Scintigraphic screening for renal damage in siblings of children with symptomatic primary vesico-ureteric reflux

The prevalence of familial vesicoureteric reflux in infants with normal antenatal scans

AIM

To determine the prevalence of familial vesicoureteric reflux (VUR) by studying the outcomes of screening in a contemporary cohort of newborns with normal antenatal kidney scans.

METHODS

A review of screening outcomes in newborns with a first degree relative with VUR, normal antenatal scans and no prior urine infections between 2014-2019 at three maternity units in the North East of England was conducted. Imaging consisted of micturating cystourethrogram (MCUG) in all and renal tract ultrasound scan (RUS) routinely in two units and by clinician preference in one unit.

RESULTS

At a median age of 59 days, 265 infants underwent MCUG. High-grade VUR (Grades 3-5) was detected in 13 (4.9%) and low-grade VUR (Grades 1-2) in 24 (9.1%). In the 152 infants who had a RUS, abnormalities were detected in 21 (13.8%). An abnormal postnatal RUS has a low positive predictive value (14.3%) for high-grade VUR, but a normal RUS has a high negative predictive value (95.4%).

CONCLUSION

Compared to historical cohorts from two decades ago, the yield from familial VUR screening is low and unjustifiable in the setting of normal antenatal anomaly scans.

[Vesicoureteral reflux : Watchful waiting, surgery or antibiotic prophylaxis?]

Primary vesicoureteral reflux (VUR) is a dynamic disease with several factors influencing its course. Therapeutic options range from watchful waiting to open surgery. Multiple risk factors for the development of pyelonephritis are identified, which then determine the decision for the appropriate treatment option. They include age, gender, history of pyelonephritis and renal scarring, bladder and bowel dysfunction (BBD), circumcision status and parental preference. The use of continuous antibiotic prophylaxis (CAP) is becoming increasingly controversial with antibiotic resistance being a major concern. Aggressive treatment of BBD and infant circumcision can greatly reduce the risk for pyelonephritis and should always be considered and discussed. This article is soley concerned with primary VUR.

Incidence of Urinary Tract Infection Among Siblings of Children With Vesicoureteral Reflux

BACKGROUND

Siblings of children with vesicoureteral reflux (VUR) are at elevated risk of VUR. Screening siblings may identify VUR before a clinical illness such as a urinary tract infection (UTI), but the benefit of screening has not been demonstrated. We sought to determine the incidence of UTI among siblings, and we hypothesized that the sibling UTI rate is similar between screened and unscreened siblings.

METHODS

We performed a retrospective cohort analysis using insurance claims data (January 1, 2000, to December 31, 2009). Within each family, we identified the index VUR patient and siblings; we included siblings who were enrolled in the insurance plan from birth for at least 1 year. We identified siblings who were screened for VUR and/or had UTI. We investigated the association of screening and UTI, controlling for patient characteristics and clustering within families.

RESULTS

Among 617 siblings (associated with 497 index patients), 317 (51%) were girls. Median insurance enrollment time was 53.0 months, with 424 enrolled ≥3 years. Among those with 1 or 3 years of enrollment, the proportions of siblings who experienced UTI was 8.4% (52 of 617) and 10.4% (44 of 424), respectively. Median age at initial UTI was 32.7 months. A total of 223 siblings (36.0%) underwent sibling screening. There was no significant difference in UTI between screened and unscreened siblings (odds ratio 1.57, 95% confidence interval 0.87-2.85; P = .14). In multivariate analysis, screening was not associated with sibling UTI incidence (odds ratio 1.33, 95% confidence interval 0.68-2.60; P = .40).

CONCLUSIONS

Although UTI is relatively common among siblings of VUR patients, there was no statistically significant difference in UTI incidence between screened and unscreened siblings.

[Primary vesicoureteral reflux]

The never ending discussion about the diagnostics and treatment of vesicoureteral reflux (VUR) now includes arguments for diagnostic nihilism as well as invasive diagnostics and therapy, which is reminiscent of the debate on prostate cancer in adulthood. The common goal of all currently competing diagnostic strategies and approaches is the prevention of renal scars by the most effective and least burdensome approach. There is a difference between acquired pyelonephritic scars with VUR (acquired reflux nephropathy) and congenital reflux nephropathy (primary dysplasia) which cannot be influenced by any therapy.The VUR can be verified by conventional radiological voiding cystourethrography (VCUG), by urosonography, radionuclide cystography or even by magnetic resonance imaging (MRI). The guidelines of the European Association of Urology/European Society for Paediatric Urology (EAU/ESPU) recommend radiological screening for VUR after the first febrile urinary tract infection. Significant risk factors in patients with VUR are recurrent urinary tract infections (UTI) and parenchymal scarring and the patients should undergo patient and risk-adapted therapy. Infants with dilating reflux have a higher risk of renal scarring than those without dilatation of the renal pelvis. Bladder dysfunction or dysfunctional elimination syndrome represents a well-known but previously neglected risk factor in combination with VUR and should be treated prior to any surgical intervention as far as is possible.Certainly not every patient with VUR needs therapy. The current treatment strategies take into account age and gender, the presence of dysplastic or pyelonephritic renal scars, the clinical symptoms, bladder dysfunction and frequency and severity of recurrent UTI as criteria for the therapy decision. The use of an antibacterial prophylaxis as well as the duration is controversially discussed. Endoscopic therapy can be a good alternative to antibacterial prophylaxis or a surveillance strategy in patients with low grade VUR. In patients with dilating VUR and given indications for surgery, endoscopic treatment can be offered. However, parents should be completely informed about the significantly lower success rate of endoscopic therapy compared to open surgical procedures. The open surgical techniques guarantee the highest success rates and should be used in patients with a dilating VUR and high risk of renal damage.

[Vesicoureteral reflux: diagnostics and therapy]

The current management of vesicoureteral reflux (VUR) remains controversial. Recent well thought-out randomized studies on VUR in children have led to a debate on diagnostic and therapeutic algorithms. Individual parameters, such as age, gender, clinical course, renal function and scars, dysfunctional elimination syndrome and last but not least the compliance of the parents have gained in importance. Regarding recent data this article gives a summary of diagnostic steps and therapeutic management of VUR.

Costs and consequences of universal sibling screening for vesicoureteral reflux: decision analysis

OBJECTIVE

Our objective was to evaluate screening for vesicoureteral reflux (VUR) among siblings of patients with VUR, in terms of cost, radiation exposure, and number of febrile urinary tract infections (fUTIs) averted.

METHODS

We constructed a Markov model to evaluate 2 competing management options, that is, universal screening (cystographic evaluation of all siblings without symptoms) and usual care (cystographic evaluation of siblings only after fUTIs). Published data were used to inform all model inputs. Costs were estimated by using a societal perspective.

RESULTS

Universal screening yielded 2980 fUTIs, whereas usual care yielded 6330. Therefore, universal screening for VUR in a cohort of 100,000 siblings 1 year of age without symptoms resulted in the prevention of 1 initial fUTI per 3360 siblings, at an excess cost of $55,600 per averted fUTI, in comparison with usual care. These estimates were heavily dependent on screening age and the effectiveness of antibiotic prophylaxis; prevention of a single fUTI would require screening of 166 siblings 5 years of age and 694 siblings 10 years of age. Similarly, if prophylaxis was ineffective in preventing fUTIs, then up to 10,000 siblings would need to be screened for prevention of a single fUTI.

CONCLUSIONS

Prevention of a single fUTI would require screening of 30 to 430 siblings 1 year of age without symptoms, at an estimated excess cost of $56,000 to $820,000 per averted fUTI. These estimates are heavily dependent on screening age and the effectiveness of antibiotic prophylaxis.

The Society for Fetal Urology consensus statement on the evaluation and management of antenatal hydronephrosis

The evaluation and management of fetuses/children with antenatal hydronephrosis (ANH) poses a significant dilemma for the practitioner. Which patients require evaluation, intervention or observation? Though the literature is quite extensive, it is plagued with bias and conflicting data, creating much confusion as to the optimal care of patients with ANH. In this article, we summarized the literature and proposed recommendations for the evaluation and management of ANH.

Prospective, randomized trial comparing short and long intravenous antibiotic treatment of acute pyelonephritis in children: dimercaptosuccinic acid scintigraphic evaluation at 9 months

OBJECTIVE

We report a prospective, randomized, multicenter trial that compared the effect of 3 vs 8 days of intravenous ceftriaxone treatment on the incidence of renal scarring at 6 to 9 months of follow-up in 383 children with a first episode of acute pyelonephritis.

METHODS

After initial treatment with intravenous netilmicin and ceftriaxone, patients were randomly assigned to either 5 days of oral antibiotics (short intravenous treatment) or 5 days of intravenous ceftriaxone (long intravenous treatment). Inclusion criteria were age 3 months to 16 years and first acute pyelonephritis episode, defined by fever of >38.5 degrees C, C-reactive protein level of >20 mg/L, and bacteriuria at >10(5)/mL. All patients underwent 99m technetium-dimercaptosuccinic acid scintigraphy 6 to 9 months after inclusion. A total of 548 children were included, 48 of whom were secondarily excluded and 117 of whom were lost to follow-up or had incomplete data; therefore, 383 children were eligible, 205 of them in the short intravenous treatment group and 178 in the long intravenous treatment group.

RESULTS

At inclusion, median age was 15 months, median duration of fever was 43 hours, and median C-reactive protein level was 122 mg/L. A total of 37% (143 of 383) of patients had a vesicoureteral reflux grades 1 to 3. Patient characteristics at inclusion were similar in both groups, except for a significantly higher proportion of girls in the short intravenous treatment group. The frequency of renal scars at scintigraphy was similar in both groups. Multivariate analysis demonstrated that renal scars were significantly associated with increased renal height at initial ultrasound and with the presence of grade 3 vesicoureteric reflux.

CONCLUSIONS

The incidence of renal scars was similar in patients who received 3 days compared 8 days of intravenous ceftriaxone. Increased renal height at initial ultrasound examination and grade 3 vesicoureteric reflux were significant risk factors for renal scars.

Lack of association of IL8 gene polymorphisms with familial vesico-ureteral reflux

Vesico-ureteral reflux (VUR) is the most common inherited disorder of the lower urinary tract. Children with VUR are at risk for ongoing renal damage with subsequent infections. IL8 is an important inflammatory mediator which can be produced by epithelial cells of the renal tract in response to a variety of inflammatory stimuli. High serum concentrations of IL-8 have been reported in patients with chronic renal failure. Elevated IL-8 levels have been reported in the urine of patients with VUR and renal parenchymal scarring (RPS). More recently it was reported that urine IL-8 levels remain elevated in infants with VUR even in the absence of a urinary tract infection (UTI). Increased IL-8 expression has been shown to be associated with polymorphism at position -251 (rs4073) of the IL-8 promoter. The aim of this study was to examine the association of IL-8 gene polymorphism with familial VUR in a cohort of 219 siblings from 109 families affected with VUR, the largest such cohort tested to date. RPS was assessed using dimercaptosuccinic acid scintigraphy. Genotyping was performed in 219 siblings with VUR (157 without RPS, 62 with RPS) and 292 controls for the position -251 of IL-8 gene by polymerase chain reaction with tetra primers and gel analysis. Genotype was compared using the chi square test. Statistical significance was taken as a value of P < 0.05. There were no significant differences in IL-8 -251 genotype frequency between VUR patients and controls. Similarly, gender, severity of VUR and renal parenchymal scarring had no effect on IL-8 -251 genotype frequency. Although IL-8 urinary levels have been reported to be elevated in VUR, our data indicate that IL-8 gene is not involved in the pathogenesis of familial VUR or reflux nephropathy.

[Evidence-based medicine and vesicoureteral reflux]

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

Screening for vesicoureteral reflux and renal scars in siblings of children with known reflux

The incidence of vesicoureteral reflux (VUR) in the general population is less than 1%, but it is high in families with reflux. The reported prevalence of VUR among siblings of index patients with reflux has ranged from 4.7% to 51%. Reflux carries an increased risk of pyelonephritis and long-term renal impairment. The purpose of this study was to identify the age-related incidence and severity of reflux, and the frequency of associated renal parenchymal damage in siblings of children with reflux in order to assess the use of screening at different ages. Between October 1994 and February 2003, 40 siblings of 34 index patients were screened with direct voiding cystography. 99( m ) technetium (Tc)-dimercaptosuccinic acid (DMSA) nuclear renal scans were performed in siblings with VUR to detect renal scarring. The cystograms were interpreted as showing the presence or absence of VUR and the DMSA scan as symmetrical or asymmetrical differential function, with or without renal scarring. Of 40 siblings, 17 had VUR, representing an incidence of 42.5%. The mean age at study entry of the 15 boys and 25 girls was 63 months (range 6 months to 12 years). The majority of siblings with abnormal DMSA scans were asymptomatic. Reflux was unilateral in 12 siblings and bilateral in 5. Of the 17 refluxing siblings (22 refluxing ureters), 7 (41.17%) had a history of symptomatic urinary tract infection (UTI). The frequency of VUR was nearly equal in siblings over 6 years and those younger than 6 years. Of the 17 siblings with VUR, 16 had DMSA scintigraphy. Of these, 5 were normal and 11 (68.75%) showed abnormalities (7 asymmetrical differential function and 4 parenchymal defect), which was bilateral in 7 and unilateral in 4. In conclusion, this study confirms a significant overall incidence of VUR and renal parenchymal damage in the siblings of patients with known reflux. The prevalence of reflux in older siblings is similar to that in younger siblings. Our review suggests that all siblings over 6 years should undergo a screening cystogram, even in the absence of urinary tract infection. DMSA scintigraphy of asymptomatic siblings appears to be beneficial in preventing renal injury.

Impact of early screening for reflux in siblings on the detection of renal damage

OBJECTIVE

To assess the impact of screening siblings after detecting significant vesico-ureteric reflux (VUR) and renal scarring, as such screening might identify patients with VUR before urinary tract infections develop, but might also detect clinically insignificant VUR.

PATIENTS AND METHODS

We used a previously reported screening protocol to assess the clinical characteristics of patients, including the incidence of renal scarring, and their siblings, and compared the results. In all, 123 children were screened and 44 (36%) had VUR on voiding cystography. The median (range) age at screening was 9 (1-90) months.

RESULTS

The grades of VUR detected were < III in 61% and > or = III in 39%; VUR was bilateral in 48%. In all, 37 siblings with VUR were assessed by ultrasonography; 70% were normal, including 12 (32%) children with VUR of grade > or = III. When used, renal scintigraphy was normal in 74% of siblings, vs 18% of index patients. However, when screened after 2 years old, siblings had twice the risk of already having renal damage on renal scintigraphy (P = 0.04).

CONCLUSION

Early screening (< or = 2 years) appears to be more protective for avoiding renal damage than screening older patients. Thus we propose early screening in asymptomatic siblings to detect VUR before it becomes clinically significant.

Familial vesicoureteral reflux

PURPOSE

Vesicoureteral reflux is known to occur in families. We summarized worldwide data on the incidence and nature of vesicoureteral reflux in siblings of children with vesicoureteral reflux.

MATERIALS AND METHODS

We searched MEDLINE using the words siblings vesicoureteral reflux, familial vesicoureteral reflux, offspring vesicoureteral reflux and vesicoureteral reflux screening. All articles that we identified that were published from 1972 to 2002 were analyzed for the incidence of renal damage in siblings of patients with vesicoureteral reflux.

RESULTS

Siblings of patients with vesicoureteral reflux have a much higher incidence of reflux than the normal population. There is a direct relationship of patient age to the incidence and severity of reflux. Most investigators advocate screening asymptomatic siblings of patients with vesicoureteral reflux.

CONCLUSIONS

The incidence of sibling reflux is significant. When vesicoureteral reflux is discovered in symptomatic siblings, it is usually high grade and associated with a high incidence of reflux nephropathy. Randomized controlled studies are needed to compare renal damage in patients with reflux detected through screening to renal damage in those diagnosed after urinary tract infection to establish how much renal damage may be prevented by screening in asymptomatic siblings.

Screening siblings for vesicoureteral reflux

PURPOSE

Publications on screening the siblings of patients with reflux were reviewed to determine the overall incidence and severity of reflux and renal scarring in siblings, and identify factors that predict siblings more likely to have reflux.

MATERIALS AND METHODS

A MEDLINE search for 1985 to the present was performed. Of 34 articles on familial reflux only 11, including 1 abstract, on sibling screening were used in this analysis.

RESULTS

The mean incidence of reflux in siblings in all studies was 32% (570 of 1,768). Of the siblings with reflux approximately two-thirds had grades I to II disease. Only 22 of 1,051 siblings (2%) had reflux greater than grade III. Reflux was unilateral in 162 of 307 cases (53%). Certain factors predicted the chance of sibling reflux. Sibling age varied inversely with the incidence of reflux. A twin relationship and absent dysfunctional voiding symptoms in the index patient may predict a higher chance of reflux in a sibling. The mean incidence of renal abnormality in siblings with reflux was 11%. The incidence of reflux and renal abnormality in the sibling population undergoing screening was 3%. In more than half of the siblings with an abnormal renal evaluation there was no history of urinary tract infection.

CONCLUSIONS

The studies reveal an incidence of reflux in siblings greater than in the general population. These data do not prove that screening and treating asymptomatic siblings decreases infectious renal scarring. Studies in a control group that consider sibling age are still needed to determine the benefit of screening asymptomatic siblings.