associated with urinary tract infections (UTIs) and renal damage. However, the importance of early diagnosis of VUR has been questioned. Moreover, most studies have few patients with high-grade VUR. Hence, we retrospectively analyzed a large cohort of patients with primary high-grade and low-grade VUR and assessed risk factors for renal damage and clinical morbidity.

MATERIAL AND METHODS

We included patients (<18 years) at diagnosis with low-grade (1-3) or high-grade (4-5) primary VUR and noted their clinical history and presence of hypertension, low eGFR (<60ml/in/1.73 m²), renal scarring (focal or generalised) and reduced differential renal function (DRF; <45%). Risk factors were assessed (in patients and renal units) by logistic regression and generalised estimating equation.

RESULTS

Of 399 primary VUR patients, 255 (64%) had high-grade VUR. Indications for voiding cystourethrogram were recurrent UTI (38%), first UTI (28%) and antenatal hydronephrosis (17%). At diagnosis, 252 (65%) had renal scars (focal in 170 [44%], generalised in 82 [21%]), and 188 (47%) had reduced DRF. High-grade VUR patients were more likely than low-grade VUR patients to have renal scarring (75% vs. 49%, p < 0.01), low eGFR (23% vs. 13%, p = 0.04) and significant hypertension (26% vs. 13%, p = 0.02). High-grade VUR was associated with generalised scars (odds ratio [OR] 11, p < 0.001), focal scars (OR 3.1, p < 0.001) and reduced DRF (OR 2.3, p < 0.001) shown in the table. Male sex was a risk factor for generalised scars (OR 2.3, p = 0.005). Focal scars were associated with recurrent UTIs (OR = 1.8, p = 0.004) and reduced DRF (OR 1.4, p = 0.027). Patients with multiple focal scars were diagnosed at an older age (2 years [1,4] than those with single scars (1.5 years [1,4] or no scars (1 year [0, 3]), p = 0.04).

DISCUSSION

The prevalence of renal damage and clinical morbidity at VUR diagnosis was higher than other studies. High-grade VUR patients had a greater prevalence of renal damage, low eGFR and hypertension than low-grade VUR patients and was a risk factor for focal scars, generalised scars and reduced DRF. Focal scars were independently associated with recurrent UTI. Those with multiple scars were diagnosed later than those with single scars or no scars.

CONCLUSIONS

High-grade VUR was associated with renal damage and clinical morbidity. Our study highlights the importance of diagnosing VUR early to identify patients who may warrant long-term follow-up and intervention to minimize morbidity.

Urinary tract infection in pediatrics: an overview

OBJECTIVE

This review aimed to provide a critical overview on the pathogenesis, clinical findings, diagnosis, imaging investigation, treatment, chemoprophylaxis, and complications of urinary tract infection in pediatric patients.

SOURCE OF DATA

Data were obtained independently by two authors, who carried out a comprehensive and non-systematic search in public databases.

SUMMARY OF FINDINGS

Urinary tract infection is the most common bacterial infection in children. Urinary tract infection in pediatric patients can be the early clinical manifestation of congenital anomalies of the kidney and urinary tract (CAKUT) or be related to bladder dysfunctions. E. coli is responsible for 80-90% of community-acquired acute pyelonephritis episodes, especially in children. Bacterial virulence factors and the innate host immune systems may contribute to the occurrence and severity of urinary tract infection. The clinical presentation of urinary tract infections in children is highly heterogeneous, with symptoms that can be quite obscure. Urine culture is still the gold standard for diagnosing urinary tract infection and methods of urine collection in individual centers should be determined based on the accuracy of voided specimens. The debate on the ideal imaging protocol is still ongoing and there is tendency of less use of prophylaxis. Alternative measures and management of risk factors for recurrent urinary tract infection should be emphasized. However, in selected patients, prophylaxis can protect from recurrent urinary tract infection and long-term consequences. According to population-based studies, hypertension and chronic kidney disease are rarely associated with urinary tract infection.

CONCLUSION

Many aspects regarding urinary tract infection in children are still matters of debate, especially imaging investigation and indication of antibiotic prophylaxis. Further longitudinal studies are needed to establish tailored approach of urinary tract infection in childhood.

The long-term prognosis of nephropathy in operated reflux

OBJECTIVE

To investigate the postoperative long-term prognosis and the factors predicting the renal function of patients with reflux nephropathy. As the serum creatinine (s-Cr) level tends to increase during infancy, the degree of reflux and renal parenchymal damage are thought to be more important factors in pediatric patients than in older patients.

MATERIALS AND METHODS

This study examined s-Cr, urinary protein, and blood pressure of patients who underwent anti-reflux surgery 10 years before. It also calculated the postoperative estimated glomerular filtration rate (eGFR) and examined the correlation between the eGFR and preoperative factors (age, gender, number of urinary tract infections [UTIs], primary diagnosis, reflux grade, percentage of dimercaptosuccinic acid uptake, degree of renal parenchymal damage, s-Cr abnormality, proteinuria, and hypertension), and analyzed the factors associated with the long-term prognosis.

RESULTS

The study population was 51 infants (37 boys and 14 girls). The mean age of the patients before surgery and at the follow-up examination was 3.41 ± 3.61 and 14.63 ± 3.74 years, respectively. After surgery, the s-Cr, urinary protein, and blood pressure values showed (44.7%, 26.7%, and 18.2%, respectively) were abnormal. The postoperative eGFR was a mean 90.27 ± 20.42 ml/min/1.73 m² and primary correlated with an older age (P = 0.0361), no UTI at the primary diagnosis (P = 0.0044), reflux grade ≥8 (P = 0.0180), degree of renal parenchymal damage (group ≥2b, P < 0.0001), s-Cr abnormality (P < 0.0001), and proteinuria (P = 0.0001) at baseline. A total of 20 patients had chronic kidney disease (CKD; Fig. 1). The multiple regression analysis of these factors revealed that an older age (P = 0.0021), reflux grade ≥8 (P = 0.0134), and degree of renal parenchymal damage (group ≥2b, P < 0.0001) were significantly associated with the long-term postoperative prognosis of reflux nephropathy. Using these three factors, this study derived a multiple regression equation estimating eGFR in the 10th year after surgery (Fig. 1).

DISCUSSION

In this study, severe vesico-ureteral reflux (reflux grade ≥8) and severe renal parenchymal damage (group ≥2b) were associated with a long-term decrease in the eGFR. In particular, renal parenchymal damage was closely correlated with the postoperative eGFR; thus, this was clearly a critical factor. The age at surgery showed a better correlation with the postoperative eGFR in the multiple regression analysis; thus, age was regarded as an independent prognostic factor.

CONCLUSIONS

The age, reflux grade, and degree of renal parenchymal damage at baseline were factors that affected the long-term postoperative prognosis of reflux nephropathy. Patients with high-grade reflux and severe renal parenchymal damage were more likely to show a reduced CKD level at 10 years after anti-reflux surgery.

Urinary C-megalin for screening of renal scarring in children after febrile urinary tract infection

BackgroundFebrile urinary tract infection (fUTI) in children may cause renal scarring. This study aimed to investigate the usefulness of urinary biomarkers for diagnosing renal scarring after fUTI.MethodsThirty-seven children (median age: 1.36 years, range: 0.52-12.17 years, 25 boys) with a history of fUTI, who underwent renal scintigraphy for 4 months or longer after the last episode of fUTI, were analyzed. A spot urine sample was obtained on the day of renal scintigraphy to measure levels of total protein, N-acetyl-β-D-glucosaminidase (NAG), β₂-microglobulin (BMG), neutrophil gelatinase-associated lipocalin (NGAL), liver-type fatty acid binding protein (L-FABP), and C-megalin (full-length megalin). Results were corrected for urinary creatinine (Cr) and compared between the group with renal scarring (n=23) and that without scarring (n=14). Urinary levels of C-megalin were also measured in healthy control subjects.ResultsNo significant differences in total protein, NGAL, L-FABP, NAG, and BMG levels were found between the groups. However, C-megalin levels were significantly higher in the renal scarring group than in the non-renal scarring group and healthy controls (P<0.001). A cutoff value of 6.5 pmol/nmol of urinary C-megalin/Cr yielded 73.9% of specificity and 92.9% of sensitivity.ConclusionUrinary C-megalin is useful for diagnosing renal scarring caused by fUTI.

Urinary excretion of EGF and MCP-1 in children with vesicoureteral reflux

Purpose

The aim of this study was to investigate the urinary concentration of epidermal growth factor (EGF) and monocyte chemotactic protein-1 (MCP-1) as reflux nephropathy (RN) biomarkers before and after endoscopic treatment of moderate to severe vesico-ureteral reflux (VUR).

Materials and methods

A prospective study was carried out on 72 children with moderate to severe VUR. All patients underwent endoscopic treatment using Macroplastique® or Deflux®. Vesico-ureteral reflux resolution was tested by post-operative voiding cystourethrography after 3 months and 2 years. Follow-up urinary samples were collected at that time. Control samples were taken from healthy children with no clinical evidence of renal and bladder disease and no history of UTI.

Results

In VUR patients, pre-operative urinary EGF levels had a down-regulation when compared to controls. Following successful VUR repair, urinary EGF levels of VUR children progressively increased only at long term follow-up but without returning to normal levels. Urinary MCP-1 levels were highly expressed in pre-operative samples and decreased markedly during early post-operative measurements. Urinary MCP-1 levels did not further decreased in late post-operative follow-up. In fact, these levels remained significantly higher when compared to controls.

Conclusions

Urinary levels of EGF and MCP-1 may become useful markers for monitoring the response to surgical treatment in VUR patients. Although endoscopic VUR treatment is effective in reducing the inflammatory response, the persistence of significant abnormal levels of inflammatory cytokines (such as urinary MCP-1) at long term follow-up suggests that surgery alone may not completely treat the chronic renal inflammation evidenced in these children.

Clinical Course of Children and Adolescents with Primary Vesicoureteral Reflux: A retrospective study of 958 patients

Introduction. Vesicoureteral reflux (VUR) is the most common pediatric urologic abnormality and since it can predispose to urinary tract infection and resultant kidney scar it is an important issue in pediatric nephrourology. Methods. A retrospective chart review and follow-up of 958 patients with primary VUR was performed in the Children’s Medical Center, Tehran, Iran. Children with primary vesicoureteral reflux were included in the study and these parameters were studied: age, sex, clinical presentation, VUR grade, sonographic findings, DMSA changes, treatment modality (medical, surgical or endoscopic) and response to treatment, hypertension (presence/absence), urinary tract infection recurrence and development of new kidney scars in patients under medical treatment. Results. VUR was more prevalent in girls. Sonography was unable to detect VUR in many cases. Presence of renal scars was strongly associated with degree of reflux. Medical management was effective in a substantial percentage of patients and they experienced full resolution of reflux. This was especially true for lower degrees of VUR. 17.6% of patients developed new kidney scars on followup which was associated with higher degrees of VUR. Hypertension and breakthrough urinary tract infection was an uncommon finding in our patients. Conclusion. Medical management, which means using prophylactic antibiotics for prevention of urinary tract infection, is effective in many cases of VUR especially in cases with lower degrees of VUR. Surgical and endoscopic procedures must be reserved for patients with higher degrees of VUR unresponsive to conservative management or in whom new scars may develop.

Voiding cystourethrogram: How much should we be selective?

OBJECTIVE

In this study, we examined the patients' characteristics, who underwent voiding cystourethrography (VCUG), in order to determine any selectivity for indication of this invasive method.

MATERIAL AND METHODS

After exclusion of indications of neurogenic bladder or antenatal hydronephrosis and control VCUGs, 159 VCUGs performed in our clinic within one year were evaluated. Patients are divided into three groups accoding to age. Clinical characteristic and findings of renal ultrasonography (US) and renal scintigraphy were examined.

RESULTS

Vesicoureteral reflux (VUR) was detected in 61 (38.3%) of 159 patients who underwent cystourethrographic examinations, in 45.8% of the patients with a history of recurrent urinary tract infection (UTI), in 22.0% of the patients with pathological urinary system US without history of recurrent UTI. High-grade reflux rate was significantly more frequent in renal units with pathological US findings. Severe scar was significantly more frequent in renal units with high-grade reflux when compared to renal units without reflux and those with low-grade reflux. Predictive values of recurrent UTI, scarring status and pathological US for VUR were separately analyzed and seen that likelihood of indicating VUR was increased when all 3 risk factors were assessed together.

CONCLUSION

Vesicoureteral reflux is a problem in which diagnostic process and management strategy should have to be considered in individualized manner for each patient. Before prescribing invasive VCUG, imaging urinary system by US and scintigraphy and determining whether there is recurrent UTI will improve selectivity and success of VCUG.

Urinary tract infection in small children: the evolution of renal damage over time

BACKGROUND

Our objective was to analyze the evolution of kidney damage over time in small children with urinary tract infection (UTI) and factors associated with progression of renal damage.

METHODS

From a cohort of 1003 children <2 years of age with first-time UTI, a retrospective analysis of 103 children was done. Children were selected because of renal damage at index ^99mTc-dimercaptosuccinic acid (DMSA) scintigraphy at least 3 months after UTI, and a late DMSA scan was performed after at least 2 years. Damage was classified as progression when there was a decline in differential renal function (DRF) by ≥4%, as regression when there was complete or partial resolution of uptake defects.

RESULTS

Of 103 children, 20 showed progression, 20 regression, and 63 remained unchanged. There were no differences between groups regarding gender or age. In the progression group, 16/20 (80%) children had vesicoureteral reflux (VUR) grade III-V and 13 (65%) had recurrent UTI. In multivariable regression analysis, both VUR grade III-V and recurrent UTI were associated with progression. In the regression group, 16/20 (80%) had no VUR or grade I-II, and two (10%) had recurrent UTI.

CONCLUSIONS

Most small children with febrile UTI do not develop renal damage and if they do the majority remain unchanged or regress over time. However, up to one-fifth of children with renal damage diagnosed after UTI are at risk of renal deterioration. These children are characterized by the presence of VUR grades III-V and recurrent febrile UTI and may benefit from follow-up.

Genetic Variations in Vesicoureteral Reflux Sequelae

Urinary tract infections (UTI) are a common condition in children. Vesicoureteral reflux (VUR) represents a common associated condition with childhood UTI. UTI susceptibility appears to have a genetic component based on family and UTI cohort studies. Targeted analysis of innate immune system genetic variations indicate that these variations are important in UTI susceptibility. In this overview, we discuss how current cohorts and genetic strategies can be implemented to discover new susceptibility loci in patients with UTI.

Vesicoureteric reflux in children

Vesicoureteric reflux is defined as the retrograde passage of urine from the bladder into one or both ureters and often up to the kidneys, and mainly affects babies and infants. In severe cases dilatation of the ureter, renal pelvis, and calyces might be seen. Traditionally it was thought that only a low percentage of children have vesicoureteric reflux, but studies have suggested as many as 25-40% are affected. Guidelines recommend that the number of investigations for vesicoureteric reflux in children who have had a febrile urinary tract infection be reduced, but this approach is controversial. The recommendations also suggest that prophylactic antibiotics and surgery should be avoided in children with non-severe vesicoureteric reflux. In this Seminar I present data on the management of children with vesicoureteric reflux and give suggestions on how to navigate this difficult area.

Evaluation and management of recurrent urinary tract infections in children: state of the art

Urinary tract infections (UTIs) represent an important cause of febrile illness in young children and can lead to renal scarring and kidney failure. However, diagnosis and treatment of recurrent UTI in children is an area of some controversy. Guidelines from the American Academy of Pediatrics, National Institute for Health and Clinical Excellence and European Society of Paediatric Radiology differ from each other in terms of the diagnostic algorithm to be followed. Treatment of vesicoureteral reflux and antibiotic prophylaxis for prevention of recurrent UTI are also areas of considerable debate. In this review, we collate and appraise recently published literature in order to formulate evidence-based guidance for the diagnosis and treatment of recurrent UTI in children.

Ultrastructural and immunohistopathological evaluation of intravesical ureters via electron and light microscopy in children with vesicoureteral reflux

PURPOSE

We used immunohistochemical methods and transmission electron microscopy to investigate the cytokine profiles and ultrastructural changes in the ureterovesical junction of children with primary vesicoureteral reflux.

MATERIALS AND METHODS

A total of 39 distal intravesical ureters were obtained from 23 children who underwent ureteroneocystostomy for primary vesicoureteral reflux. Ureteral wall smooth muscle organization and transforming growth factor-β1, vascular endothelial growth factor and CD34 were evaluated immunohistochemically and compared to controls, which consisted of 10 age matched autopsy specimens. Ultrastructural evaluations and morphological descriptions were performed semiquantitatively and compared to the published data.

RESULTS

Of the patients 6 (26%) were male and 17 (74%) were female, and mean ± SD age was 73.2 ± 34.3 months (range 12 to 168). There was no correlation between reflux grade and age (p = 0.39). Smooth muscle disorganization score differed significantly between patients with intravesical ureters and controls (p = 0.01). Transforming growth factor-β1 levels were significantly higher (p = 0.001) and vascular endothelial growth factor levels and microvessel densities were significantly lower in the patients with reflux compared to controls (both p <0.001). Vascular endothelial growth factor, CD34 and transforming growth factor-β1 levels did not correlate with reflux grades (p = 0.84, p = 0.76 and p = 0.10, respectively). Urothelium, lamina propria and tunica adventitia appeared normal in the specimens for all grades of vesicoureteral reflux using transmission electron microscopy. Damage was observed in the muscular layers of the ureterovesical junction, especially in patients with grade IV or V reflux.

CONCLUSIONS

Primary refluxing ureters exhibit immunohistopathological abnormalities compared to normal ureters irrespective of reflux grade, and ultrastructural changes are especially severe in cases of high grade reflux. These abnormalities can hinder the normal ureteral valve mechanism, and may lead to reflux due to smooth muscle dysfunction and microvascular alterations.

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.

Risk factors for renal scarring and deterioration of renal function in primary vesico-ureteral reflux children: a long-term follow-up retrospective cohort study

BACKGROUND AND PURPOSE

The aim was to identify the risk factors for renal scarring and deteriorating renal function in children with primary vesico-ureteral reflux (VUR).

MATERIALS AND METHODS

Patients with primary VUR admitted to the National Cheng Kung University Hospital were retrospectively analyzed. The outcomes were renal scarring, assessed by technetium-99 m dimercaptosuccinic acid scanning, and renal function, assessed by estimated glomerular filtration rate. Univariate and multivariate models were applied to identify the corresponding independent predictors.

RESULTS

A total of 173 patients with primary VUR were recruited. The median age of VUR diagnosis was 10.0 months (IQR: 4.0-43.0 months). After adjusting for confounding factors, it was found that older age of VUR diagnosis (≥5 years vs. <1 year, adjusted OR = 2.78, 95% CI = 1.00-7.70, p = 0.049), higher grade of VUR (high grade [IV-V] vs. none, adjusted OR = 15.17, 95% CI = 5.33-43.19, p<0.0001; low grade [I-III] vs. none, adjusted OR = 5.72, 95% CI = 2.43-13.45, p<0.0001), and higher number of UTI (≥2 vs. 0, adjusted OR = 3.21, 95% CI = 1.06-9.76, p = 0.039) were risk factors for renal scarring, whereas a younger age of VUR diagnosis (≥5 years vs. <1 year, adjusted HR = 0.16, 95% CI: 0.05-0.51, p = 0.002), renal scarring (yes vs. no, adjusted HR = 3.66, 95% CI: 1.32-10.16, p = 0.013), and APN (yes vs. no, adjusted HR = 3.10, 95% CI: 1.05-9.14, p = 0.041) were risk factors for developing chronic kidney disease stage 2 or higher.

CONCLUSIONS

Our findings expand on the current knowledge of risk factors for renal scarring and deteriorating renal function, and this information can be used to modify the management and treatment of VUR.

The association of adult kidney size with childhood vesicoureteral reflux

BACKGROUND

We used ultrasound to measure kidney volumes in adults with a history of childhood vesicoureteral reflux (VUR) and assessed whether total renal volume, small kidney size or the thickness of the upper pole correlated with renal function or hypertension.

METHODS

The kidneys of 123 adults were studied by ultrasound, calculating their volumes using an ellipsoid formula normalised to body surface area (Vol(N)). The thickness of the upper pole parenchyma and the number of small kidneys (<80% of normal volume) were recorded. Blood pressure measurements and laboratory tests were also performed.

RESULTS

Kidneys with a history of VUR were 12% smaller than those without known VUR (p < 0.05), and those with prior dilating VUR were 16% smaller than those with non-dilating VUR (p < 0.05). There was a moderate correlation (r = 0.42, p < 0.05) between total Vol(N) and GFR values in the total patient series. Thirteen percent of the patients had a moderate decrease in kidney function. The occurrence of hypertension and proteinuria was not affected by either kidney size or a thin upper pole.

CONCLUSIONS

Total Vol(N) in ultrasound in early adulthood could probably predict possible renal deterioration in later life. The occurrence of one small kidney was a common finding and seemed not to affect the prevalence of proteinuria or hypertension.

Patients with a history of infection and voiding dysfunction are at risk for recurrence after successful endoscopic treatment of vesico ureteral reflux and deserve long-term follow up

Aim of the Study:

Subureteral endoscopic injection of a bulking agent is an attractive alternative to open surgery or antibiotic prophylaxis for vesico ureteral reflux (VUR). Little information is available about long-term risk of recurrence after an initially successful treatment. Aim of this paper was to review short- and long-term success rate of endoscopic treatment in a single Center series after risk stratification of individual patients.

Materials and Methods:

The records of 126 patients who underwent Deflux injection for primary VUR were examined. Indications to treatment were an unvaried high grade VUR (IV-V) at 1 year from diagnosis and/or and recurrent urinary tract infection (UTI) on antibiotic prophylaxis even in the presence of mild grade VUR (III grade). Gender, age and mode of diagnosis, infections (UTI), voiding dysfunctions, VUR grade and side, renal function, number of treatments were correlated to outcome. Long-term evaluation was planned at a minimum of 1 year from the last negative post-injection cystogram (MCUG). A new MCUG and DMSA scan were also offered to those complaining new UTI episodes. Late recurrences were correlated to history and grade of reflux. Data were analyzed with Graph Pad Instat software; the Chi-square test was used for univariate comparisons, the Fisher's exact test for categorical variables.and multiple regression tests for factors influencing outcome.

Results:

M/F ratio was 62 to 64; median age at diagnosis was 28 months. VUR affected 198 renal units. Preinjection VUR grade was I in 1, II in 27, III in 107, IV in 59, and V in 4 units. Reduced DMSA uptake was evidenced in 51 units and scarring in 24. Median age at treatment was 34.5 months, for persistent high grade VUR (IV–V) in 55 patients and recurrent IVU in 92. Two hundred sixty seven injections were performed on 198 ureters. Complete resolution was documented by MCUG at 3-5 months in 68%, low grading < II in 20%, persistence or unsignificant reduction in 11%. Preoperative recurrent UTI, higher grade VUR, and bilaterality were correlated to a poorer surgical outcome. Among 80 successfully treated cases, 12 complained of persistent UTI. Recurrence of VUR was demonstrated in 31% of them. Deteriorated uptake or additional scarring in 25% was independent from VUR recurrence. Preoperative recurrent UTI and voiding dysfunction correlated significantly to late outcome.

Conclusions:

Preoperative recurrent IVU, together with high-grade reflux, seem to correlate to lower success rate of Deflux injection for primary VUR. Even after successful endoscopic treatment, long-term surveillance may be needed among these cases, mainly if voiding dysfunction is also recorded. Late recurring VUR must be actively excluded in case of new IVU episodes.

Long-term clinical consequences of urinary tract infections during childhood: a review

Kidney scarring related to urinary tract infection in childhood has been considered the cause of serious long-term clinical consequences. This assumption is now debated, as the advent of routine antenatal ultrasound in the 1980s has shown that a consistent part of the changes previously attributed to postinfectious scarring is mainly due to congenital malformations. With the aim of determining what is presently known on the long-term clinical consequences of urinary tract infections (UTIs) in childhood, we performed a review of the literature on the relation between UTIs and blood pressure, renal function, growth and pregnancy-related complications. By searching Medline/PubMed and Embase from 1980 to 2011, we identified 20 cohorts of children from 23 papers.

CONCLUSIONS

  Renal function: there are no clear data to establish long-term consequences following UTIs during childhood. Most data seem to show that the outcome of renal function can already be delineated at first presentation or in the initial years of follow-up; only 0.4% of children with normal renal function at start presented a decrease during follow-up. Hypertension: there is a low risk, associated with renal damage. Growth and pregnancy-related complications: the few available data seem to exclude a major influence of UTIs.

Clinical course of 822 children with prenatally detected nephrouropathies

BACKGROUND AND OBJECTIVES

With the advent of fetal screening ultrasonography, the detection of congenital anomalies of the kidney and urinary tract (CAKUT) in utero has permitted early management of these conditions. This study aims to describe the clinical course of a large cohort of patients with prenatally detected nephrouropathies.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

In this retrospective cohort study, 822 patients were prenatally diagnosed with CAKUT and systematically followed up at a tertiary Renal Unit for a median time of 43 months. Variables included in the analysis were sex, laterality, fetal ultrasonography (isolated versus associated hydronephrosis), and presence/absence of nephrouropathies. The events of interest were urinary tract infection, surgical interventions, hypertension, CKD, and death. Survival analyses were performed to evaluate time until occurrence of the events of interest.

RESULTS

Urinary tract infection occurred in 245 (29.8%) children, with higher risk in females (hazard ratio=1.30, 95% confidence interval=1.02-1.70, P=0.05); 22 patients (2.7%) had hypertension, and 49 (6%) patients developed CKD. The risk of CKD was greater in patients with associated hydronephrosis (hazard ratio=5.20, 95% confidence interval=2.90-9.30, P<0.001). Twelve patients (1.5%) died during follow-up. Death was significantly associated with being born during the first period of the study (hazard ratio=6.00, 95% confidence interval=1.60-22.50, P<0.001), associated hydronephrosis (hazard ratio=9.30, 95% confidence interval=2.90-29.30, P<0.001), and CKD (hazard ratio=170.00, 95% confidence interval=41.00-228.00, P<0.001).

CONCLUSIONS

In our series, the clinical course of prenatally detected CAKUT was heterogeneous, and those infants with associated hydronephrosis at baseline were identified as a high-risk subgroup.

Adherence to antibiotic prophylaxis in children with vesicoureteral reflux

Vesicoureteral reflux (VUR) affects approximately 1% of children and may predispose a child with a bladder infection to develop pyelonephritis and renal scarring. To prevent these potential sequelae, one accepted treatment option for VUR includes low-dose continuous antibiotic prophylaxis (CAP) to maintain urine sterility until the condition resolves. Despite the widespread use of CAP, little data exists regarding adherence to long-term antibiotic therapy. Not only will poor adherence to CAP potentially preclude the intended benefit, but also nonadherence with antibiotic regimens may carry untoward effects including unnecessary treatment changes for presumed antibiotic failure, emergence of resistant organisms, and compromised clinical trial outcomes. We present an overview of medication adherence in children with VUR, discuss possible consequences of nonadherence to antibiotic prophylaxis, and suggest ways to improve adherence. We raise awareness of issues related to nonadherence relevant to healthcare providers, investigators, and the community.

Primary, nonsyndromic vesicoureteric reflux and nephropathy in sibling pairs: a United Kingdom cohort for a DNA bank

BACKGROUND AND OBJECTIVES

Primary vesicoureteric reflux (VUR) can coexist with reflux nephropathy (RN) and impaired renal function. VUR appears to be an inherited condition and is reported in approximately one third of siblings of index cases. The objective was to establish a DNA collection and clinical database from U.K. families containing affected sibling pairs for future VUR genetics studies. The cohort's clinical characteristics have been described.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Most patients were identified from tertiary pediatric nephrology centers; each family had an index case with cystography-proven primary, nonsyndromic VUR. Affected siblings had radiologically proven VUR and/or radiographically proven RN.

RESULTS

One hundred eighty-nine index cases identified families with an additional 218 affected siblings. More than 90% were <20 years at the study's end. Blood was collected and leukocyte DNA extracted from all 407 patients and from 189 mothers and 183 fathers. Clinical presentation was established in 122; 92 had urinary tract infections and 16 had abnormal antenatal renal scans. RN was radiologically proven in 223 patients. Four patients had been transplanted; none were on dialysis. In 174 others aged >1 year, estimated GFR (eGFR) was calculated. Five had eGFR 15 to 59 and 48 had eGFR 60 to 89 ml/min per 1.73 m(2). Values were lower in bilateral RN patients than in those with either unilateral or absent RN.

CONCLUSIONS

The large DNA collection from families with VUR and associated RN constitutes a resource for researchers exploring the most likely complex, genetic components predisposing to VUR and RN.

Risk factors for recurrent urinary tract infection in infants with vesicoureteral reflux during prophylactic treatment: effect of delayed contrast passage on voiding cystourethrogram

OBJECTIVES

To investigate the risk factors for recurrent urinary tract infection (UTI) in infants with vesicoureteral reflux (VUR) because little is known regarding the risk factors for breakthrough infection.

METHODS

We compared children with infantile VUR with (20 boys, mean age 2.7 months) and without (20 boys and 4 girls, mean age 4.7 months) recurrent UTI. The factors compared included sex, timing of UTI episode, degree and bilaterality of the reflux, hydronephrosis, renal scar, associated congenital anomalies, voiding dysfunction, and delayed ureteral excretion of refluxed contrast on the voiding cystourethrogram.

RESULTS

Univariate Cox survival-time regression analysis showed that a younger mean age at the first UTI, bilateral reflux, and grade 4-5 VUR and hydronephrosis on the initial ultrasound scan significantly increased the risk of recurrent UTI (P<.05 each). On multivariate analysis, high-grade (P=.009) and bilateral (P=.016) VUR were independently associated with an increased risk of recurrent UTI. Of the infants with and without recurrent UTI, 80% and 0%, respectively, presented with high-grade VUR, as shown by delayed contrast passage on the voiding cystourethrogram. A urodynamic study of 11 infants with recurrent UTI showed decreased bladder capacity in 2 infants and a larger residual volume in 1 infant.

CONCLUSIONS

During the first year after birth, high-grade and bilateral VUR significantly increased the risk of recurrent UTI. Delayed contrast passage on the voiding cystourethrogram was significantly associated with an increased risk of recurrent UTI.

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.

Controversies in the management of vesicoureteral reflux: the rationale for the RIVUR study

The current management of vesicoureteral reflux (VUR) focuses on the prevention of urinary tract infections (UTI), with curative surgery being limited to those children that fail conservative measures. This is based on the assumption that UTIs are preventable with the use of prophylatic antibiotics, leading to reduction of renal scarring, and the possibility that VUR in children can resolve spontaneously.

METHODS

Review of the recent literature has demonstrated a growing concern that antibiotic prophylaxis may not lead to prevention of UTIs. Additionally, data indicate that renal scarring may not be preventable with antibiotic prophylaxis or even surgical correction of VUR. An overview of all of the current controversies is presented in this paper.

RESULTS

Does antibiotic prophylaxis lead to reduction in UTIs in children with VUR? To address this question, the National Institutes of Health have developed a randomized placebo-controlled study of children with VUR (the RIVUR Study), identified following the development of a UTI.

CONCLUSIONS

There are far reaching consequences of the results of the RIVUR Study. If antibiotic prophylaxis does not prevent UTI in children with VUR, or lead to reduction in renal scarring, does identification of VUR provide any benefits? Perhaps appropriate treatment of UTI may be all that is necessary for preserving renal function. Final answers will have to wait until the completion of this study.

Update on childhood urinary tract infection and vesicoureteral reflux

Urinary tract infection (UTI) is a leading cause of serious bacterial infection in young children. Vesicoureteral reflux (VUR), a common pediatric urologic disorder, is believed to predispose to UTI, and both are associated with renal scarring. The complex interaction of bacterial virulence factors and host defense mechanisms influence renal damage. However, some renal parenchymal abnormalities associated with VUR are noninfectious in origin. Long-term, renal parenchymal injury may be associated with hypertension, pregnancy complications, proteinuria, and renal insufficiency. Optimal management of VUR and UTI is controversial because of the paucity of appropriate randomized controlled trials; there is a need for well-designed studies. The recently launched Randomized Intervention for children with VesicoUreteral Reflux (RIVUR) study hopefully will provide insight into the role of antimicrobial prophylaxis of UTI in children with VUR.

Mutations in the ROBO2 and SLIT2 genes are rare causes of familial vesico-ureteral reflux

Familial clustering of vesico-ureteral reflux (VUR) suggests that genetic factors play an important role in the pathogenesis of this condition. The SLIT2 protein and its receptor, ROBO2, have key functions in the formation of the ureteric bud. Two recent studies have found that ROBO2 gene missense mutations are associated with VUR. In the study reported here, we investigated the genetic contribution of the SLIT2 and ROBO2 genes in non-syndromic familial VUR by mutation screening of 54 unrelated patients with primary VUR. Direct sequencing of all 26 exons and the exon-intron boundaries revealed six ROBO2 gene variants, two of which were new. Direct sequencing of all 37 exons and the exon-intron boundaries identified 20 SLIT2 gene variants, two of which were new. One variant, c.4253C > T, which was found in two families, leads to an amino acid substitution in a relatively well-conserved amino acid, p.Ala1418Val, which was predicted to cause an altered secondary structure but to have little impact on the three-dimensional structure. This missense variant did not segregate with VUR in these two families and was not found in 96 control subjects. We conclude that gene variants in ROBO2 and SLIT2 are rare causes of VUR in humans. Our results provide further evidence for the genetic heterogeneity of this disorder.

[Treatment of vesicouretheral reflux in pediatric patients]

BACKGROUND/AIM

Vesicouretheral reflux (VUR) is an inherited abnormality of the urinary tract caused by dysfunction of vesicouretheral junction frequently accompanied by recurrent urinary infection. The optimal treatment method of VUR is still controversial. The aim of the study was to analyze medical charts of children with VUR with special focus on the results of endoscopic treatment with Deflux.

METHODS

This retrospective study analyzed the medical charts of all children diagnosed with VUR at the Institute for Children and Youth Health Care of Vojvodina, in five years period. The analyzed data were: age, gender, grade, bilateral or unilateral presence of reflux, distribution to the sides of the body, urinary tract infections, associated anomalies and complications of VUR, treatment methods and the success rate of endoscopic correction with Deflux. Data processing was performed using the standard statistical methods.

RESULTS

The study included 167 patients (101 females and 66 males) with 231 refluxing ureters. The patients age at diagnosis was 1 month to 18 years (mean 4.6 years). Frequencies of different grades of VUR at initial investigation were: 17%, 27%, 22%, 21% and 13% for grades I to V, respectively. VUR was unilateral in 103 patients (left in 65 and right in 38), and bilateral in 64. Urinary tract infections were present in 78.4% of patients, reflux nephropathy in 38.3%, hypertension in 3.0%, chronic renal insufficiency in 4.8%, associated anomalies in 39.5% of patients. The treatment method was recorded in 154 cases. Medically were treated 80 patients, and surgically 74. Endoscopic injection of Deflux was carried out in 59 patients. From 79 ureters treated, five had grade I reflux, 11 grade II, 23 grade III, 27 grade IV, and 13 grade V. In 46 patients Deflux injection was carried out once. A second injection was required in eight, and third injection in five patients. Reflux was absent in 42 of the treated patients (71.2%) and 15 patients (25.4%) had a decreased grade of reflux after the treatment Overall success rate was 96.6%.

CONCLUSION

Endoscopic subureteral injection of Deflux is a minimally invasive method for VUR treatment in pediatric patients.

Management of childhood urinary tract infections: an economic modeling study

Childhood urinary tract infections (UTIs) can lead to renal scarring and ultimately to terminal renal failure, which has a high impact on quality of life, survival, and health-care costs. Variation in the treatment of UTIs between practices is high.

OBJECTIVE

To assess the cost-effectiveness of a maximum care model for UTIs in children, implying more testing and antibiotic treatment, compared with current practice in primary care in The Netherlands.

METHODS

We performed a probabilistic modeling study using Markov models. Figures used in the model were derived from a systematic review of the research literature. Multidimensional Monte Carlo simulation was used for the probabilistic analyses.

RESULTS

Maximum care gained 0.00102 (males) and 0.00219 (girls) QALYs (quality-adjusted life-years) and saved 42.70 euro (boys) and 77.81 euro (girls) in 30 years compared with current care, and was thus dominant. Net monetary benefit of maximum care ranged from 20 euro to 200 euro for a willingness to pay for a QALY ranging from 0 euro to 80,000 euro, respectively. Maximum care was also dominant over improved current care, although less dominant than to current care.

CONCLUSIONS

This study suggested that maximum care for childhood UTI was dominant in the long run to current care, meaning that it delivered more quality of life at lower costs. Nevertheless, making firm conclusions is not possible, given the limitations of the input data.

Predictors of renal scar in children with urinary infection and vesicoureteral reflux

We evaluated the predictors of renal scar in children with urinary tract infections (UTIs) having primary vesicoureteral reflux (VUR). Data of patients who were examined by dimercaptosuccinic acid (DMSA) scintigraphy between 1995 and 2005 were evaluated retrospectively. Gender, age, reflux grade, presence/development of scarring, breakthrough UTIs, and resolution of reflux, were recorded. The relation of gender, age and VUR grade to preformed scarring and the relation of gender, age, VUR grade, presence of preformed scarring, number of breakthrough UTIs and reflux resolution to new scarring were assessed. There were 138 patients [male/female (M/F) 53/85]. Multivariate analysis showed that male gender [odds ratio (OR) 2.5], age > or = 27 months in girls (OR 4.2) and grades IV-V reflux (OR 12.4) were independent indicators of renal scarring. On the other hand, only the presence of previous renal scarring was found to be an independent indicator for the development of new renal scar (OR 13.4). In conclusion, while the most predictive variables for the presence of renal scarring among children presenting with a UTI were male gender, age > or = 27 months in girls, and grades IV-V reflux, the best predictor of new scar formation was presence of previous renal scarring.

Antibiotic resistance patterns of community-acquired urinary tract infections in children with vesicoureteral reflux receiving prophylactic antibiotic therapy

OBJECTIVE

The goal was to examine bacterial antimicrobial resistance of recurrent urinary tract infections in children receiving antibiotic prophylaxis because of primary vesicoureteral reflux.

METHODS

We reviewed data retrospectively for children with documented vesicoureteral reflux in 2 hospitals during a 5-year follow-up period. The patients were receiving co-trimoxazole, cephalexin, or cefaclor prophylaxis or prophylaxis with a sequence of different antibiotics (alternative monotherapy). Demographic data, degree of vesicoureteral reflux, prophylactic antibiotics prescribed, and antibiotic sensitivity results of first urinary tract infections and breakthrough urinary tract infections were recorded.

RESULTS

Three hundred twenty-four patients underwent antibiotic prophylaxis (109 with co-trimoxazole, 100 with cephalexin, 44 with cefaclor, and 71 with alternative monotherapy) in one hospital and 96 children underwent co-trimoxazole prophylaxis in the other hospital. Breakthrough urinary tract infections occurred in patients from both hospitals (20.4% and 25%, respectively). Escherichia coli infection was significantly less common in children receiving antibiotic prophylaxis, compared with their initial episodes of urinary tract infection, at both hospitals. Children receiving cephalosporin prophylaxis were more likely to have an extended-spectrum beta-lactamase-producing organism for breakthrough urinary tract infections, compared with children with co-trimoxazole prophylaxis. Antimicrobial susceptibilities to almost all antibiotics decreased with cephalosporin prophylaxis when recurrent urinary tract infections developed. The extent of decreased susceptibilities was also severe for prophylaxis with a sequence of different antibiotics. However, antimicrobial susceptibilities decreased minimally in co-trimoxazole prophylaxis groups.

CONCLUSIONS

Children receiving cephalosporin prophylaxis are more likely to have extended-spectrum beta-lactamase-producing bacteria or multidrug-resistant uropathogens other than E coli for breakthrough urinary tract infections; therefore, these antibiotics are not appropriate for prophylactic use in patients with vesicoureteral reflux. Co-trimoxazole remains the preferred prophylactic agent for vesicoureteral reflux.

Clinical outcome of children with chronic kidney disease in a pre-dialysis interdisciplinary program

The purpose of this retrospective cohort study was to describe the outcome of 107 patients with chronic kidney disease (CKD) admitted to a pre-dialysis interdisciplinary management program from 1990 to 2006. The events of interest were progression to CKD stage 5 (renal survival), patient survival, hypertension, and somatic growth. Survival was studied by the Kaplan-Meier method. Patients were classified into four groups according to their primary renal disease: congenital nephro-uropathies; glomerular diseases; cystic disease, and miscellaneous. Median follow-up time was 94 months [Interquartile (IQ) range 38-145]. The probability of reaching CKD stage 5 was estimated to be 36% by 5 years after admission. As a whole, the mean estimated glomerular filtration rate (GFR) decrease per year was 5.8 ml/min per 1.73 m(2) body surface area [standard deviation (SD) 12.4]. The glomerular diseases group showed a median rate of GFR deterioration of 10 ml/min per 1.73 m(2) per year (IQ range -24 to -5.7), whereas the median rate of GFR deterioration for the groups with cystic diseases, congenital nephro-uropathies, and miscellanea were 2.5 ml/min (IQ range -10 to +0.34), 2.2 ml/min (IQ range -5.0 to -0.52), and 0.36 ml/min (IQ range -2.5 to +2.6), respectively (P < 0.001). The results of this study support the view that children and adolescents with glomerular diseases present a faster deterioration of renal function. Therefore, patients with glomerular diseases need to be referred early to a pediatric nephrology center so that suboptimal pre-dialysis care might possibly be avoided.

Vesicoureteral reflux, reflux nephropathy, and end-stage renal disease

Objective. To review the contribution of vesicoureteral reflux and reflux nephropathy to end-stage renal disease. Data Source. Published research articles and publicly available registries. Results. Vesicoureteral reflux (VUR) is commonly identified in pediatric patients and can be associated with reflux nephropathy (RN), chronic kidney disease (CKD), and rarely end-stage renal disease (ESRD). Patients with reduced GFR, bilateral disease, grade V VUR, proteinuria, and hypertension are more likely to progress to CKD and ESRD. Because progression to ESRD is rare in VUR and often requires many decades to develop, there are limited prospective, randomized, controlled trials available to direct therapy to prevent progression to ESRD. Conclusions. Identification of patients with increased risk of progression to CKD and ESRD should be the goal of clinical, biochemical, and radiological evaluation of patients with VUR. Treatment of patients with VUR should be directed at preventing new renal injury and preserving renal function.

Antibiotic prophylaxis for children with primary vesicoureteral reflux: where do we stand today?

The main goal of the management of vesicoureteral reflux (VUR) is prevention of recurrent urinary tract infections (UTIs), and thereby prevention of renal parenchymal damage possibly ensuing from these infections. Long-term antibiotic prophylaxis is common practice in the management of children with VUR, as recommended in 1997 in the guidelines of the American Urological Association. We performed a systematic review to ascertain whether antibiotics can be safely discontinued in children with VUR and whether prophylaxis is effective in the prevention of recurrent UTIs and renal damage in these patients. Several uncontrolled studies indicate that antibiotic prophylaxis can be discontinued in a subset of patients, that is, school-aged children with low-grade VUR, normal voiding patterns, kidneys without hydronephrosis or scars, and normal anatomy of the urogenital system. Furthermore, a few recent randomized controlled trials suggest that antibiotic prophylaxis offers no advantage over intermittent antibiotic therapy of UTIs in terms of prevention of recurrent UTIs or new renal damage.

The long-term outcome of antenatal hydronephrosis up to 15 millimetres justifies a noninvasive postnatal follow-up

AIM

To assess the incidence of urinary tract infections (UTIs) and surgery in infants with different grades of antenatal hydronephrosis (ANH) and to evaluate incidence, severity and course of underlying vesicoureteral reflux (VUR).

METHODS

Retrospective data of 125 infants with ANH were collected. The patients were divided into two groups according to the anterior-posterior pelvis diameter: group I, 5-14 mm and group II, > or =15 mm.

RESULTS

UTIs developed in 4 of 106 infants from group I and 5 of 19 infants from group II. Surgical interventions were performed on 1 of 106 patients of group I and 7 of 19 patients of group II. These differences were statistically significant (p-values 0.004 and <0.001, respectively). In group I, 6 of 106 patients had VUR; none of them required surgical intervention and only two developed a UTI (one of whom also had contralateral ureteropelvic junction obstruction). Five of 19 infants in group II had underlying VUR, four of them with associated anomalies, 1 infant required surgical correction and 4 developed UTIs.

CONCLUSION

Infants with ANH up to 15 mm have a low incidence of UTIs and surgery and a low incidence and benign course of underlying VUR. Therefore, noninvasive postnatal follow-up is justified and standard voiding cystourethrography should not be performed, but only in cases of ureteric dilatation.