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

AIM: Aim of the study was to provide a scoring system for predicting downgrading and resolution of infantile high-grade vesicoureteral reflux (VUR). METHODS: Eighty-nine infants (65 boys) with high-grade VUR (grade 4-5) diagnosed at median age 2.5 months and followed to 39 months had repeated investigations of VUR grade, renal damage/function and bladder function. Recurrent urinary tract infections (UTIs) were registered. Risk variables collected at 1 year were analysed as independent factors for spontaneous resolution to grades ≤2 and 0, using univariable/multivariable logistic regression. RESULTS: A scoring system was built with a total of 14 points from four independent risk factors (sex, breakthrough UTI, type of renal damage and subnormal glomerular filtration rate). Children with persistent VUR (grade 3-5) had higher scores compared with the group with spontaneous resolution (grade 0-2) (mean 7.9 vs. 4.5, P < .0001). A score of ≥8 points indicated a low probability of VUR resolution (≤14%). The model was considered excellent based on area under the ROC curve (0.82) and showed satisfactory internal validity. CONCLUSION: This model provides a practical tool in the management of infants born with high-grade reflux. High scores at one year of age indicate a high risk of persistent dilated reflux.

Changes in differential renal function after pyeloplasty in infants and children.

INTRODUCTION: Ureteropelvic junction obstruction (UPJO) is one of the most common causes of hydronephrosis in pediatric populations. Many need surgical intervention. The aim of surgery is preserving renal function and reducing symptoms such as urinary tract infections and pain. OBJECTIVES: The objectives were to evaluate differential renal function (DRF) in infants and children after surgery for UPJO and to identify factors predicting postoperative improvement. The difference in outcomes between patients with antenatal hydronephrosis and those diagnosed later was evaluated. STUDY DESIGN: A total of 85 children (63 boys and 22 girls) aged 0-16 years, treated for UPJO with dismembered pyeloplasty, were followed up as per a structured protocol including ultrasounds and renal scans (MAG-3) pre-operatively and three and 18 months postoperatively. Five children with bilateral or single kidney UPJO were excluded. Patient records were retrospectively reviewed, and the patients were grouped as per prenatal (group 1, n = 23) or postnatal (group 2, n = 57) diagnosis. Univariable and multivariable logistic regression analyses searching for factors predicting >5% postoperative improvement in DRF on the obstructed side were performed. Factors included in analyses were age at diagnosis and surgery, sex, type of presentation, cause of obstruction, estimated glomerular filtration rate, pre-operative DRF, anteroposterior diameter (APD), APD/renal parenchymal thickness, and grade of hydronephrosis as per the Onen alternative grading system (grade 1-4). RESULTS: Pre-operative DRF on the obstructed side was a mean of 42% (standard deviation, 12), with no difference between the groups. The median age at surgery was 0.9 (0.2-10) and 8.1 (0.6-16) years in groups 1 and 2, respectively (P < 0.001). The majority had unchanged DRF 18 months postoperatively, 19 (27%) patients improved by >5%, and one deteriorated. The proportion of patients with improved DRF was higher in group 1 (n = 10; 45%, P = 0.026). Anteroposterior diameter, APD/parenchymal thickness, pre-operative DRF, and antenatal diagnosis were predictors in the univariable analyses, and high APD (odds ratio [OR] = 1.1, P = 0.0023), antenatal diagnosis (OR = 0.23, P = 0.048), and low pre-operative DRF (OR = 0.90, P = 0.0045) built the best model of independent factors predicting improvement in DRF in multivariable analyses (Summary Figure). DISCUSSION: The limitation of the study is that it is retrospective, but it has the advantage of a uniform follow-up protocol, including patients from a five-year period, with few lost to follow-up. The results can be of interest in evaluating factors of importance for predicting recovery of function in obstructive uropathies in children. CONCLUSION: The majority of children had preserved or improved function after surgery for UPJO. Those with an antenatal diagnosis displayed a greater ability to catch up in DRF, and high APD, antenatal diagnosis, and low pre-operative DRF were independent predictive factors of an improvement in renal function after pyeloplasty.

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

BACKGROUND: Our objective was to analyze the evolution of kidney damage over time in small children with urinary tract infection (UTI) and factors associated with progression of renal damage. METHODS: From a cohort of 1003 children <2 years of age with first-time UTI, a retrospective analysis of 103 children was done. Children were selected because of renal damage at index 99mTc-dimercaptosuccinic acid (DMSA) scintigraphy at least 3 months after UTI, and a late DMSA scan was performed after at least 2 years. Damage was classified as progression when there was a decline in differential renal function (DRF) by ≥4%, as regression when there was complete or partial resolution of uptake defects. RESULTS: Of 103 children, 20 showed progression, 20 regression, and 63 remained unchanged. There were no differences between groups regarding gender or age. In the progression group, 16/20 (80%) children had vesicoureteral reflux (VUR) grade III-V and 13 (65%) had recurrent UTI. In multivariable regression analysis, both VUR grade III-V and recurrent UTI were associated with progression. In the regression group, 16/20 (80%) had no VUR or grade I-II, and two (10%) had recurrent UTI. CONCLUSIONS: Most small children with febrile UTI do not develop renal damage and if they do the majority remain unchanged or regress over time. However, up to one-fifth of children with renal damage diagnosed after UTI are at risk of renal deterioration. These children are characterized by the presence of VUR grades III-V and recurrent febrile UTI and may benefit from follow-up.

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

INTRODUCTION: High-grade vesicoureteral reflux (VUR) in children is associated with recurrent urinary tract infection (UTI) and renal damage. Breakthrough UTI despite continuous antibiotic prophylaxis (CAP) during the first years of life is a matter of concern and evokes early intervention. We investigated whether early endoscopic treatment (ET) of VUR grade 4-5 can reduce the risk of UTI recurrence and renal scarring. MATERIALS AND METHODS: This prospective, randomized, controlled, multicentre, 1-year follow-up trial comprised 77 infants, <8 months of age with VUR grade 4-5 (Table) randomized to CAP (n = 39) or ET (with prophylaxis until resolution) (n = 38). Voiding cystourethrogram, ultrasound, renal scintigraphy, and free voiding observation were performed at study entry and after 1 year. Parenchymal defects were seen in 67 (87%) children at entry, 39 (34 boys, 5 girls) of them characterized as generalized. At follow-up, renal deterioration (new scars or progress in old damaged area) and symptomatic UTIs were reported. RESULTS: There were 27 recurrent febrile UTIs in 6 (16%) children in the ET group and in 10 (26%) in the CAP group (p = 0.43), in eight (36%) girls and eight (15%) boys (p = 0.039). Successful VUR outcome (VUR 0-2) was seen in 22 (59%) in the ET and eight (21%) in the CAP group (p = 0.0014). Multiple recurrences were only seen in patients with persistent dilating reflux at follow-up (p = 0.019). Deterioration on scintigraphy was seen in eight children (9 kidneys) with no difference between treatment groups (p = 0.48) or sex (p = 0.17). Renal deterioration was associated with high bladder capacity (BC) and large residual volume (PVR) at 1 year (p = 0.0092 and p = 0.041). Six of the eight children with renal deterioration had a recurrent UTI (p = 0.0032). Seven of nine renal units with deterioration were seen in children with persistent VUR 3-5 at follow-up. Univariable logistic regression identified female sex and high PVR as positive predictors for recurrent UTI (p = 0.039 and 0.034) and high PVR tended to predict renal deterioration (p = 0.053). DISCUSSION: No differences between the treatment groups regarding recurrent UTI and renal deterioration could be found. Increased PVR and female sex were positive predictors for UTI recurrences. VUR grade at follow-up was correlated to UTI recurrence and renal deterioration. CONCLUSION: This study did not show any difference between ET and CAP in reducing the risk of UTI recurrence or renal deterioration. The rate of VUR resolution was higher in the ET group and VUR grade at follow-up correlated with both UTI recurrence and renal deterioration.

The Swedish infant high-grade reflux trial: Study presentation and vesicoureteral reflux outcome.

INTRODUCTION: High-grade vesicoureteral reflux (VUR) in infants is associated with congenital renal abnormalities, recurrent UTI, and bladder dysfunction. Endoscopic treatment (ET) is a well-established method in children with low to moderate reflux grades, but there is a lack of randomised controlled trials regarding the use of ET versus continuous antibiotic prophylaxis in infants with high-grade VUR. OBJECTIVE: This study aimed to determine whether high-grade VUR in infants can be treated with endoscopic injection and whether ET is superior to antibiotic prophylaxis in the treatment of VUR. MATERIALS AND METHODS: This prospective, randomised, controlled, multicentre, 1-year follow-up trial comprised 77 infants (55 boys, 22 girls) <8 months of age with VUR grade 4-5 (n = 30/n = 47). Of the infants, 52 (68%) had bilateral VUR. Thirty-nine were randomised to antibiotic prophylaxis and 38 to ET (with prophylaxis until resolution). Voiding cystourethrogram, ultrasound, renal scintigraphy, and free voiding observation were performed at study entry and after 1 year to evaluate VUR grade, and renal and bladder function. RESULTS: VUR grade ≤2 was seen in 22 (59%) infants in the endoscopy group and eight (21%) in the prophylaxis group at follow-up (p = 0.0014). The success rate in the endoscopy group was 100% in unilateral grade 4, falling to 31% in bilateral grade 5 (p = 0.0094). Correspondingly, the results in the prophylaxis group were 40% in grade 4 down to 0% in bilateral grade 5 (p = 0.037) (Table). Logistic regression analyses identified ET, VUR grade 4, unilaterality, and low residual urine at baseline as positive predictors of VUR down-grading to ≤2 (area under ROC curve 0.88). In four patients with reflux resolution after one injection, dilating reflux recurred at the 1-year follow-up. One patient had a UTI possibly related to ET. In our material four patients required re-implantation, of whom one was obstructive after injection. DISCUSSION: The opportunity to offer even small infants with high-grade VUR an alternative, minimally invasive treatment option is a great advance in paediatric urology. In this high-risk group, bilateral VUR grade 5 stands out with its poor bladder function and low chance of resolution. The recurrence rate of dilating VUR after successful ET is consistent with previous studies. The limitations are the relatively small number of patients and the short follow-up. CONCLUSION: High-grade VUR in infants can be treated with injection therapy and the resolution rate is higher than that of prophylaxis treatment. The complication rate is low and VUR grade 4, unilaterality, and low residual urine are favourable for the resolution and down-grading of VUR.

Urinary tract infection in infants: the significance of low bacterial count.

BACKGROUND: In national guidelines for urinary tract infection (UTI) in children, different cut-off levels for defining bacteriuria are used. In this study, the relationship between bacterial count in infant UTI and inflammatory parameters, frequency of vesicoureteral reflux (VUR), kidney damage, and recurrent UTI was analyzed. METHODS: We conducted a population-based retrospective study of 430 infants age <1 year with symptomatic UTI diagnosed by suprapubic aspiration. Clinical and laboratory parameters, findings on voiding cystourethrography and (99m)technetium dimercapto-succinic acid scintigraphy, and frequency of recurrence were related to bacterial count at the index UTI. RESULTS: Eighty-three (19%) infants had bacterial counts <100,000 colony-forming units (CFU)/ml and 347 (81%) had ≥100,000 CFU/ml. There was similar frequency of VUR (19% in both groups), kidney damage (17 and 23%, p = 0.33) and recurrent UTI (6 and 12%, p = 0.17) in the low and high bacterial group. Non-E. coli species were more prevalent (19 versus 6%, p = 0.0006) and mean C-reactive protein was lower (50 vs. 79 mg/l, p <0.0001) in the low bacteria group. CONCLUSIONS: UTI with low bacterial count is common and of importance since it may be associated with VUR and renal damage. Non-E. coli species and low inflammatory response were more prevalent in UTI with low bacterial count.

Renal function in adult women with urinary tract infection in childhood.

BACKGROUND: The risk of deterioration of renal function in patients with urinary tract infection (UTI)-associated renal damage over several decades is incompletely known but of importance in regard to follow-up. METHODS: A population-based cohort of women followed from their first UTI in childhood was studied at median age of 27 years and now at 41 years. Renal damage was evaluated by (99m)Tc-dimercaptosuccinic acid scan and glomerular filtration rate (GFR) by (51)Cr-edetic acid clearance. Extent of individual kidney damage was graded as class 1 to 3. RESULTS: Eighty-six women completed the investigation, 58 with renal damage, and 28 without. Of those with damage, one had chronic kidney disease (CKD) stage 3, 14 stage 2, and 43 stage 1. Women with bilateral damage had lower GFR than those with no or unilateral damage (p < 0.0001). Women with class 3 damage had numerically but not significantly lower GFR than the others with damage (p = 0.07). Between the two studies there was significant decrease of GFR in the group with bilateral damage (p = 0.01). CONCLUSIONS: Women with UTI-associated renal damage had remarkably well preserved renal function, but those with bilateral or severe individual kidney damage may be considered for regular monitoring of GFR and blood pressure.

Twenty-four-hour ambulatory blood pressure in adult women with urinary tract infection in childhood.

OBJECTIVE: To study 24-h ambulatory blood pressure (BP) and development of hypertension over four decades in women with childhood urinary tract infection (UTI) associated with renal damage. METHODS: A population-based group of 111 women was followed from their first UTI in childhood. The cohort was investigated at a median age of 27 years using standardized office BP measurement and was reinvestigated 15 years later with 24-h ambulatory BP monitoring (ABPM) and Tc-dimercaptosuccinic acid scan for evaluation of renal damage. RESULTS: Eighty-six women with median age 41 years completed the reinvestigation. Hypertension occurred in 26 women, four of 28 (14%) without and 22 of 58 (38%) with renal damage (P = 0.04). The hypertension was diagnosed before entry in seven and in the study by ABPM in another 19 women. In 78 women, of which 50 had renal damage, the ABPMs were correlated to renal damage. There was significant difference between the groups without and with renal damage when mean 24-h systolic, mean daytime systolic and mean night-time SBP were compared (P = 0.03, P = 0.04, P = 0.01, respectively). The results remained significant when the group with damage was divided into subgroups with increasing extent of damage: class 1, 2 and 3 (P = 0.01, P = 0.02, P = 0.008, respectively). CONCLUSION: Women with UTI-associated renal damage but well preserved function had significantly higher 24-h ambulatory BP and more often hypertension than comparable women without damage. This shows that women with UTI-associated renal damage are at increased risk of hypertension and should be considered for regular BP screening, preferably with 24-h ABPM.

Ultrasonography and renography to visualize upper urinary tract in children with meningomyelocele - a prospective study.

OBJECTIVE: Ultrasonography (US) is commonly used to visualize the upper urinary tract in children and adolescents with meningomyelocele (MMC). The aim of this investigation was to prospectively evaluate US in those with spinal angulation or obesity and compare it to the corresponding results obtained by mercaptoacetyltriglycine renography. PATIENTS AND METHODS: Twenty-five children and adolescents with MMC and pronounced angulation of the spine or obesity, were prospectively investigated with both US and renography during the period 2006 to 2008. RESULTS: In 13 (52%) patients the kidneys could not be fully evaluated; in 4 (16%) neither renal size nor pelvic dilation, in 12 (48%) renal length and in 5 (20%) dilation was not accessible. In 23 individuals where dilatation could be evaluated uni- or bilaterally, US was compared to OEE% (%outflow excretion efficiency) at renography. In 1 of these individuals there was normal OEE% while slight dilatation on US was noticed. In 2/15 individuals, split function at renography did not correlate with renal length on US. CONCLUSION: Severe spinal angulation and obesity in individuals with MMC reduced the possibility to evaluate the urinary tract by US. However, it seems that renography could be a reliable alternative to evaluate renal condition in those patients where US is insufficient.

Guidelines for standard and diuretic renogram in children.

Special consideration needs to be given to children who undergo dynamic renography. The Paediatric Committee of the European Association of Nuclear Medicine has updated the previous guidelines. Details are provided on how to manage the child, the equipment, and the acquisition and processing protocols. The pitfalls, difficulties and controversies that are encountered are also discussed, as well as the interpretation of the results.

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.

The Swedish reflux trial in children: I. Study design and study population characteristics.

PURPOSE: We compared the rates of febrile urinary tract infection, kidney damage and reflux resolution in children with vesicoureteral reflux treated in 3 ways, including antibiotic prophylaxis, endoscopic therapy and surveillance with antibiotics only for symptomatic urinary tract infection. MATERIALS AND METHODS: Children 1 to younger than 2 years with grade III-IV reflux were recruited into this prospective, open, randomized, controlled, multicenter study and followed for 2 years after randomization. The main study end points were recurrent febrile urinary tract infection, renal status on dimercapto-succinic acid scintigraphy and reflux status. Outcomes were analyzed by the intent to treat principle. RESULTS: During a 6-year period 128 girls and 75 boys entered the study. In 96% of cases reflux was detected after urinary tract infection. The randomization procedure was successful and resulted in 3 groups matched for relevant factors. Recruitment was slower than anticipated but after patients were entered adherence to the protocol was good. Of the children 93% were followed for the intended 2 years without a treatment arm change. All except 2 patients completed 2-year followup scintigraphy. CONCLUSIONS: Recruitment was difficult but a substantial number of children were entered and randomly assigned to 3 groups with similar basic characteristics. Good adherence to the protocol made it possible to address the central study questions.

The Swedish reflux trial in children: IV. Renal damage.

PURPOSE: We compared the development of new renal damage in small children with dilating vesicoureteral reflux randomly allocated to antibiotic prophylaxis, endoscopic treatment or surveillance as the control group. MATERIALS AND METHODS: Included in the study were 128 girls and 75 boys 1 to younger than 2 years with grade III-IV reflux. Voiding cystourethrography and dimercapto-succinic acid scintigraphy were done before randomization and after 2 years. Febrile urinary tract infections were recorded during followup. Data analysis was done by the intent to treat principle. RESULTS: New renal damage in a previously unscarred area was seen in 13 girls and 2 boys. Eight of the 13 girls were on surveillance, 5 received endoscopic therapy and none were on prophylaxis (p = 0.0155). New damage was more common in children with than without febrile recurrence (11 of 49 or 22% vs 4 of 152 or 3%, p <0.0001). CONCLUSIONS: In boys the rate of new renal damage was low. It was significantly higher in girls and most common in the control surveillance group. There was also a strong association between recurrent febrile UTIs and new renal damage in girls.

Value of ultrasound in evaluation of infants with first urinary tract infection.

PURPOSE: We evaluated the role of ultrasound in diagnosing and treating infants with a first urinary tract infection with a focus on important structural abnormalities. MATERIALS AND METHODS: In a setting of limited prenatal ultrasound screening this population based, prospective, 3-year study included 161 male and 129 female infants. Ultrasound and dimercapto-succinic acid scintigraphy were performed as initial investigations and voiding cystourethrography was conducted within 2 months. RESULTS: Ultrasound revealed dilatation in 15% of patients and increased kidney length in 28%. Sensitivity for detecting scintigraphic abnormality was 48%. Renal length was significantly correlated to inflammatory parameters, including scintigraphic abnormalities. Important structural abnormalities were detected in 40 cases, with 30 on ultrasound, while 10 of 27 cases of dilating reflux (mostly grade III) were missed. Outside the study there were 28 additional cases of structural abnormality, of which 15 were detected prenatally. CONCLUSIONS: Ultrasound detected most structural abnormalities except grade III reflux. Since it is noninvasive, ultrasound has a place in the evaluation of infants with urinary tract infection, especially in the absence of prenatal ultrasound during late pregnancy. Kidney length in infants with acute infection correlated with inflammatory parameters, and the clinical importance of this finding needs to be studied further.

Predictive factors for resolution of congenital high grade vesicoureteral reflux in infants: results of univariate and multivariate analyses.

PURPOSE: We studied variables with impact on cessation of congenital high grade vesicoureteral reflux in univariate analyses and provide a multivariate model for prediction of reflux resolution. MATERIALS AND METHODS: A total of 80 male and 35 female infants (median age 2.7 months) were included in this prospective observational study. Of the cases 71% were diagnosed after urinary tract infection and 26% after prenatal ultrasound. Reflux was bilateral in 70% of the patients and maximum grade was III in 16%, IV in 45% and V in 39%. The study protocol included repeat videocystometries, renal scintigrams, chromium edetic acid clearances and free voiding observations. Median followup was 36 months. RESULTS: Overall spontaneous reflux resolution, including cases downgraded to grade I to II, was 38%. Variables significantly negatively correlated to resolution were breakthrough febrile urinary tract infection, bladder dysfunction, higher grade of reflux at inclusion, renal abnormality, subnormal renal function, increased bladder capacity, residual urine and passive occurrence of reflux. Multivariate Cox proportional hazard model with stepwise selection identified 3 independent predictors--renal abnormality (hazard ratio 0.45, 95% CI 0.31-0.64, p <0.0001), bladder dysfunction (hazard ratio 0.43, 95% CI 0.29-0.64, p <0.0001) and breakthrough urinary tract infection (hazard ratio 0.38, 95% CI 0.18-0.78, p = 0.009). Performance of the model was evaluated by the receiver operating characteristic curve, with a calculated area under the curve of 83%. CONCLUSIONS: Overall resolution rate in congenital high grade vesicoureteral reflux is high during the first years of life. By multivariate analyses renal abnormality, bladder dysfunction and breakthrough febrile urinary tract infection were identified as strong independent negative predictive factors for reflux resolution.

Change of urodynamic patterns in infants with dilating vesicoureteral reflux: 3-year followup.

PURPOSE: Reports concerning bladder dysfunction patterns in infants with high grade vesicoureteral reflux during the first year of life vs older children with reflux are contradictory. To describe the development of bladder function characteristics in children with congenital dilating reflux, we evaluated such infants urodynamically and followed them regularly for a 3-year period. MATERIALS AND METHODS: A total of 89 males and 25 females with grade III to V dilating reflux were evaluated 3 times using videocystometry at mean ages of 6, 20 and 40 months. RESULTS: Characteristics of the urodynamic pattern at 6 months could not be differentiated from normal patterns for that age, including low and normal bladder capacity, high voiding pressure levels, dyscoordination at voiding (80%) and overactivity during filling (60%). However, at 20 months the overall pattern was different, including increased bladder capacity and residual volume, normal voiding pressure, persistent overactivity during filling and dyscoordination at voiding. Bladder dysfunction was seen in 48 children (42%) at 20 months, of whom 34 primarily had high bladder capacity with incomplete emptying (dilated bladder dysfunction) and 14 had overactive bladder. Predictors for development of dilated bladder dysfunction at followup were high residual urine at 6-month examination and recurrent urinary tract infections. Recurrent infections were significantly correlated to high residual urine at all investigations and to detrusor overactivity at the 20-month examination. CONCLUSIONS: Urodynamic patterns changed between the first and second year of life in patients with dilating reflux, from an immature pattern with high pressure levels to high capacity bladder with incomplete voiding. Therefore, bladder dysfunction, which was seen in 42% of patients, was only possible to diagnose after the first year of life and was mainly seen as high capacity bladder with incomplete voiding.

Ultrasonography as predictor of permanent renal damage in infants with urinary tract infection.

AIM: To evaluate the ability of ultrasound (US) in infants (<1 year) with acute urinary tract infection (UTI), to identify those with permanent renal damage (PRD) at scintigraphy 1 year later. METHODS: US, dimercaptosuccinic acid scintigraphy and voiding cystourethrography were performed in 191 infants. RESULTS: US was abnormal in 46 infants (24%). PRD was found in 46 infants (24%); 19 of these had abnormal US (sensitivity 41%). In 145 infants without PRD, 27 had abnormal US (specificity 81%). Dilating reflux or verified obstruction occurred in 21 (11%) infants, of whom 18 (86%) had PRD while 28 of 170 (16%) without such diagnoses had PRD. Of 16 infants with dilating reflux, 9 (sensitivity 56%) had abnormal US and 14 (88%) PRD. Dilatation at US was seen in 27 children; 7 of these had dilating reflux and 5 verified obstruction. CONCLUSION: US performed in association with acute UTI had limited ability to identify children with PRD at (99m)Tc-dimercaptosuccinic acid (DMSA) 1 year later, although abnormal renal size was a strong indicator of renal damage. The ability of US to identify children with dilating reflux was also limited. However, once detected at US, dilatation of the urinary tract was associated with dilating reflux or obstruction in half of the cases. Our study confirms that dilating reflux and obstruction are strong indicators of PRD but only half of those who developed PRD had such diagnoses.

Urinary proteins in children with urinary tract infection.

The aim of this study was to test our hypothesis that the urinary excretion of C-reactive protein (CRP), alpha 1-microglobulin (A1M), retinol-binding protein (RBP) and Clara cell protein (CC16) is increased in children with urinary tract infection (UTI) and relates to renal damage as measured by acute dimercaptosuccinic acid (DMSA) scintigraphy. Fifty-two children <2 years of age with UTI were enrolled in the study, 44 of whom were febrile. The control group consisted of 23 patients with non-UTI infection and elevated serum CRP (s-CRP) levels. Thirty-six patients had abnormal DMSA uptake, classified as mild, moderate or severe damage (DMSA class 1, 2, 3, respectively). There was a significant association between DMSA class and the excretion of urinary RBP (u-RBP) and u-CC16. There was also a significant difference in u-CRP levels between children with UTI and control children with non-UTI infections, although u-CRP excretion was not significantly correlated to DMSA class. In conclusion, the urinary excretion of the low-molecular-weight proteins RBP and CC16 showed a strong association with uptake defects on renal DMSA scans. The urinary level of CRP seems to distinguish between children with UTI and other febrile conditions. A combination of these biomarkers may be useful in the clinical assessment of children with UTI.

Longitudinal development of renal damage and renal function in infants with high grade vesicoureteral reflux.

PURPOSE: We sought to study renal abnormality and renal function through time in infants with high grade vesicoureteral reflux. MATERIALS AND METHODS: This prospective observational study included 115 infants (80 boys and 35 girls) younger than 1 year with grade III to V vesicoureteral reflux. The diagnosis was made after prenatal ultrasound in 26% of the patients and after urinary tract infection in 71%. Patients were followed by renal scintigraphy, 51chromium edetic acid clearance and video cystometry. Median followup was 62 months. RESULTS: Renal abnormality, which was found in 90% of the children at followup, was generalized in 71% and focal in 29%. The abnormality was bilateral in 28% of the affected patients. Total glomerular filtration rate was less than 80% of expected in 30% of the patients. Single kidney function was less than 40% of expected total glomerular filtration rate in 71% of the patients. Renal status (parenchymal abnormality and function) remained unchanged through time in 84 of 108 available cases (78%), improved in 5 (5%) and deteriorated in 19 (18%). Predictive factors for deterioration were recurrent febrile urinary tract infection, bilateral abnormality and reduced total glomerular filtration rate. Deteriorated renal status was more common in cases diagnosed prenatally than in those detected after urinary tract infection. CONCLUSIONS: Among these infants with high grade vesicoureteral reflux renal abnormality was frequent and was associated with subnormal filtration of one of the kidneys. Decreased total glomerular filtration rate was seen in about a third of the patients. Overall deterioration of renal status was seen in only a fifth of the patients. Infection control seems to be an important factor to minimize the risk.