Acute pyelonephritis and renal scarring in Kuwaiti children: a follow-up study using 99mTc DMSA renal scintigraphy

Renal scarring in children with febrile urinary tract infection

OBJECTIVE

The authors aim to evaluate characteristics of children with fUTI and results of renal bladder ultrasonography (RBUS) and late dimercaptosuccinicacid (DMSA) scan.

METHODS

This study is designed as retrospective analysis of RBUS and DMSA reports of children with fUTI. Age, gender, number of fUTI, presence of constipation and vesicouretheral reflux (VUR) were recorded.

RESULTS

The study included 160 children with fUTI with a median age of 7 years (6 months 18 years old). The majority of children in this study were girls (86.3 %), older than 60 months (73.1 %) and had one episode of fUTI. The recurrence rates of UTI were similar in both girls and boys. The total rate of constipation was 21.9 %. The rate of renal scarring on DMSA was 16.9 %. The rates of renal scarring were similar at three age groups and both genders. The rate of renal scarring was higher in children with recurrent UTI compared to those with one episode of fUTI (26.4 % and 12.5 %, respectively; p = 0.04). The rate of constipation in children with renal scarring and normal DMSA was similar (p = 0.07). The rate of trabeculation and thick bladder wall was higher in children with renal scarring at DMSA than children with no renal scarring (p = 0.03).

CONCLUSION

The present study demonstrated that 16.9 % of children with fUTI had renal scarring. The rates of renal scarring were similar in both gender and age groups. Children with recurrent UTI and abnormal bladder results at RBUS had higher rates of renal scarring.

Patterns of damage observed on dimercaptosuccinic acid kidney scans and future risk of urinary tract infections or reduced kidney function

BACKGROUND

99mTc-Dimercaptosuccinic acid (DMSA) scan is highly accurate for assessing functional imaging of the kidney parenchyma. Kidney damage observed on DMSA scan is associated with future development of chronic kidney disease. This study aims to differentiate between different patterns of damage observed on DMSA scan and determine their predictive clinical value.

METHODS

We reviewed first-in-life DMSA scans performed ≥ 4 months post febrile urinary tract infection (UTI) or for suspected congenital kidney abnormalities, in a single referral center, from November 2007 to February 2011. DMSA uptake patterns were classified as normal; peripheral focal defects; diffuse inhomogeneity in tracer distribution within kidney parenchyma; and the combination of both patterns. Subsequent UTIs and estimated glomerular filtration rate (eGFR) were recorded at last follow-up.

RESULTS

One hundred five patients met inclusion criteria, and 57 (54%) were females. Median (IQR) age at scan was 2 (1.3, 5.1) years. Fourteen patients (13.3%) had focal defects, 29 (27.6%) had diffuse inhomogeneity and 9 (8.6%) had diffuse inhomogeneity with focal defects. After a mean follow-up period of 9.6 ± 3.3 years (available for 99 children), 29 (29%) patients experienced recurrent UTIs [median (IQR) episodes: 2 (1, 5)]. UTI tendency differed between groups (focal defects: 71.4%; diffuse inhomogeneity with focal defect: 44.4%; diffuse inhomogeneity only: 22.2%; normal scan: 18.3% p < 0.001). On multivariate analysis only the presence of focal defects predicted recurrent UTIs [OR (95%CI): 3.89 (1.2, 12.6), p = 0.024]. The percentage of patients with an eGFR < 75 ml/min/1.73 m2, was highest in patients with diffuse inhomogeneity with focal defects compared to patients with normal scans, focal defects only or diffuse inhomogeneity only (22% vs. 2%, 0% and 3.7% respectively, p = 0.032).

CONCLUSIONS

Focal defects on DMSA scan, likely representing post pyelonephritis scars, are a strong predictor of recurrent UTIs. Patients with diffuse inhomogeneity with focal defects on scan have the highest risk of reduced eGFR during follow-up.

Complete Remission of Renal Scarring in Follow-Up DMSA Renal Scintigraphy After Urinary Tract Infection

Our study aimed to investigate the association between the characteristics of patients/images and complete remission of renal scarring shown in the first chronic phase Technetium-99m dimercaptosuccinic acid (DMSA) renal scintigraphy images in children with urinary tract infection (UTI). Fifty children, who underwent the chronic phase of DMSA scintigraphy more than twice following UTI diagnosis and had renal scarring in the first chronic phase DMSA renal scintigraphy, were enrolled. They were classified into 2 groups: with and without complete remission of renal scarring on the second chronic phase DMSA renal scintigraphy. Renal scarring was classified into 3 grades based on severity per the image findings. Seven cases had complete remission from renal scarring. There were significant differences in age and severity. Renal scarring might be completely reversed in young children without severe findings on DMSA renal scintigraphy. Additional chronic phase examination may aid in follow-up completion and patients' peace of mind.

Risk factors for new renal scarring in children with vesicoureteral reflux receiving continuous antibiotic prophylaxis

To investigate the risk factors for new renal scarring (NRS) in children with vesicoureteral reflux (VUR) receiving continuous antibiotic prophylaxis (CAP). This was a single-center cohort study. The clinical data of 140 children with grade I-V VUR receiving CAP were analyzed. In this study, exposure variables were sex, younger age at the initial diagnosis of UTI ≤ 12 months, the occurrence of breakthrough urinary tract infection (BT-UTI), high-grade VUR, bilateral VUR, etiology, presence of renal scarring at the initial diagnosis and ultrasound abnormalities. The outcome was NRS. A total of 140 children were included in the risk factor analysis of NRS, 73 of whom experienced NRS, an incidence rate of 52.14%. Multivariate Cox regression suggested that the presence of renal function impairment after the initial diagnosis of UTI (OR 3.411, 95% CI 1.5751-6.646) and the occurrence of BT-UTI while receiving CAP (OR 1.995, 95% CI 1.089-2.958) were independent risk factors for NRS. Multivariate Cox regression showed that high-grade VUR had no significant effects on NRS (OR 0.940, 95% CI 0.462-1.912, P = 0.864). No significant difference was identified in multivariate Cox regression analysis in the IV-V group (vs I-III group) (OR 0.960, 95% CI 0.565-1.633, P = 0.960). Renal function impairment after the initial diagnosis of UTI and the occurrence of BT-UTI while receiving CAP were independent risk factors for NRS. Neither univariate analysis nor multivariate analysis found a correlation between VUR grade and NRS.

Incidence of renal scarring on technetium-99 m dimercaptosuccinic acid renal scintigraphy after acute pyelonephritis, acute focal bacterial nephritis, and renal abscess

OBJECTIVE

To evaluate the association between the incidence of renal scarring on technetium-99 m dimercaptosuccinic acid (DMSA) renal scintigraphy and the severity of renal parenchymal infections, such as acute pyelonephritis (APN), acute focal bacterial nephritis (AFBN), and renal abscess, based on computed tomography (CT) diagnosis.

METHODS

Sixty-one children with renal parenchymal infections were included and classified into two groups: those with (renal scarring group) and without renal scarring (non-renal scarring group) on chronic-phase DMSA renal scintigraphy. The severity of renal parenchymal infection was classified into three grades using CT: APN, AFBN, and renal abscess as grades 1, 2, and 3, respectively. The severity of renal parenchymal infection, vesicoureteral reflux (VUR) grade, and intrarenal reflux occurrence during voiding cystourethrography (VCUG) were evaluated between the renal and non-renal scarring groups. Fisher's exact test and Mann-Whitney U test were used for statistical analysis.

RESULTS

Renal scars were detected in 28 (45.9%) of the 61 patients. We found that 2/9 (22.2%), 18/41 (43.9%), and 8/11 (72.7%) patients with APN (grade 1), AFBN (grade 2), and renal abscess (grade 3) had renal scarring, respectively. There was a significant difference in the grade of severity of renal parenchymal infection between the renal (median = 2 [interquartile range, 2-3]) and non-renal (median = 2 [interquartile range, 2-2]) scarring groups (p = 0.023). There was a significant difference in the grade of VUR between the renal (median = 3 [interquartile range, 0-4]) and non-renal (median = 0 [interquartile range, 0-2]) scarring groups (p = 0.004). No significant difference in intrarenal reflux occurrence was observed between the renal (present/absent: 3/25) and non-renal (present/absent: 0/29) scarring groups (p = 0.112).

CONCLUSION

Our results showed that pediatric patients with renal scarring on chronic-phase DMSA renal scintigraphy tended to have a more severe renal infection.

Use of Temporary Double-J Stent Placement for Children With Congenital Hydronephrosis: A Long-Term Single-Center Cohort Study

OBJECTIVE

To evaluate the utilization of double-J stents in children with congenital hydronephrosis in order to avoid or postpone more invasive surgical intervention. Numerous studies have demonstrated that congenital hydronephrosis caused by ureteropelvic junction obstruction (UPJO) or primary obstructive megaureter (POM) may require a surgical correction in up to 20% of cases.

METHODS

All infants with severe hydronephrosis and/or an obstructive pattern on renal scintigraphy that received double-J stent placement between 2010 to 2015 in our center were analyzed. Children were followed regularly with ultrasound and received antibiotic metaphylaxis. Urinary tract infection (UTI) and double-J dislocation were defined as complications. Treatment success was defined as avoidance of surgery and reduction of hydronephrosis to grade 1 or 0 during the observation period.

RESULTS

29 children were included, in these, 34 (23 UPJO, 7 POM, 4 UPJO and POM) treatment attempts were performed. Stent implantation failed in six cases, resulting in 28 double-J stent treatments, of which 19 (69%) were successful within the follow-up period of 20 to 104 months. The most common complications were febrile UTI in 6 of29 cases and double-J dislocation in 3 of 29 cases.

CONCLUSION

During the observation period, the success rate of temporary double-J in urodynamically relevant obstruction was relatively high. However, urinary tract infections and a complex disease course due to renal stent dislocation, as well as the need for repeated anesthesia and radiation exposure, should be taken into account. Hence, we do not recommend double-J stents placement in all children with congenital hydronephrosis; it may be useful in selected cases.

A new recommendation for febrile urinary tract infection in children aged 2-24 months: Tepecik UTI Guideline-2

AIM

Urinary tract infections (UTIs) represent a common febrile illness in infancy. The study compared two UTI guidelines in terms of number of imaging studies, presence of parenchymal damage and radiation exposure in patients with the first febrile UTI between 2 and 24 months of age.

METHOD

The results of Tepecik UTI Guideline-1 used until 2012 (Group 1, n = 105) were retrospectively compared with Tepecik UTI Guideline-2 (Group 2) used after 2013. In Group 1, urinary tract ultrasonography (US), dimercaptosuccinic acid (DMSA) and voiding cystourethrography (VCUG) were made in all patients. In Group 2, if the US result was abnormal, patients were evaluated with VCUG and DMSA. If the US was normal, only DMSA was performed. If the DMSA was abnormal, the VCUG was undergone (n: 43, 40.9%).

RESULTS

The abnormal VCUG detection rate was 69.2% in Group 1 and 30.8% in Group 2 (p = 0.09). Sensitivity and specificity of US in the diagnosis of vesicoureteral reflux (VUR) was 15.9% and 96.7% in Group 1 and 61.5% and 70.5% in Group 2, respectively. Abnormal DMSA findings were observed among 33.3% (Groups 1) and 66.7% (Groups 2) subjects, respectively (p > 0.05). The median radiation exposure (500 mrem) of patients in Group 1 was statistically significantly higher than those in Group 2 (200 mrem) (p < 0.001).

CONCLUSION

The VCUG should not be the first examination to be considered in such patients. We think that Tepecik UTI Guideline-2 reduces unnecessary invasive procedure and radiation exposure and not missed VUR in the management of children with UTI at 2-24 months. Needs prospective follow-up studies before considering this recommendation.

Urine neutrophil gelatinase-associated lipocalin in girls with recurrent urinary tract infections

BACKGROUND

Children who experience more than one urinary tract infection (UTI) are at increased risk of kidney scarring due to their UTIs. Girls are at especially high risk for developing kidney scarring as a result of recurrent UTIs. Prior work suggested that neutrophil gelatinase-associated lipocalin (NGAL) may be lower in children with recurrent UTI compared with those without. The objective of this work was to compare urine NGAL concentrations in matched urine samples in girls with single and recurrent UTIs.

METHODS

Girls less than 6 years of age who presented with signs and symptoms of a UTI were eligible for enrollment. Both acute, obtained from residual urine collected as part of their clinical evaluation, and follow-up urine samples, obtained after the completion of antibiotics when the patient was in their usual state of health, were collected from patients. Acute and follow-up urine NGAL concentrations were compared between girls with single and recurrent UTIs, as well as those with negative cultures who served as controls.

RESULTS

Seventy girls were included in this study, 6 controls, 43 single UTIs, and 20 girls with recurrent UTIs. Patients in the control group had lower median acute NGAL concentrations than either those with single or recurrent UTI. There were no differences in either acute or follow-up urine NGAL concentrations between those with single and recurrent UTIs.

CONCLUSION

In this cohort of girls less than 6 years of age, there is no difference in urine NGAL concentrations between those with single and recurrent UTIs.

Does endoscopic sclerotherapy in filarial chyluria affect renal function and morphology? A prospective study using dimercaptosuccinic acid renal scan

Objective

To look for change in relative renal function and document renal scarring following endoscopic renal pelvic instillation sclerotherapy (RPIS) in patients with chyluria by dimercaptosuccinic acid (DMSA) renal scan.

Methods

A prospective study was performed between November 2015 and September 2016. All patients with biochemically documented chyluria who underwent RPIS using either 1%-silver nitrate or 0.1%-povidine iodine were included. Patients received either 3-, 6- or 9-doses. DMSA renal scan was performed before and 2–3 months after sclerotherapy.

Results

Of the 34 patients, 22 were males. Mean age was 41.08 ± 16.64 years (range, 15–70 years). Thirty-two patients (94.1%) responded to therapy while two did not respond even after 9-doses. Average follow-up was 8.94 ± 3.70 months. The mean relative renal function (pre-instillation) of normal kidney was 50.76% ± 3.55% while that of affected renal unit (side of instillation) was 49.20% ± 3.44% (range, 43.0%–61.0%). After instillation therapy, the mean relative renal function of normal side was 52.26% ± 3.57% while that of affected renal unit was 47.50% ± 3.56% (range, 41.0%–54.0%). The relative renal function did not change >5% from the baseline value in any patient except one (in which the differential function increased paradoxically by 12%). Two patients developed renal scar in post-instillation renal scan.

Conclusion

Endoscopic sclerotherapy in chyluria is safe and effective. The relative renal function does not deteriorate by more than 5%. There is a small risk of development of renal scar. More studies involving larger number of patients are needed to answer this dilemma.

Prediction of renal cortical defect and scar using neutrophil-to-lymphocyte ratio in children with febrile urinary tract infection

AIM

This study is aimed to evaluate the predictive value of the neutrophil-to-lymphocyte ratio (NLR) for cortical defect on initial and follow-up Tc-99m dimercaptosuccinic acid (DMSA) scan in children with the first febrile urinary tract infection (UTI).

METHODS

We retrospectively enrolled 179 children with the first febrile UTI who underwent DMSA scan and laboratory tests. In patients with abnormal DMSA scan findings, follow-up DMSA scan was performed at least 6 months after the initial scan. All DMSA scans were classified as negative and positive cortical defects. Multiple logistic regression analyses were performed to identify the risk factors for cortical defect on initial and follow-up DMSA scan.

RESULTS

Cortical defects on initial DMSA scan were noted in 133 patients. Vesicoureteral reflux (VUR), white blood cell count, absolute neutrophil count, NLR, and serum C-reactive protein level were independent predictive factors for positive cortical defect on initial DMSA scan (p < 0.050). On follow-up DMSA scan, 24 of the 133 patients showed persistent cortical defects, and only VUR was significantly associated with persistent cortical defect (p = 0.002). In 84 patients who showed cortical defect on initial scan and absence of VUR, only NLR was significantly associated with persistent cortical defect on follow-up scan (p = 0.025).

CONCLUSION

NLR was significantly associated with persistent cortical defect on follow-up DMSA scan in patients without VUR, as well as positive cortical defect on initial scan.

Dimercaptosuccinic acid scan or ultrasound in screening for vesicoureteral reflux among children with urinary tract infections

BACKGROUND

There is considerable interest in detecting vesicoureteral reflux (VUR) because its presence, especially when severe, has been linked to an increased risk of urinary tract infections and renal scarring. Voiding cystourethrography (VCUG), also known as micturating cystourethrography, is the gold standard for the diagnosis of VUR, and the grading of its severity. Because VCUG requires bladder catheterisation and exposes children to radiation, there has been a growing interest in other screening strategies that could identify at-risk children without the risks and discomfort associated with VCUG.

OBJECTIVES

The objective of this review is to evaluate the accuracy of two alternative imaging tests - the dimercaptosuccinic acid renal scan (DMSA) and renal-bladder ultrasound (RBUS) - in diagnosing VUR and high-grade VUR (Grade III-V VUR).

SEARCH METHODS

We searched MEDLINE, EMBASE, BIOSIS, and the Cochrane Register of Diagnostic Test Accuracy Studies from 1985 to 31 March 2016. The reference lists of relevant review articles were searched to identify additional studies not found through the electronic search.

SELECTION CRITERIA

We considered published cross-sectional or cohort studies that compared the results of the index tests (DMSA scan or RBUS) with the results of radiographic VCUG in children less than 19 years of age with a culture-confirmed urinary tract infection.

DATA COLLECTION AND ANALYSIS

Two authors independently applied the selection criteria to all citations and independently abstracted data. We used the bivariate model to calculate summary sensitivity and specificity values.

MAIN RESULTS

A total of 42 studies met our inclusion criteria. Twenty studies reported data on the test performance of RBUS in detecting VUR; the summary sensitivity and specificity estimates were 0.44 (95% CI 0.34 to 0.54) and 0.78 (95% CI 0.68 to 0.86), respectively. A total of 11 studies reported data on the test performance of RBUS in detecting high-grade VUR; the summary sensitivity and specificity estimates were 0.59 (95% CI 0.45 to 0.72) and 0.79 (95% CI 0.65 to 0.87), respectively. A total of 19 studies reported data on the test performance of DMSA in detecting VUR; the summary sensitivity and specificity estimates were 0.75 (95% CI 0.67 to 0.81) and 0.48 (95% CI 0.38 to 0.57), respectively. A total of 10 studies reported data on the accuracy of DMSA in detecting high-grade VUR. The summary sensitivity and specificity estimates were 0.93 (95% CI 0.77 to 0.98) and 0.44 (95% CI 0.33 to 0.56), respectively.

AUTHORS' CONCLUSIONS

Neither the renal ultrasound nor the DMSA scan is accurate enough to detect VUR (of all grades). Although a child with a negative DMSA test has an < 1% probability of having high-grade VUR, performing a screening DMSA will result in a large number of children falsely labelled as being at risk for high-grade VUR. Accordingly, the usefulness of the DMSA as a screening test for high-grade VUR should be questioned.

Prevalência de pielonefrite aguda e incidência de cicatriz renal em crianças menores de dois anos de idade com infecção do trato urinário avaliadas por cintilografia renal com 99mTc-DMSA: a experiência de um hospital universitário

OBJETIVO: Calcular as frequências de pielonefrite aguda e cicatriz renal em pacientes menores de dois anos com cintilografia renal com 99mTc-DMSA com primeiro quadro de infecção do trato urinário em hospital universitário brasileiro, comparando com dados da literatura internacional. MATERIAIS E MÉTODOS: Foram revisados laudos cintilográficos de crianças menores de dois anos de idade que realizaram cintilografia renal com 99mTc-DMSA em um hospital universitário no Rio Grande do Sul, entre 2006 e 2009, para pesquisa de pielonefrite aguda/cicatriz renal. Revisaram-se a presença de refluxo vesicoureteral, o uso precoce de antibiótico, e a presença de comorbidades que constassem nos prontuários eletrônicos. Calculou-se a amostra com base num estudo de revisão sistemática e obteve-se um mínimo de 147 pacientes. Excluíram-se pacientes sem registro eletrônico. RESULTADOS: Cento e cinquenta e sete crianças preencheram critérios de inclusão do estudo, 48 tiveram pielonefrite aguda e 8 destas apresentaram cicatriz renal. Nem a idade nem o gênero dos pacientes apresentaram associação significativa com pielonefrite aguda (p = 0,405 e p = 0,124, respectivamente). Não houve diferença estatística nas associações de refluxo vesicoureteral e pielonefrite aguda (p = 1,0) e outras comorbidades (p = 0,470) e em relação ao uso precoce de antibiótico com pielonefrite aguda (p = 0,130) e cicatriz renal (p = 0,720). CONCLUSÃO: As frequências de pielonefrite aguda e cicatriz renal obtidas concordam com os resultados da maioria dos estudos publicados.

Risk factors for renal scar formation in infants with first episode of acute pyelonephritis: a prospective clinical study

PURPOSE

We prospectively determined the risk factors for renal scar formation after the first episode of acute pyelonephritis as confirmed on dimercapto-succinic acid scintigraphy in children younger than 1 year.

MATERIALS AND METHODS

A total of 213 infants with acute pyelonephritis were enrolled in the study. Infants with urological abnormalities other than vesicoureteral reflux were excluded from analysis. Followup scanning was performed 6 months after acute pyelonephritis and voiding cystourethrography was performed after the acute phase of infection. Possible risk factors were evaluated including gender, peak fever, duration of fever before and after treatment with antibiotics, white blood cell count, C-reactive protein concentration, presence of vesicoureteral reflux and reflux grade.

RESULTS

Six months after acute pyelonephritis 37 of 213 (17.4%) infants and 41 of 248 (16.5%) renal units with acute photon defects on initial dimercapto-succinic acid scintigraphy had renal scars. The rates of scar formation were significantly higher in infants with vesicoureteral reflux than in those without (39.4% vs 7.5%, p <0.001, OR 9.433) and in renal units with vesicoureteral reflux than in those without (39.4% vs 8.2%, p <0.001, OR 7.237). Renal scar formation was related to reflux grade (none-8.2%, grade I-20%, grade II-22.7%, grade III-40%, grade IV-70%, grade V-55.6%, p <0.001) but not to any other clinical or laboratory variables.

CONCLUSIONS

The presence of vesicoureteral reflux was the only independent risk factor for renal scar formation after acute pyelonephritis in infants. The prevalence of renal scarring was significantly correlated with reflux grade. Voiding cystourethrography is necessary in infants after the first acute pyelonephritis episode is confirmed on dimercapto-succinic acid renal scintigraphy.

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.

Vesicoureteral reflux and urinary tract infection: evolving practices and current controversies in pediatric imaging

OBJECTIVE

Pediatric patients with urinary tract infection (UTI) undergo imaging tests to detect vesicoureteral reflux (VUR) in the belief that VUR correlates to risk of renal scarring. This article describes recent evolution and controversies in the management of UTI and VUR.

CONCLUSION

Multitechnique imaging of UTI and VUR is complex and controversial. Evolution in practice patterns is motivated by the desire to rationally minimize unnecessary interventions and radiation exposure. Ongoing evidence-based research is needed to further improve practice guidelines.

Screening for CKD in children: a global controversy

This review addresses the relevance of urinary screening for chronic kidney disease (CKD) in children. Ambiguity about screening children exists because of the uncertainty as to whether early detection of renal disorders in childhood will lead to effective interventions and reduction in the number of individuals who subsequently progress to ESRD. A related concern is whether the adoption of urinary screening programs is cost effective. The most common method that is used for screening children for CKD involves the measurement of spot samples of urine for hematuria and or proteinuria. Although mass screening is now well established in Japan, Taiwan, and Korea, there appears to be movement away from mass screening to detect CKD in children and adolescents in North America and Europe. In December 2007, the American Academy of Pediatrics published their latest recommendations, in which no urinalyses were recommended at any age during childhood. The second issue addressed in this review is the reporting of estimated glomerular filtration rates (GFR) in children by clinical laboratories.

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.

Nuclear imaging in the genitourinary tract: recent advances and future directions

For almost three decades, noninvasive radionuclide procedures for the evaluation of renal disease have been important components of nuclear medicine practice. With the introduction of new imaging agents and procedures, these techniques can provide valuable data on perfusion and function of individual kidneys. In general, these procedures are easy to perform and carry a low radiation burden and sedation is not required. Moreover, radionuclide imaging of the genitourinary tract has become an invaluable asset to clinicians in the evaluation of renal parenchyma and urologic abnormalities.

Antibiotic treatment for pyelonephritis in children: multicentre randomised controlled non-inferiority trial

OBJECTIVE

To compare the efficacy of oral antibiotic treatment alone with treatment started parenterally and completed orally in children with a first episode of acute pyelonephritis.

DESIGN

Multicentre, randomised controlled, open labelled, parallel group, non-inferiority trial.

SETTING

28 paediatric units in north east Italy.

PARTICIPANTS

502 children aged 1 month to <7 years with clinical pyelonephritis.

INTERVENTION

Oral co-amoxiclav (50 mg/kg/day in three doses for 10 days) or parenteral ceftriaxone (50 mg/kg/day in a single parenteral dose) for three days, followed by oral co-amoxiclav (50 mg/kg/day in three divided doses for seven days). Main outcomes measures Primary outcome was the rate of renal scarring. Secondary measures of efficacy were time to defervescence (<37 degrees C), reduction in inflammatory indices, and percentage with sterile urine after 72 hours. An exploratory subgroup analysis was conducted in the children in whom pyelonephritis was confirmed by dimercaptosuccinic acid (DMSA) scintigraphy within 10 days after study entry.

RESULTS

Intention to treat analysis showed no significant differences between oral (n=244) and parenteral (n=258) treatment, both in the primary outcome (scarring scintigraphy at 12 months 27/197 (13.7%) v 36/203 (17.7%), difference in risk -4%, 95% confidence interval -11.1% to 3.1%) and secondary outcomes (time to defervescence 36.9 hours (SD 19.7) v 34.3 hours (SD 20), mean difference 2.6 (-0.9 to 6.0); white cell count 9.8x10(9)/l (SD 3.5) v 9.5x10(9)/l (SD 3.1), mean difference 0.3 (-0.3 to 0.9); percentage with sterile urine 185/186 v 203/204, risk difference -0.05% (-1.5% to 1.4%)). Similar results were found in the subgroup of 278 children with confirmed acute pyelonephritis on scintigraphy at study entry.

CONCLUSIONS

Treatment with oral antibiotics is as effective as parenteral then oral treatment in the management of the first episode of clinical pyelonephritis in children.

TRIAL REGISTRATION

Clinical Trials NCT00161330 [ClinicalTrials.gov].