Ambulatory blood pressure 16-26 years after the first urinary tract infection in childhood

External Validation of the UTICalc with and Without Race for Pediatric Urinary Tract Infection

OBJECTIVE

To validate externally the UTICalc, a popular clinical decision support tool used to determine the risk of urinary tract infections (UTIs) in febrile children, and compare its performance with and without the inclusion of race and at differing risk thresholds.

METHODS

We performed a retrospective, singlecenter case-control study of febrile children (2-24 months) in an emergency department. Cases with culture-confirmed UTI were matched 1:1 to controls. We compared the performance of the original model which included race (version 1.0) to a revised model which did not consider race (version 3.0). We evaluated model performance at risk thresholds between 2% and 5%.

RESULTS

We included 185 cases and 197 controls (median age 8.4 months; IQR, 4.4-13.0 months; 60.5% girls). When using UTICalc version 1.0, the model area under the receiver operator characteristic curve (AUROC) was 73.4% (95% CI 68.4%-78.5%), which was similar to the version 3.0 model (73.8%; 95% CI 68.7%-78.8%). When using a 2% risk threshold, the version 3.0 model demonstrated a sensitivity of 96.7% and a specificity of 25.0%, with declines in sensitivity and gains in specificity at higher risk thresholds. Version 1.0 of the UTICalc had 12 false negatives, of whom 10 were Black (83%); whereas version 3.0 had 6 false negatives, of whom 2 were Black (33%).

CONCLUSIONS

Versions of the UTICalc with and without race had similar performance to each other with a slight decline from the original derivation sample. The removal of race did not adversely affect the accuracy of the UTICalc.

Urethral discharge as an early manifestation of urinary tract infection in children ≤24 months old

Background

Children with febrile urinary tract infections (UTIs) are prone to kidney scarring if they are not treated promptly; however, ambiguous symptoms before fever onset makes the early detection of UTIs difficult. Our study aimed to identify urethral discharge as an early manifestation in children with UTI.

Methods

This study enrolled 678 children younger than 24 months with paired urinalysis and culture performed between 2015 and 2021; 544 children were diagnosed with UTIs. Clinical symptoms, urinalysis, and paired urine culture results were compared.

Results

Urethral discharge was observed in 5.1% of children with UTI and yielded a specificity of 92.5% for diagnosing UTI. Children with urethral discharge had a less severe UTI course, furthermore, nine of them received antibiotics before fever occurred and seven of them were free of fever during UTI course. Urethral discharge was associated with alkalotic urine and Klebsiella pneumonia infection.

Conclusions

Urethral discharge is an early symptom in children with UTI; it may present before fever onset and help ensure prompt antibiotic intervention.

Corticosteroids to prevent renal scarring in children with pyelonephritis: a systematic review and meta-analysis

BACKGROUND

Acute pyelonephritis is a common infection in children that may cause renal scarring. The aim of this systematic review and meta-analysis was to analyse the use of corticosteroid treatment to prevent renal scarring.

METHODS

We searched the PubMED, SCOPUS, Cochrane CENTRAL and Web of Science databases in June 2022 for (corticosteroid* or dexamethasone or prednisolone* or prednisone* or hydrocortisone*) AND pyelonephritis. Randomised controlled trials focusing on children were included. The intervention was corticosteroid treatment with antibiotics compared to antibiotics with or without a placebo. The main outcome was the presence of renal scars on dimercaptosuccinic acid scanning at follow-up. The evidence quality was assessed using the GRADE methodology and risk of bias 2.0 tool. We calculated the risk ratio (RR), absolute risk difference (RD) with 95% confidence intervals (CI) and the number needed to treat (NNT). We applied a fixed effects model due to low heterogeneity.

RESULTS

We screened 872 abstracts and included five full texts. Renal scarring at follow-up was found in 31/220 (14.1%) patients in the corticosteroid groups and 76/278 (27.3%) in the control groups (RR 0.65, CI 0.44-0.96, RD - 13.2%, NNT 8). The evidence quality was moderate. Two studies reported adverse events with no differences between the groups. The risk of bias analysis showed some concerns in four studies.

CONCLUSION

We found moderate quality evidence that adjuvant corticosteroid treatment could prevent renal scarring. Adverse events were insufficiently reported, and more research on their effectiveness and harm is therefore needed before using corticosteroids in clinical settings.

Febrile Urinary Tract Infections in Children: The Role of High Mobility Group Box-1

BACKGROUND

Differentiating between febrile lower urinary tract infection (LUTI) and acute pyelonephritis (APN) is crucial for prompt clinical management. We investigated whether the high mobility group box-1 (HMGB1) could be a useful biomarker in differentiating between LUTI or APN.

METHODS

We enrolled seventy-four pediatric patients with suspected LUTI/APN, according to the positive or negative renal scintigraphy (DMSA) scan. If the first DMSA findings were abnormal, a second DMSA was performed after six months. Voiding cystourethrography ruled out vesicoureteral reflux (VUR).

RESULTS

Higher serum (s) HMGB1 levels characterized the APN group when compared to LUTI patients (13.3 (11.8-14.3) versus 5.9 (5.2-6.8) ng/mL, p: 0.02), whereas there were no differences according to urine (u) HMGB1 values. sHMGB1 correlated with C-reactive protein (CRP) levels (β = 0.47; p: 0.02). Receiver operating characteristic curves identified the best diagnostic profile for detecting APN. sHMGB1 area under the curve was different from CRP (p: 0.01) and white blood cells (p: 0.003). After multivariate analyses, VUR (HR:4.81) and sHMGB1 (HR 1.16; p: 0.006) were independently associated with the risk of renal scarring development.

CONCLUSIONS

sHMGB1 could represent a marker to differentiate APN from LUTI. Measurement of sHMGB1 could select children for early intervention or long-term follow-up.

Urinary Tract Infection in Children

Symptoms of urinary tract infection (UTI) in young children are nonspecific and urine sampling is challenging. A safe and rapid diagnosis of UTI can be achieved with new biomarkers and culture of clean-catch urine, reserving catheterization or suprapubic aspiration for severely ill infants. Most guidelines recommend ultrasound assessment and use of risk factors to direct further management of children at risk of kidney deterioration. The increasing knowledge of the innate immune system will add new predictors and treatment strategies to the management of UTI in children. Long-term outcome is good for the majority, but individuals with severe scarring can develop hypertension and decline in kidney function.

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.

Nomogram for diagnosing acute pyelonephritis in pediatric urinary tract infection

BACKGROUND

For risk stratification and individualized treatment for children with urinary tract infection (UTI), they must be assessed for the presence of acute pyelonephritis (APN). Our study aimed to combine variables that can predict APN and establish a nomogram for clinical use.

METHODS

In total, 111 children <5 years old hospitalized at Kaohsiung Veterans General Hospital for UTI were classified into APN and simple UTI groups based on a technetium-99 m dimercaptosuccinic acid scan. Their demographic, laboratory test, and renal and urinary bladder sonography (RUBS) data were compared.

RESULTS

Fever peak of >39 °C, serum procalcitonin (PCT) ≥ 0.52 pg/mL, C-reactive protein (CRP) ≥ 2.86 mg/dL, and abnormal RUBS findings were independent variables for predicting APN in children. The nomogram established using the aforementioned variables had an area under the receiver operating characteristic curve (AUC) of 0.89, which was higher than those of PCT and CRP alone (0.776 and 0.774, respectively).

CONCLUSION

The combination of four variables had the highest power in predicting APN in children with UTI. The established nomogram is practical for clinical use.

[Antimicrobial resistance patterns in pediatric febrile urinary tract infection and empirical antibacterial therapy. An epidemiological study in secondary and tertiary care centers in the north-east of France in 2019-2020]

BACKGROUND

Febrile urinary tract infection (UTI) is a common health issue in pediatrics that can lead to serious infectious and renal complications, it requires early diagnosis and a targeted use of antibiotics. The aim of our study was to describe local bacterial agents causing febrile UTIs and their resistance patterns and confront the results with currently used empirical antibacterial therapy in pediatrics emergency departments in Strasbourg and Saverne.

PATIENTS AND METHODS

We used billing codes (international classification of diseases) to identify all inpatients treated for febrile UTIs in two French pediatric emergency departments between January 2019 and December 2020. Microbial results of urine cultures were retrieved from the laboratory information system.

RESULTS

Among 214 microbial results from 208 patients, the distribution of uropathogens was 82% Escherichia coli, with extended-spectrum beta-lactamase in 2.8%, 7% Enterococcus faecalis, 5% Klebsiella, 2% Proteus mirabilis. E. coli was resistant respectively to amoxicillin, amoxicillin/clavulanic acid and cotrimoxazol in 43, 33 and 14% of samples. A third-generation cephalosporin administered intravenously was mainly used (98%) as empirical treatment. Less than 2% of patients were treated with oral cephalosporin from the start.

CONCLUSION

We present the spectrum of uropathogens and susceptibility test results in pediatric UTIs as well as the susceptibility pattern of E. coli, a local treatment protocol was designed based on our results in conformity with national guidelines.

Adjuvant corticosteroids for prevention of kidney scarring in children with acute pyelonephritis: a systematic review and meta-analysis

BACKGROUND

Acute pyelonephritis in children may result in permanent kidney scarring that is primarily caused by inflammation during acute infection. Antibiotic therapy alone is not enough to significantly reduce kidney scarring, and adjuvant corticosteroid therapy has shown a significant reduction in inflammatory cytokines in urine prompting its evaluation in randomised controlled trials. A few clinical trials showed a trend towards a reduction in renal scarring but did not have an adequate sample size to show a significant effect. Therefore, we planned to synthesise the available evidence on the role of corticosteroids as adjuvant therapy in reducing kidney scarring.

OBJECTIVE

To assess the efficacy and safety of adjuvant corticosteroid therapy for the prevention of kidney scarring in children with acute pyelonephritis.

DESIGN

Systematic review and meta-analysis.

SETTING

Community-acquired febrile urinary tract infections.

PATIENTS

Children (less than 18 years) with acute pyelonephritis.

INTERVENTION

Adjuvant corticosteroid therapy (along with antibiotic treatment).

MAIN OUTCOME MEASURES

Primary: efficacy in preventing kidney scarring; secondary: serious adverse events associated with corticosteroid therapy.

RESULTS

Three randomised trials (529 children) were included. Corticosteroids are effective in lowering the risk of kidney scarring as compared with placebo (risk ratio (RR): 0.57; 95% CI 0.36 to 0.90). No significant increase risk of bacteraemia (RR: 1.38; 95% CI 0.23 to 8.23) and hospitalisation (RR: 0.87; 95% CI 0.3 to 2.55) was observed in corticosteroid group.

CONCLUSION

Moderate quality evidence suggests that short duration 'adjuvant corticosteroid therapy' along with routine antibiotic therapy in acute febrile urinary tract infection significantly reduces the risk of kidney scarring without any significant adverse effects.

How Swedish guidelines on urinary tract infections in children compare to Canadian, American and European guidelines

Urinary tract infections (UTI) are common in children and the guidelines focus on preventing kidney damage. We compared the 2013 national Swedish guidelines on UTIs in children with the guidelines from America, Canada, UK, Spain, Italy and European urologists. This showed that urinalysis and urine cultures are endorsed by all the guidelines, but sampling techniques and bacteria levels differ. They all recommend initial oral treatment and renal ultrasound to detect major anomalies in infants. The Swedish guidelines are more liberal on antibiotic prophylaxis. CONCLUSION: Differences in diagnostic criteria, workup and accepted methods for urine sampling were noted and are discussed.

Contemporary Management of Urinary Tract Infection in Children

Urinary tract infection (UTI) is common in children, and girls are at a significantly higher risk, as compared to boys, except in early infancy. Most cases are caused by Escherichia coli Collection of an uncontaminated urine specimen is essential for accurate diagnosis. Oral antibiotic therapy for 7 to 10 days is adequate for uncomplicated cases that respond well to the treatment. A renal ultrasound examination is advised in all young children with first febrile UTI and in older children with recurrent UTI. Most children with first febrile UTI do not need a voiding cystourethrogram; it may be considered after the first UTI in children with abnormal renal and bladder ultrasound examination or a UTI caused by atypical pathogen, complex clinical course, or known renal scarring. Long-term antibiotic prophylaxis is used selectively in high-risk patients. Few patients diagnosed with vesicoureteral reflux after a UTI need surgical correction. The most consequential long-term complication of acute pyelonephritis is renal scarring, which may increase the risk of hypertension or chronic kidney disease later in life. Treatment of acute pyelonephritis with an appropriate antibiotic within 48 hours of fever onset and prevention of recurrent UTI lowers the risk of renal scarring. Pathogens causing UTI are increasingly becoming resistant to commonly used antibiotics, and their indiscriminate use in doubtful cases of UTI must be discouraged.

Corticosteroids to prevent kidney scarring in children with a febrile urinary tract infection: a randomized trial

BACKGROUND

To evaluate the efficacy of adjuvant systemic corticosteroids in reducing kidney scarring. A previous study suggested that use of adjuvant systemic corticosteroids reduces kidney scarring in children radiologically confirmed to have extensive pyelonephritis. Efficacy of corticosteroids for children with febrile urinary tract infection (UTI) has not been studied.

METHODS

Children aged 2 months to 6 years with their first febrile UTI were randomized to corticosteroids or placebo for 3 days (both arms received antimicrobial therapy); kidney scarring was assessed using ^99mTc-dimercaptosuccinic acid kidney scan 5-24 months after the initial UTI.

RESULTS

We randomized 546 children of which 385 had a UTI and 254 had outcome kidney scans (instead of the 320 planned). Rates of kidney scarring were 9.8% (12/123) and 16.8% (22/131) in the corticosteroid and placebo groups, respectively (p = 0.16), corresponding to an absolute risk reduction of 5.9% (95% confidence interval: - 2.2, 14.1).

CONCLUSION

While children randomized to adjuvant corticosteroids tended to develop fewer kidney scars than children who were randomized to receive placebo, a statistically significant difference was not achieved. However, the study was limited by not reaching its intended sample size.

CLINICAL TRIAL REGISTRATION

Clinicaltrials.gov , NCT01391793, Registered 7/12/2011 Graphical abstract.

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.

Predictive factors for bacteremia in febrile infants with urinary tract infection

This study aimed to investigate the predictive factors of concomitant bacteremia occurring in febrile infants who initially presented with pyuria and fever, and were subsequently diagnosed with culture-proven urinary tract infection (UTI). We conducted a retrospective cohort study for January 2010–October 2018 that included infants younger than six months with febrile UTI at a tertiary hospital. The study included 463 patients, of whom 34 had a concomitant bacteremic UTI. Compared to those in the non-bacteremic urinary tract infection (UTI) group, the bacteremic UTI group had a lower mean age; higher levels of C-reactive protein (CRP), delta neutrophil index (DNI, reflects the fraction of immature granulocytes) and blood urea nitrogen (BUN); lower levels of hemoglobin (Hb) and albumin; and a lower platelet count. Vesicoureteral reflux (VUR) was detected nearly twice as often in patients with bacteremic UTI compared to those with non-bacteremic UTI (59.3% vs. 30.6%; P = 0.003). Univariate logistic analyses showed that age ≤90 days; higher DNI, CRP, and creatinine levels; lower Hb and albumin levels; and the presence of VUR were predictors for bacteremic UTI. On multivariate logistic regression analysis, age ≤90 days, higher DNI and CRP levels, and the presence of VUR were independent predictors of bacteremic UTI. The area under the receiver operating characteristic curve of the multivariate model was 0.859 (95% CI, 0.779–0.939; P < 0.001). Age ≤90 days, higher DNI and CRP values may help predict bacteremia of febrile infants younger than 6 months with UTI. Vesicoureteral reflux imaging is also recommended in infants with bacteremic UTI to evaluate VUR.

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.

Antibiotic Prophylaxis Prescribing Patterns of Pediatric Urologists for Children with Vesicoureteral Reflux and other Congenital Anomalies of the Kidney and Urinary Tract

OBJECTIVE

To determine pediatric urologists' antibiotic prophylaxis prescribing practices for children with vesicoureteral reflux (VUR) and other congenital anomalies of the kidney and urinary tract (CAKUT).

METHODS

Web-based survey of pediatric urologists about their practice of antibiotic prophylaxis in children with CAKUT.

RESULTS

We had a response rate of 17.8% (n = 73). The majority of respondents always or often prescribe prophylactic antibiotics for grade IV or V VUR, while greater variability was seen for lower grades of VUR. 47.9% of respondents report that they often or always prescribe antibiotics for patients with grade 4 hydronephrosis, and most respondents report that they never or rarely prescribe antibiotics for grade 1 or 2 hydronephrosis. The majority of respondents never or rarely prescribe antibiotics for horseshoe or solitary kidney (88% and 86%, respectively), but frequently prescribed antibiotic for ureterocele. For ectopic ureter, almost half of respondents prescribe prophylactic antibiotics always or often, whereas only 18% prescribe antibiotics always or often for duplication anomalies. Only 11% reported prescribing antibiotics for prophylaxis always or often for children with myelomeningocele.

CONCLUSION

We report notable variability in antibiotic prescribing patterns for children with CAKUT. Given the lack of guidelines around the use of prophylaxis in the majority of these conditions, standardization of care may be warranted to decrease this variability.

Interventions for primary vesicoureteric reflux

BACKGROUND

Vesicoureteric reflux (VUR) results in urine passing retrograde up the ureter. Urinary tract infections (UTI) associated with VUR have been considered a cause of permanent renal parenchymal damage in children with VUR. Management has been directed at preventing UTI by antibiotic prophylaxis and/or surgical correction of VUR. This is an update of a review first published in 2004 and updated in 2007 and 2011.

OBJECTIVES

The aim of this review was to evaluate the available evidence for both benefits and harms of the currently available treatment options for primary VUR: operative, non-operative or no intervention.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Specialised Register to 3 May 2018 through contact with the Information Specialist using search terms relevant to this review. Studies contained in the Specialised Register are identified through search strategies specifically designed for CENTRAL, MEDLINE, and EMBASE; handsearching conference proceedings, and searching the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

RCTs in any language comparing any treatment of VUR and any combination of therapies.

DATA COLLECTION AND ANALYSIS

Two authors independently determined study eligibility, assessed quality and extracted data. Dichotomous outcomes were expressed as risk ratios (RR) with 95% confidence intervals (CI) and continuous data as mean differences (MD) with 95% CI. Data were pooled using the random effects model.

MAIN RESULTS

Thirty four studies involving 4001 children were included. Interventions included; long-term low-dose antibiotics, surgical reimplantation of ureters, endoscopic injection treatment, probiotics, cranberry products, circumcision, and oxybutynin. Interventions were used alone and in combinations. The quality of conduct and reporting of these studies was variable, with many studies omitting crucial methodological information used to assess the risk of bias. Only four of the 34 studies were considered at low risk of bias across all fields of study quality. The majority of studies had many areas of uncertainty in the risk of bias fields, reflecting missing detail rather than stated poor design.Low-dose antibiotic prophylaxis compared to no treatment/placebo may make little or no difference to the risk of repeat symptomatic UTI (9 studies, 1667 children: RR 0.77, 95% CI 0.54 to 1.09; low certainty evidence) and febrile UTI (RR 0.83, 95% CI 0.56 to 1.21; low certainty evidence) at one to two years. At one to three years, antibiotic prophylaxis made little or no difference to the risk of new or progressive renal damage on DMSA scan (8 studies, 1503 children: RR 0.73, 95% CI 0.33 to 1.61; low certainty evidence). Adverse events were reported in four studies with little or no difference between treatment groups (1056 children: RR 0.94, 95% CI 0.81 to 1.08; ), but antibiotics increased the likelihood of bacterial drug resistance threefold (187 UTIs: RR 2.97, 95% CI 1.54 to 5.74; moderate certainty evidence).Seven studies compared long-term antibiotic prophylaxis alone with surgical reimplantation of ureters plus antibiotics, but only two reported the outcome febrile UTI (429 children). Surgery plus antibiotic treatment may reduce the risk of repeat febrile UTI by 57% (RR 0.43, 95% CI 0.27 to 0.70; moderate certainty evidence). There was little or no difference in the risk of new kidney defects detected using intravenous pyelogram at 4 to 5 years (4 studies, 572 children, RR 1.09, 95% CI 0.79 to 1.49; moderate certainty evidence)Four studies compared endoscopic injection with antibiotics alone and three reported the outcome febrile UTI. This analysis showed little or no difference in the risk of febrile UTI with endoscopic injection compared to antibiotics (RR 0.74, 95% CI 0.31 to 1.78; low certainty evidence). Four studies involving 425 children compared two different materials for endoscopic injection under the ureters (polydimethylsiloxane (Macroplastique) versus dextranomer/hyaluronic acid polymer (Deflux), glutaraldehyde cross-linked (GAX) collagen (GAX) 35 versus GAX 65 and Deflux versus polyacrylate polyalcohol copolymer (VANTRIS)) but only one study (255 children, low certainty evidence) had the outcome of febrile UTI and it reported no difference between the materials. All four studies reported rates of resolution of VUR, and the two studies comparing Macroplastique with Deflux showed that Macroplastique was probably superior to dextranomer/hyaluronic acid polymer (3 months: RR 0.50, 95% CI 0.33 to 0.78; 12 months: RR 0.54 95% CI 0.35 to 0.83; low certainty evidence)Two studies compared probiotic treatment with antibiotics and showed little or no difference in risk of repeat symptomatic UTI (RR 0.82 95% CI 0.56 to 1.21; low certainty evidence)Single studies compared circumcision with antibiotics, cranberry products with no treatment, oxybutynin with placebo, two different surgical techniques and endoscopic injection with no treatment.

AUTHORS' CONCLUSIONS

Compared with no treatment, the use of long-term, low-dose antibiotics may make little or no difference to the number of repeat symptomatic and febrile UTIs in children with VUR (low certainty evidence). Considerable variation in the study designs and subsequent findings prevented drawing firm conclusions on efficacy of antibiotic treatment.The added benefit of surgical or endoscopic correction of VUR over antibiotic treatment alone remains unclear since few studies comparing the same treatment and with relevant clinical outcomes were available for analysis.

Renal scar formation and kidney function following antibiotic-treated murine pyelonephritis

We present a new preclinical model to study treatment, resolution and sequelae of severe ascending pyelonephritis. Urinary tract infection (UTI), primarily caused by uropathogenic Escherichia coli (UPEC), is a common disease in children. Severe pyelonephritis is the primary cause of acquired renal scarring in childhood, which may eventually lead to hypertension and chronic kidney disease in a small but important fraction of patients. Preclinical modeling of UTI utilizes almost exclusively females, which (in most mouse strains) exhibit inherent resistance to severe ascending kidney infection; consequently, no existing preclinical model has assessed the consequences of recovery from pyelonephritis following antibiotic treatment. We recently published a novel mini-surgical bladder inoculation technique, with which male C3H/HeN mice develop robust ascending pyelonephritis, highly prevalent renal abscesses and evidence of fibrosis. Here, we devised and optimized an antibiotic treatment strategy within this male model to more closely reflect the clinical course of pyelonephritis. A 5-day ceftriaxone regimen initiated at the onset of abscess development achieved resolution of bladder and kidney infection. A minority of treated mice displayed persistent histological abscess at the end of treatment, despite microbiological cure of pyelonephritis; a matching fraction of mice 1 month later exhibited renal scars featuring fibrosis and ongoing inflammatory infiltrates. Successful antibiotic treatment preserved renal function in almost all infected mice, as assessed by biochemical markers 1 and 5 months post-treatment; hydronephrosis was observed as a late effect of treated pyelonephritis. An occasional mouse developed chronic kidney disease, generally reflecting the incidence of this late sequela in humans. In total, this model offers a platform to study the molecular pathogenesis of pyelonephritis, response to antibiotic therapy and emergence of sequelae, including fibrosis and renal scarring. Future studies in this system may inform adjunctive therapies that may reduce the long-term complications of this very common bacterial infection.

Summary: A new model of antibiotic-treated severe pyelonephritis offers a novel platform to study the molecular pathogenesis of pyelonephritis, response to antibiotic therapy, and sequelae, including fibrosis and renal scarring.

Nuclear Medicine in Pediatric Nephro-Urology: An Overview

In the context of ante-natally diagnosed hydronephrosis, the vast majority of children with a dilated renal pelvis do not need any surgical treatment, as the dilatation resolves spontaneously with time. Slow drainage demonstrated at Tc-99m-mercaptoacetyltriglycine (MAG3) renography does not necessarily mean obstruction. Obstruction is defined as resistance to urinary outflow with urinary stasis at the level of the pelvic-ureteric junction (PUJ) which, if left untreated, will damage the kidney. Unfortunately this definition is retrospective and not clinically helpful. Therefore, the identification of the kidney at risk of losing function in an asymptomatic patient is a major research goal. In the context of renovascular hypertension a DMSA scan can be useful before and after revascularisation procedures (angioplasty or surgery) to assess for gain in kidney function. Renal calculi are increasingly frequent in children. Whilst the vast majority of patients with renal stones do not need functional imaging, DMSA scans with SPECT and a low dose limited CT can be very helpful in the case of complex renal calculi. Congenital renal anomalies such as duplex kidneys, horseshoe kidneys, crossed-fused kidneys and multi-cystic dysplastic kidneys greatly benefit from functional imaging to identify regional parenchymal function, thus directing further management. Positron emission tomography (PET) is being actively tested in genito-urinary malignancies. Encouraging initial reports suggest that F-18-fluorodeoxyglucose (FDG) PET is more sensitive than CT in the assessment of lymph nodal metastases in patients with genito-urinary sarcomas; an increased sensitivity in comparison to isotope bone scans for skeletal metastatic disease has also been reported. Further evaluation is necessary, especially with the promising advent of PET/MRI scanners. Nuclear Medicine in paediatric nephro-urology has stood the test of time and is opening up to new exciting developments.

Circumcision Is Unethical and Unlawful

The foreskin is a complex structure that protects and moisturizes the head of the penis, and, being the most densely innervated and sensitive portion of the penis, is essential to providing the complete sexual response. Circumcision-the removal of this structure-is non-therapeutic, painful, irreversible surgery that also risks serious physical injury, psychological sequelae, and death. Men rarely volunteer for it, and increasingly circumcised men are expressing their resentment about it.Circumcision is usually performed for religious, cultural and personal reasons. Early claims about its medical benefits have been proven false. The American Academy of Pediatrics and the Centers for Disease Prevention and Control have made many scientifically untenable claims promoting circumcision that run counter to the consensus of Western medical organizations.Circumcision violates the cardinal principles of medical ethics, to respect autonomy (self-determination), to do good, to do no harm, and to be just. Without a clear medical indication, circumcision must be deferred until the child can provide his own fully informed consent.In 2012, a German court held that circumcision constitutes criminal assault. Under existing United States law and international human rights declarations as well, circumcision already violates boys› absolute rights to equal protection, bodily integrity, autonomy, and freedom to choose their own religion. A physician has a legal duty to protect children from unnecessary interventions. Physicians who obtain parental permission through spurious claims or omissions, or rely on the American Academy of Pediatrics' position, also risk liability for misleading parents about circumcision.

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.

Outcome of post-infectious renal scarring

In this issue of Pediatric Nephrology, Gebäck et al. from Gothenburg, Sweden, show that after a mean follow-up after childhood urinary tract infection of 41 years, kidney function decreases from a mean of 93 ml/min/1.73m(2) to 81 ml/min/1.73m(2). This was found in women with severe bilateral renal scarring. They had experienced their UTI during childhood in the 1950s and 1960s and had been drawn from a population-based cohort of more than 1,000 children. A previous paper on this same group of women had shown a higher systolic blood pressure of 3 mmHg during the day and 5 mmHg during the night compared with a control group. This contrasted with a follow-up study published earlier by the same group on two different cohorts in which no impairment of kidney function or increase in hypertension could be found. The present follow-up time was 13 years longer than that of any previous studies. Data on the long-term outcome of children who have had one or several urine infections is very important, as the fear of long-term complications has been driving the extensive investigations to which these children have traditionally been subjected. Further population-based follow-up data can help us to outline modern guidance on imaging after 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.

Urinary Measurement of Neutrophil Gelatinase Associated Lipocalin and Kidney Injury Molecule-1 Helps Diagnose Acute Pyelonephritis in a Preclinical Model

Background. The study assessed whether measurement of urinary biomarkers of acute kidney injury could be helpful in diagnosing acute pyelonephritis and subsequent scarring. Method. Escherichia coli J96 (0.3 mL inoculum containing 1 × 10⁹/mL) was directly injected into the renal cortex of 3-week-old female Sprague Dawley rats (n = 20), with saline substituted in a control group (n = 10). Following the injection, urine was collected 2, 7, 14, 28, and 42 days after injection. Urinary neutrophil gelatinase associated lipocalin (NGAL), kidney injury molecule-1 (Kim-1), and interleukin-18 were quantitatively measured using enzyme-linked immunosorbent assay (ELISA). The levels of the biomarkers were adjusted for creatinine. Time course changes within a group or between the groups were compared. Correlation analysis was performed to understand the relationship between urinary levels and histological scarring. Results. Significantly elevated urinary NGAL was evident at two and seven days after injection, and Kim-1 was elevated at two days after injection. Receiver operating characteristic analyses confirmed the sensitivity of these markers at these times. No urinary marker at acute stage of APN was correlated with the amount of future scarring, negating their predictive value. Conclusion. Urinary NGAL and Kim-1 could be helpful in diagnosing febrile urinary tract infection in children.

Prevalence of urinary tract infection in acutely unwell children in general practice: a prospective study with systematic urine sampling

BACKGROUND

Urinary tract infection (UTI) in children may be associated with long-term complications that could be prevented by prompt treatment.

AIM

To determine the prevalence of UTI in acutely ill children ≤ 5 years presenting in general practice and to explore patterns of presenting symptoms and urine sampling strategies.

DESIGN AND SETTING

Prospective observational study with systematic urine sampling, in general practices in Wales, UK.

METHOD

In total, 1003 children were recruited from 13 general practices between March 2008 and July 2010. The prevalence of UTI was determined and multivariable analysis performed to determine the probability of UTI.

RESULT

Out of 597 (60.0%) children who provided urine samples within 2 days, the prevalence of UTI was 5.9% (95% confidence interval [CI] = 4.3% to 8.0%) overall, 7.3% in those < 3 years and 3.2% in 3-5 year olds. Neither a history of fever nor the absence of an alternative source of infection was associated with UTI (P = 0.64; P = 0.69, respectively). The probability of UTI in children aged ≥3 years without increased urinary frequency or dysuria was 2%. The probability of UTI was ≥5% in all other groups. Urine sampling based purely on GP suspicion would have missed 80% of UTIs, while a sampling strategy based on current guidelines would have missed 50%.

CONCLUSION

Approximately 6% of acutely unwell children presenting to UK general practice met the criteria for a laboratory diagnosis of UTI. This higher than previously recognised prior probability of UTI warrants raised awareness of the condition and suggests clinicians should lower their threshold for urine sampling in young children. The absence of fever or presence of an alternative source of infection, as emphasised in current guidelines, may not rule out UTI in young children with adequate certainty.

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

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

History of recurrent urinary tract infection is not predictive of abnormality on voiding cystourethrogram

PURPOSE

The American Academy of Pediatrics recently recommended against routine voiding cystourethrograms (VCUGs) in children 2 to 24 months with initial febrile UTI, raising concern for delayed diagnosis and increased risk of UTI-related renal damage from vesicoureteral reflux (VUR). We assessed factors potentially associated with higher likelihood of abnormal VCUG, including UTI recurrence, which could allow for more judicious test utilization.

METHODS

We retrospectively reviewed all initial VCUGs performed at Children's Hospital of Michigan between January and June, 2010. History of recurrent UTI was ascertained by evidence of two or more prior positive cultures or history of "recurrent UTI" on VCUG requisition. Outcomes assessed included rates of VUR or any urologic abnormality on VCUG.

RESULTS

Two hundred and sixty-two patients met inclusion criteria. VUR was detected in 21.3 %, urologic abnormality including VUR in 27.4 %. Degree of bladder distension, department of referring physician, study indication, positive documented urine culture, and history of recurrent UTI or UTI and other abnormality were all not associated with increased likelihood of VUR or any urologic abnormality on VCUG.

CONCLUSION

VUR and VCUG abnormality are no more likely when performed after recurrent UTI or for UTI plus other abnormality. This reasons against postponing VCUG until after UTI recurrence, as positive findings are no more likely in this setting.

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.

Interventions for primary vesicoureteric reflux

BACKGROUND

Vesicoureteric reflux (VUR) results in urine passing retrograde up the ureter. Urinary tract infections (UTI) associated with VUR have been considered a cause of permanent renal parenchymal damage in children with VUR. Management of these children has been directed at preventing UTI by antibiotic prophylaxis and/or surgical correction of VUR. The optimum strategy is not clear.

OBJECTIVES

To evaluate the benefits and harms of different treatment options for primary VUR.

SEARCH STRATEGY

In August 2010 we searched CENTRAL, MEDLINE and EMBASE and screened reference lists of papers and abstracts from conference proceedings.

SELECTION CRITERIA

RCTs in any language comparing any treatment of VUR including surgical or endoscopic correction, antibiotic prophylaxis, non-invasive non-pharmacological techniques and any combination of therapies.

DATA COLLECTION AND ANALYSIS

Two authors independently searched the literature, determined study eligibility, assessed quality, extracted and entered data. We expressed dichotomous outcomes as risk ratios (RR) and their 95% confidence intervals (CI) and continuous data as mean differences (MD) and their 95% CI's Data were pooled using the random effects model.

MAIN RESULTS

Twenty RCTs (2324 children) were included. Long-term low-dose antibiotic prophylaxis compared to no treatment/placebo did not significantly reduce repeat symptomatic UTI (846 children: RR 0.68, 95% CI 0.39 to 1.17) or febrile UTI (946 children: RR 0.77, 95% CI 0.47 to 1.24) at two years. There was considerable heterogeneity in the analyses and only one study was adequately blinded. At one to three years, antibiotic prophylaxis reduced the risk of new or progressive renal damage on DMSA scan (446 children: RR 0.35, 95% CI 0.15 to 0.80). Side effects were infrequent when reported, but antibiotics increased the likelihood of bacterial drug resistance threefold (132 UTIs: RR 2.94, 95% CI 1.39 to 6.25).When long-term antibiotic prophylaxis was compared with surgical or endoscopic correction of VUR plus antibiotics for one to 24 months (10 studies, 1141 children), the risk of symptomatic UTI was not significantly different at any time point. Combined surgical and antibiotic treatment caused a 57% reduction in febrile UTI by five years (2 studies, 449 children: RR 0.43, 95% CI 0.27 to 0.70) but did not decrease the risk of new or progressive renal damage at any time point. Postoperative obstruction was seen in 0% and 7% of children in two surgical studies and 0% in one endoscopic study.

AUTHORS' CONCLUSIONS

Compared with no treatment, use of long-term, low-dose antibiotics did not significantly reduce the number of repeat symptomatic and febrile UTIs in children with VUR. Considerable heterogeneity in the analyses and inclusion of only one adequately blinded study, made drawing firm conclusions challenging. Antibiotic prophylaxis significantly reduced the risk of developing new or progressive renal damage, but assuming an 8% baseline risk, 33 children would need long-term antibiotic prophylaxis to prevent one more child developing kidney damage over the course of two to three years.The added benefit of surgical or endoscopic correction of VUR over antibiotic treatment alone remains unclear. Eight children would require combined surgical and antibiotic treatment to prevent one additional child developing febrile UTI by five years, but it would not cause fewer children developing renal damage.

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.

Imaging strategy for infants with urinary tract infection: a new algorithm

PURPOSE

We analyzed clinical data for prediction of permanent renal damage in infants with first time urinary tract infection.

MATERIALS AND METHODS

This population based, prospective, 3-year study included 161 male and 129 female consecutive infants with first time urinary tract infection. Ultrasonography and dimercapto-succinic acid scintigraphy were performed as acute investigations and voiding cystourethrography within 2 months. Late scintigraphy was performed after 1 year in infants with abnormality on the first dimercapto-succinic acid scan or recurrent febrile urinary tract infections. End point was renal damage on the late scan.

RESULTS

A total of 270 patients had end point data available, of whom 70 had renal damage and 200 did not. Final kidney status was associated with C-reactive protein, serum creatinine, temperature, leukocyturia, non-Escherichia coli bacteria, anteroposterior diameter on ultrasound and recurrent febrile urinary tract infections. In stepwise multiple regression analysis C-reactive protein, creatinine, leukocyturia, anteroposterior diameter and non-E.coli bacteria were independent predictors of permanent renal damage. C-reactive protein 70 mg/l or greater combined with anteroposterior diameter 10 mm or greater had sensitivity of 87% and specificity of 59% for renal damage. An algorithm for imaging of infants with first time urinary tract infection based on these results would have eliminated 126 acute dimercapto-succinic acid scans compared to our study protocol, while missing 9 patients with permanent renal damage.

CONCLUSIONS

C-reactive protein can be used as a predictor of permanent renal damage in infants with urinary tract infection and together with anteroposterior diameter serves as a basis for an imaging algorithm.

Risk of renal scarring in children with a first urinary tract infection: a systematic review

BACKGROUND

To our knowledge, the risk of renal scarring in children with a urinary tract infection (UTI) has not been systematically studied.

OBJECTIVE

To review the prevalence of acute and chronic renal imaging abnormalities in children after an initial UTI.

METHODS

We searched Medline and Embase for English-, French-, and Spanish-language articles using the following terms: "Technetium (99m)Tc dimercaptosuccinic acid (DMSA)," "DMSA," "dimercaptosuccinic," "scintigra*," "pyelonephritis," and "urinary tract infection." We included articles if they reported data on the prevalence of abnormalities on acute-phase (≤15 days) or follow-up (>5 months) DMSA renal scans in children aged 0 to 18 years after an initial UTI. Two evaluators independently reviewed data from each article.

RESULTS

Of 1533 articles found by the search strategy, 325 full-text articles were reviewed; 33 studies met all inclusion criteria. Among children with an initial episode of UTI, 57% (95% confidence interval [CI]: 50-64) had changes consistent with acute pyelonephritis on the acute-phase DMSA renal scan and 15% (95% CI: 11-18) had evidence of renal scarring on the follow-up DMSA scan. Children with vesicoureteral reflux (VUR) were significantly more likely to develop pyelonephritis (relative risk [RR]: 1.5 [95% CI: 1.1-1.9]) and renal scarring (RR: 2.6 [95% CI: 1.7-3.9]) compared with children with no VUR. Children with VUR grades III or higher were more likely to develop scarring than children with lower grades of VUR (RR: 2.1 [95% CI: 1.4-3.2]).

CONCLUSIONS

The pooled prevalence values provided from this study provide a basis for an evidence-based approach to the management of children with this frequently occurring condition.

Does severity of renal scarring on DMSA scan predict abnormalities in creatinine clearance?

OBJECTIVES

To examine the relationship between severity of renal scarring and creatinine clearance. Existing studies on renal scarring and functional outcomes have focused on the presence or absence of scarring.

METHODS

Patients with a history of urinary tract infection leading to the diagnosis of vesicoureteral reflux were recruited. These subjects were admitted to a pediatric research center for an in-patient collection of 24-hour urine to be sent for creatinine and protein. DMSA scans performed at least 6 months after documented urinary tract infection were graded by 3 independent, blinded pediatric urologists for renal scarring according to the Randomized Intervention for Children with Vesicoureteral Reflux study criteria.

RESULTS

Twenty-nine subjects (14 girls, 15 boys) with a median age of 7 years were recruited. Scar grading was reliable between the observers with a Kappa score of 0.66-0.75. On DMSA scan, 10% were scar-free, 62% had unilateral scars, and 28% had bilateral scars. Mean creatinine clearance was 123 for those with unilateral disease and 100 for those with bilateral disease (P = .048). Median proteinuria (58 mg/dL) and serum creatinine (0.5 mg/dL) were similar between the 2 groups. Creatinine clearance did not differ according to average scar grade, taking both kidneys into account.

CONCLUSIONS

In children with vesicoureteral reflux, although those with bilateral scarring have a significantly lower creatinine clearance than those with unilateral scarring, the severity of scar grade alone does not predict overall creatinine clearance with short-term follow-up.

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.

Harmonic voiding urosonography with a second-generation contrast agent for the diagnosis of vesicoureteral reflux

BACKGROUND

Voiding urosonography with harmonic imaging (VUS HI) has been introduced as a sensitive and radiation-free imaging method for the diagnosis and follow-up of vesicoureteral reflux (VUR) in children.

OBJECTIVE

The purpose of this study was to evaluate the sensitivity of VUS HI using a second-generation US contrast agent compared to standard voiding cystourethrography (VCUG).

MATERIALS AND METHODS

A total of 228 children with 463 kidney-ureter units (KUUs) underwent two cycles of VUS HI and two cycles of VCUG at the same session. VUS HI was performed after intravesical administration of 1 ml of a second-generation US contrast agent (sulphur-hexafluoride gas microbubbles, SonoVue, Bracco, Italy). For statistical analysis we used McNemar's test, Student's t-test and k coefficient tests.

RESULTS

VUR was shown in 161/463 (34.7%) KUUs, 57 by both methods, 90 only by VUS, and 14 only by VCUG. Concordance in findings regarding the presence or absence of VUR was found in 359/463 (77.5%) KUUs (k=0.40). The difference in the detection rate of reflux between the two methods was significant (P<0.01). More importantly, reflux missed by VCUG was of higher grade (2 grade I, 65 grade II, 19 grade III, 4 grade IV) than that missed by VUS (8 grade I, 5 grade II, 1 grade III).

CONCLUSION

VUS HI and a second-generation contrast agent improved the identification of reflux in children. Our data reveal a higher sensitivity of the method compared to VCUG. Thus it can be used as an alternative radiation-free imaging method.

Randomised trial of oral versus sequential intravenous/oral cephalosporins in children with pyelonephritis

The hypothesis was tested that oral antibiotic treatment in children with acute pyelonephritis and scintigraphy-documented lesions is equally as efficacious as sequential intravenous/oral therapy with respect to the incidence of renal scarring. A randomised multi-centre trial was conducted in 365 children aged 6 months to 16 years with bacterial growth in cultures from urine collected by catheter. The children were assigned to receive either oral ceftibuten (9 mg/kg once daily) for 14 days or intravenous ceftriaxone (50 mg/kg once daily) for 3 days followed by oral ceftibuten for 11 days. Only patients with lesions detected on acute-phase dimercaptosuccinic acid (DMSA) scintigraphy underwent follow-up scintigraphy. Efficacy was evaluated by the rate of renal scarring after 6 months on follow-up scintigraphy. Of 219 children with lesions on acute-phase scintigraphy, 152 completed the study; 80 (72 females, median age 2.2 years) were given ceftibuten and 72 (62 females, median age 1.6 years) were given ceftriaxone/ceftibuten. Patients in the intravenous/oral group had significantly higher C-reactive protein (CRP) concentrations at baseline and larger lesion(s) on acute-phase scintigraphy. Follow-up scintigraphy showed renal scarring in 21/80 children treated with ceftibuten and 33/72 with ceftriaxone/ceftibuten (p = 0.01). However, after adjustment for the confounding variables (CRP and size of acute-phase lesion), no significant difference was observed for renal scarring between the two groups (p = 0.2). Renal scarring correlated with the extent of the acute-phase lesion (r = 0.60, p < 0.0001) and the grade of vesico-ureteric reflux (r = 0.31, p = 0.03), and was more frequent in refluxing renal units (p = 0.04). The majority of patients, i.e. 44 in the oral group and 47 in the intravenous/oral group, were managed as out-patients. Side effects were not observed. From this study, we can conclude that once-daily oral ceftibuten for 14 days yielded comparable results to sequential ceftriaxone/ceftibuten treatment in children aged 6 months to 16 years with DMSA-documented acute pyelonephritis and it allowed out-patient management in the majority of these children.

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.

Imaging in urinary tract infections: current strategies and new trends

The aim of imaging in a child with urinary tract infection (UTI) is to detect abnormalities that require appropriate treatment or findings that can be acted on to prevent development of complications (hypertension, chronic renal failure or pregnancy-related complications). Imaging protocols in pediatric urinary tract infections are evolving. From strategies based on extensive investigations in all children younger than 7 years of age, we are slowly moving to imaging strategies focused on children at risk of developing renal damage and possibly long-term complications. The article provides an overview on urinary tract infections, their complications and the use of imaging in their management. The different imaging strategies in children with UTIs (including the recommendation of excluding from imaging certain groups of patients) still needs full evaluation. It is interesting to note, however, a slow move from wide use of cystography in all children with UTI, which has been standard practice for many years but was probably not based on solid scientific evidence, toward a more focused use of cystograms in specific groups of children.

Imaging in childhood urinary tract infections: time to reduce investigations

The correct protocol for investigating urinary tract infections (UTI) is unknown but remains a hotly debated topic. The main objective in investigating children with UTI is to prevent the long-term complications of developing hypertension, chronic kidney disease (CKD) and/or pregnancy complications. However, the prognosis for childhood UTI remains good, with low long-term risks, from epidemiological studies, of developing these sequelae. Although childhood UTI is common, the occurrence of CKD and the likelihood that acute pyelonephritis will cause renal damage progressing to CKD are rare. We studied the current literature on investigations of childhood UTI and propose a protocol for carrying out selected investigations in high-risk children. By identifying this group of children with increased risk of having an abnormal urinary tract that warrant investigation, we recommend that targeting investigations to specific children (as opposed to protocol-based investigations of all children with UTI), will be clinically safe and effective and will avoid the unnecessary distress and cost of invasive investigations.

Interventions for primary vesicoureteric reflux

BACKGROUND

Vesicoureteric reflux (VUR) results in urine passing, in a retrograde manner, up the ureter. Urinary tract infections (UTIs) have been considered the main cause of permanent renal parenchymal damage in children with reflux. Management of these children has been directed at preventing infection by antibiotic prophylaxis and/or surgical correction of reflux. Controversy remains as to the optimum strategies.

OBJECTIVES

To evaluate the benefits and harms of different treatment options for primary VUR.

SEARCH STRATEGY

Randomised controlled trials (RCTs) were identified from the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, reference lists of articles and abstracts from conference proceedings. Date of last search: June 2006

SELECTION CRITERIA

Any treatment of VUR including surgery, antibiotic prophylaxis of any duration, non-invasive techniques and any combination of therapies.

DATA COLLECTION AND ANALYSIS

Two authors independently searched the literature, determined study eligibility, assessed quality, extracted and entered data. For dichotomous outcomes, results were expressed as relative risk (RR) and 95% confidence intervals (CI). Data were pooled using the random effects model.

MAIN RESULTS

Eleven studies (1148 children) were identified. Seven compared correction of VUR (by surgery or endoscope) plus antibiotics for 1-24 months with antibiotics alone, two compared antibiotics with no treatment and two compared different materials for endoscopic correction of VUR. Risk of UTI by 2, 5 and 10 years was not significantly different between surgical and medical groups (2 years RR 1.07, 95% CI 0.32 to 2.09; 5 years RR 0.99, 95% CI 0.79 to 1.26; 10 years RR 1.06, 95% CI 0.78 to 1.44). Combined treatment resulted in a 50% reduction in febrile UTI by 10 years (RR 0.54, 95% CI 0.55 to 0.92) but no concomitant reduction in risk of new or progressive renal damage by 10 years (RR 1.03, 95% CI 0.53 to 2.00). In two small studies no significant differences in risk for UTI (RR 0.75, 95% CI 0.15 to 3.84) or renal damage (RR 1.70, 95% CI 0.36 to 8.07) were found between antibiotic prophylaxis and no treatment.

AUTHORS' CONCLUSIONS

It is uncertain whether the treatment of children with VUR confers clinically important benefit. The additional benefit of surgery over antibiotics alone is small at best. Assuming a UTI rate of 20% for children with VUR on antibiotics for five years, nine reimplantations would be required to prevent one febrile UTI, with no reduction in the number of children developing any UTI or renal damage.

How have the past 5 years of research changed clinical practice in paediatric nephrology?

Clinical practice in paediatric nephrology is continuously evolving to mirror the research output of the 21st century. The management of antenatally diagnosed renal anomalies, urinary tract infections, nephrotic syndrome and hypertension is becoming more evidence based. Obesity and related hypertension is being targeted at primary and secondary care. The evolving field of molecular and cytogenetics is discovering genes that are facilitating clinicians and families with prenatal diagnoses and understanding of disease processes. The progression of chronic kidney disease in childhood to end-stage renal failure (ESRF) can be delayed using medical treatment to reduce proteinuria and treat hypertension. Pre-emptive living-related renal transplantation has become the treatment of choice for children with ESRF, thereby reducing the morbidity and mortality associated with peritoneal and haemodialysis. Although peritoneal dialysis, which is performed in the patient's home, is the preferred modality for children for whom there is no living or deceased donor for transplantation, home nocturnal haemodialysis is becoming a feasible option. Imaging modalities with the use of magnetic resonance and computerised tomography are continuously improving. As mortality for renal and vasculitic diseases improves, the gauntlet is now thrown down to reduce morbidity with secondary prevention of longer-term complications such as atherosclerosis and hyperlipidaemia. Clinical and drug trials in the fields of hypertension, nephrotic syndrome, systemic lupus erythematosus, vasculitis and transplantation are producing more effective treatments, thereby reducing the morbidity resulting from the disease processes and the side effects of drugs.

[Evaluation of renal lesions using 99mTc-DMSA in children with urinary tract infection and the relation with vesicoureteral reflux]

OBJECTIVE

Paediatric patients with urinary tract infection (UTI) have risk of developing renal scarrings. Although it is known that vesicoureteral reflux (VUR) predisposes to UTIs and it seems to have an important role in the development of renal lesions, some recent published studies question that relation. The aim of the study was to evaluate renal scarring by using renal scintigraphy 99mTc-DMSA and see the relation with or without the presence of VUR.

MATERIAL AND METHODS

We evaluated retrospectively a total of 230 patients (460 renal units), mean age: 11 months (range: 12d-5y), with UTI probed by urinoculture. All were studied with voiding cistourethrography (MCU) to evaluate the presence or absence of VUR. Patients were evaluated with 99mTc-DMSA scan 6 months after UTI to determine if UTI caused renal scarring.

RESULTS

Renal scans with 99mTc-DMSA 6 months post-infection were abnormal in 62 renal units, affecting 54 patients (23 %). From all patients studied, 110 were diagnosis of VUR being affected 161 renal units, 43 of them (27 %) presented renal scarrings. From the remaining 120 patients without VUR that is 240 renal units, 19 of them (8 %) presented parenchymatous damage.

CONCLUSION

Renal scarring resulting from UTI are in some cases related to VUR, but sometimes are caused by the infection itself. Not all patients with VUR develop renal lesions, and neither the presence of VUR always predispose children to renal lesions. MCU and direct isotopic cystography are useful for diagnosis of VUR but we shouldn't avoid 99mTc-DMSA scan in the management of children with UTI.