Study of serum and urinary markers of the reninangiotensin-aldosterone system in myelomeningocele patients with renal injury detected by DMSA

ABSTRACT Introduction: The Renin-Angiotensin-Aldosterone System (RAAS) has been suggested as a possible marker of renal injury in chronic diseases. This study proposes to analyze the serum and urinary markers of the RAAS in myelomeningocele patients with renal function abnormalities detected on DMSA. Material and Methods: Seventeen patients followed in our institution that presented with renal injury on DMSA. We review nephrologic and urologic clinical aspects and evaluated ultrassonagraphy, voiding urethrocystography and urodynamics. Urinary and serum samples were collected to evaluate possible correlations of renal lesions with RAAS. Control group urine and serum samples were also sent for analysis. Results: Serum ACE 2 activity means in relation to urodynamic findings were the only values that had a statistically significant difference (p = 0.040). Patients with normal bladder pattern presented higher ACE 2 levels than the high risk group. Statistical analysis showed that the study group (SG) had a significantly higher mean serum ACE than the CG. The means of ACE 2 and urinary ACE of the SG and CG were not statistically different. The ROC curve for serum ACE values had a statistically significant area for case and non-case differentiation, with 100% sensitivity and 53% specificity for values above 60.2 mg/dL. No statistically significant areas were observed in relation to ACE 2 and urinary ACE values between SG and CG. Conclusion: The analysis of serum ACE, ACE 2 and urinary ACE were not significant in patients with myelomeningocele and neurogenic bladder with renal injury previously detected by renal DMSA.

The examination of the nephroprotective effect of montelukast sodium and N-acetylcysteine in renal ischemia with dimercaptosuccinic acid imaging in a placebo-controlled rat model

Abstract Purpose To determine the nephroprotective effect of NAC and Montelukast Sodium administration against the development of renal damage associated with long warm renal ischemia. Methods Twenty-seven rats were randomly divided into 3 study groups, which received NAC, montelukast and placebo, and 3 rats were included in the sham-treated control group. Medications were given 3 days before the procedure. DMSA renal scintigraphy was performed before and after surgery. The right renal pedicle was occluded for 45 min to induce ischemia and then subjected to reperfusion for 6 h (I/R groups). Results On pathological examination, the mean pathological scores of the montelukast and NAC groups were significantly lower than those of the placebo group. (p <0.05). In biochemical examination, significant differences were found in all parameter levels between the placebo group and the montelukast and NAC groups. (p <0.05) When postoperative DMSA renal scintigraphy measurements and renal function levels were compared, significant differences were found between the montelukast and NAC groups and the placebo and sham groups. Conclusion The administration of NAC and montelukast sodium was seen to have a nephroprotective effect against the development of renal damage associated with warm renal ischemia.

A Renal Size Discrepancy among the Findings of Renal Sonogram in Children with Their First Episode of Pyelonephritis is One of the Useful Parameters to Predict the Presence of Cortical Defects on the Acute DMSA Renal Scan

PURPOSE: We investigated whether a renal size discrepancy on a renal sonogram (US) in children with febrile urinary tract infection (UTI) was correlated with the presence of cortical defects on their dimercaptosuccinic acid (DMSA) renal scan. METHODS: We examined 911 children who were admitted consecutively to our hospital with their first episode of febrile UTI from March 2001 to September 2014. All enrolled children underwent a US and DMSA scan during admission. According to the US findings, including the renal size discrepancy, data were compared between children with positive and negative DMSA scan results. A positive DMSA scan result was defined as reduced or absent tracer localization and indistinct margins that did not deform the renal contour. RESULTS: Mean renal lengths of the right and left kidneys were larger in children with positive DMSA scan results than in children with negative DMSA scan results (63.2±11.3 mm vs. 58.4±7.8 mm, P<0.001; 64.9±11.2 mm vs. 59.9±7.9 mm, P<0.001; respectively). A significant difference was observed in both renal lengths between children with positive and negative DMSA scan results (4.6±3.8 mm vs. 3.3±2.6 mm, P<0.001). A multiple logistic regression analysis, revealed that a small kidney, cortical thinning, and a renal length discrepancy on US findings were significant factors for predicting the presence of cortical defects on an acute DMSA scan [P=0.028, 95% confidence interval (CI) 1.054–2.547; P=0.004, 95% CI 1.354–4.810; P<0.001, 95% CI 1.077–1.190, respectively]. CONCLUSION: In conclusion, a renal size discrepancy on US findings in children with their first episode of febrile UTI was a helpful tool for predicting the presence of cortical defects on an acute DMSA scan.

Radiation nephritis: (99m)Tc hydroxydiphosphonate bone scan, (99m)Tc dimercaptosuccinic acid renal scan, and ¹⁸F-FDG PET/CT findings

No abstract available.

Comparison of 99mTc-DMSA Renal Scan and Power Doppler Ultrasonography for the Detection of Acute Pyelonephritis and Vesicoureteral Reflux

PURPOSE: Urinary tract infection (UTI) is one of the common infectious diseases in children. Several imaging modalities can be used to confirm the presence of acute pyelonephritis (APN). Among them the 99mTcdimercaptosuccinic acid renal scan (DMSA scan) is used as a gold standard for diagnosis. Ultrasonography technology is evolving. Therefore, in this study, we investigated the sensitivity and specificity of Power Doppler ultrasonography (PDU) compared to the results from the previous study. METHODS: There were 260 patients included in this study, aged between 1 and 12 months old. The patients were admitted to the Yeungnam University Medical Center between January 2008 and December 2015. All patients underwent both DMSA scan and PDU within 5days of admission. Voiding cystourethrography (VCUG) was performed in 195 patients with abnormal DMSA scan or PDU. RESULTS: The diagnostic sensitivity of APN using PDU was 45.5% and specificity was 85.5% in 260 patients following detection of a defect on DMSA scan that was defined as APN. The diagnostic sensitivity and specificity of PDU for VUR were 65.5 % and 60.1%, respectively. The diagnostic sensitivity and specificity of DMSA scan for VUR were 95.7% and 14.1%, respectively. CONCLUSION: PDU has a high specificity but low sensitivity, so there are limitations in using it to replace a DMSA scan for the diagnosis of APN in children. DMSA scan and PDU have different sensitivity and specificity in diagnosis of VUR, respectively. Therefore, we suggest that the sensitivity and specificity of each test can be helpful in diagnosing APN and VUR when used in conjunction.

Plasma Neutrophil Gelatinase-Associated Lipocalin as a Predictor of Renal Parenchymal Involvement in Infants With Febrile Urinary Tract Infection: A Preliminary Study

BACKGROUND: Urinary tract infection (UTI) is the most common bacterial infection in infants. Renal parenchymal involvement is an important prognostic factor; however, early detection of parenchymal involvement in UTI may be difficult during infancy. This study aimed to assess whether a recently established biomarker of UTI, neutrophil gelatinase-associated lipocalin (NGAL), can serve as a useful marker for the detection of cortical defects (CD) and to determine the appropriate diagnostic cut-off value of NGAL in infants with febrile UTI. METHODS: Infants hospitalized for febrile UTI were divided into two groups according to the presence of cortical defects on dimercaptosuccinic acid (DMSA) scintigraphy. Among 64 enrolled infants, 43 (67%) had CD (UTI-CD) and 21 (33%) had no CD (UTI-ND). The white blood cell count, C-reactive protein, and plasma NGAL (pNGAL) levels were determined before antibiotic therapy and compared between the two groups. RESULTS: pNGAL level was significantly higher in the UTI-CD group than in the UTI-ND group (340 µg/L vs 214 µg/L, P=0.002). Multivariate analysis showed that pNGAL level was the only independent predictor of CD (odds ratio 2.759, P=0.039). In the ROC curve analysis, pNGAL showed the highest area under the curve (0.745; 95% confidence interval, 0.561–0.821; P=0.014). The appropriate cut-off value of pNGAL was 267 µg/L (sensitivity, 72.1%; specificity, 71.4%). CONCLUSIONS: pNGAL was found to be a useful marker for early prediction of renal parenchymal involvement in infants with febrile UTI.

Clinical Characteristics and Outcomes of the First Episode of Urinary Tract Infection in Neonates and Infants Younger than 2 Months of Age

PURPOSE: The American Academy of Pediatrics provides guidelines for managing febrile urinary tract infection (UTI) in infants and children 2-24 months old, but little guidance is offered regarding UTIs in those younger than 8 weeks of age. The definition of UTI is unclear and whether to proceed with micturating cystourethrography (MCUG) or 99mtechnetium-dimercaptosuccinic acid (DMSA) scintigraphy scan in this age group is controversial. METHODS: We retrospectively analyzed 29 neonates and infants younger than 2 months of age who underwent late DMSA scans 9 months following the first episode of febrile or symptomatic UTI between July 2009 and June 2016. RESULTS: In total, 192 children aged 0-24 months underwent ultrasound and DMSA scans (MCUG in 174/192). Neonates and infants younger than 2 months of age were significantly less likely to develop fever, and had a lower fever peak, shorter duration of fever before admission and after starting antibiotics, longer hospitalization period, lower C-reactive protein, and greater incidence of non-Escherichia coli infection. There was no difference in pyuria response at diagnosis. The prevalence rates of an ultrasound abnormality (28%), vesicoureteral reflux (28%), UTI recurrence (38%), and renal scarring (10%) in infants younger than 8 weeks of age were similar to those in children 2-24 months old. CONCLUSION: Neonates and infants younger than 2 months of age with UTI warrant special consideration because the fever response used for diagnosis in older children may be absent or blunted. Clinical guideline is needed for the diagnosis and management of UTI in this age group.

Clinical Characteristics and Outcomes of the First Episode of Urinary Tract Infection in Neonates and Infants Younger than 2 Months of Age

PURPOSE: The American Academy of Pediatrics provides guidelines for managing febrile urinary tract infection (UTI) in infants and children 2-24 months old, but little guidance is offered regarding UTIs in those younger than 8 weeks of age. The definition of UTI is unclear and whether to proceed with micturating cystourethrography (MCUG) or 99mtechnetium-dimercaptosuccinic acid (DMSA) scintigraphy scan in this age group is controversial. METHODS: We retrospectively analyzed 29 neonates and infants younger than 2 months of age who underwent late DMSA scans 9 months following the first episode of febrile or symptomatic UTI between July 2009 and June 2016. RESULTS: In total, 192 children aged 0-24 months underwent ultrasound and DMSA scans (MCUG in 174/192). Neonates and infants younger than 2 months of age were significantly less likely to develop fever, and had a lower fever peak, shorter duration of fever before admission and after starting antibiotics, longer hospitalization period, lower C-reactive protein, and greater incidence of non-Escherichia coli infection. There was no difference in pyuria response at diagnosis. The prevalence rates of an ultrasound abnormality (28%), vesicoureteral reflux (28%), UTI recurrence (38%), and renal scarring (10%) in infants younger than 8 weeks of age were similar to those in children 2-24 months old. CONCLUSION: Neonates and infants younger than 2 months of age with UTI warrant special consideration because the fever response used for diagnosis in older children may be absent or blunted. Clinical guideline is needed for the diagnosis and management of UTI in this age group.

Clinical implications of DMSA Scan in Childhood Acute Pyelonephritis

PURPOSE: This study aimed to evaluate the relationships between 99mTecnicium-dimercaptosuccinic acid (DMSA) scan findings and clinical parameters including age and fever duration. METHODS: The positive rates for abnormal DMSA scans were analyzed according to the age of patients, fever duration prior to admission, and total fever duration. DMSA scan findings were divided into 3 categories: single defect, multifocal defects, and discrepant defects. We evaluated the detection rates of vesicoureteral reflux according to DMSA scan lesions. RESULTS: Among a total 320 cases, 141 (44.1%) had abnormal DMSA scans. The infant group (0-1 year of age) had a shorter total fever duration, and a lower C-reactive protein (CRP) value and DMSA positive rate (39.8% vs. 60.6%, P=0.002) compared to children group (2-15 years of age). Patients with abnormal scans had a longer total fever duration and higher CRP compared to those with normal scans. The positivity rate of abnormal scans did not differ between the patients with a short fever duration prior to admission of ≤2 days and those with longer fever duration of ≥3 days. However, patients with longer total fever duration had a higher rate of abnormal DMSA scans (P=0.02). Among cases with a single defect, multifocal defects, and discrepant defects, vesicoureteral reflux was observed in 22.4%, 60% and 70.6% of cases, respectively (P=0.004). CONCLUSION: Although DMSA scan has limitations in early diagnosis, DMSA scan findings may aid in the prediction of the severity of systemic inflammation and detection of vesicoureteral reflux.

Clinical Efficacy of a Top-down Approach for Children with a First Febrile Urinary Tract Infection

PURPOSE: The aim of this study was to determine the clinical characteristics, frequency of renal abnormalities and benefits of a top-down approach in children with their first febrile urinary tract infection (UTI). METHODS: We reviewed 308 patients retrospectively who were admitted to Yeungnam University Hospital and were treated for their first febrile UTI from February 2006 to December 2013. We performed a comparative analysis of laboratory findings and results of imaging techniques including a Tc-99m dimercaptosuccinic acid (DMSA) renal scan. RESULTS: Among the patients, 69% (213/308) were males, and 90% (277/308) had their first UTI episode during infancy. A DMSA renal scan was performed on all patients, and showed positive findings in 60% (184/308) of cases. Laboratory indices of inflammation were significantly higher in the DMSA-positive group (P<0.05). There was a statistically significant difference in the age distribution between the two groups. In the DMSA-positive group, 165 patients underwent voiding cystourethrography (VCUG), and 58 (35%) cases demonstrated vesicoureteral reflux. In total, 110 patients in the DMSA-positive group, underwent repeat scanning at 6 months; 33 children (30%) demonstrated static scarring, but 77 (70%) had improved completely. The concordance of the ultrasonography (US) and VCUG was low. Older patients had more renal scarring. CONCLUSION: DMSA is a sensitive method for assessing the severity of inflammation and kidney injury. However, the ability of US to predict renal parenchymal damage was limited. A top-down approach in children with their first febrile UTI showed significant value.

Clinical implications of DMSA Scan in Childhood Acute Pyelonephritis

PURPOSE: This study aimed to evaluate the relationships between 99mTecnicium-dimercaptosuccinic acid (DMSA) scan findings and clinical parameters including age and fever duration. METHODS: The positive rates for abnormal DMSA scans were analyzed according to the age of patients, fever duration prior to admission, and total fever duration. DMSA scan findings were divided into 3 categories: single defect, multifocal defects, and discrepant defects. We evaluated the detection rates of vesicoureteral reflux according to DMSA scan lesions. RESULTS: Among a total 320 cases, 141 (44.1%) had abnormal DMSA scans. The infant group (0-1 year of age) had a shorter total fever duration, and a lower C-reactive protein (CRP) value and DMSA positive rate (39.8% vs. 60.6%, P=0.002) compared to children group (2-15 years of age). Patients with abnormal scans had a longer total fever duration and higher CRP compared to those with normal scans. The positivity rate of abnormal scans did not differ between the patients with a short fever duration prior to admission of ≤2 days and those with longer fever duration of ≥3 days. However, patients with longer total fever duration had a higher rate of abnormal DMSA scans (P=0.02). Among cases with a single defect, multifocal defects, and discrepant defects, vesicoureteral reflux was observed in 22.4%, 60% and 70.6% of cases, respectively (P=0.004). CONCLUSION: Although DMSA scan has limitations in early diagnosis, DMSA scan findings may aid in the prediction of the severity of systemic inflammation and detection of vesicoureteral reflux.

Clinical Efficacy of a Top-down Approach for Children with a First Febrile Urinary Tract Infection

PURPOSE: The aim of this study was to determine the clinical characteristics, frequency of renal abnormalities and benefits of a top-down approach in children with their first febrile urinary tract infection (UTI). METHODS: We reviewed 308 patients retrospectively who were admitted to Yeungnam University Hospital and were treated for their first febrile UTI from February 2006 to December 2013. We performed a comparative analysis of laboratory findings and results of imaging techniques including a Tc-99m dimercaptosuccinic acid (DMSA) renal scan. RESULTS: Among the patients, 69% (213/308) were males, and 90% (277/308) had their first UTI episode during infancy. A DMSA renal scan was performed on all patients, and showed positive findings in 60% (184/308) of cases. Laboratory indices of inflammation were significantly higher in the DMSA-positive group (P<0.05). There was a statistically significant difference in the age distribution between the two groups. In the DMSA-positive group, 165 patients underwent voiding cystourethrography (VCUG), and 58 (35%) cases demonstrated vesicoureteral reflux. In total, 110 patients in the DMSA-positive group, underwent repeat scanning at 6 months; 33 children (30%) demonstrated static scarring, but 77 (70%) had improved completely. The concordance of the ultrasonography (US) and VCUG was low. Older patients had more renal scarring. CONCLUSION: DMSA is a sensitive method for assessing the severity of inflammation and kidney injury. However, the ability of US to predict renal parenchymal damage was limited. A top-down approach in children with their first febrile UTI showed significant value.

Predictors of High-grade Vesicoureteral Reflux in Children with Febrile Urinary Tract Infections

PURPOSE: This study aimed to investigate clinical and radiological factors that may predict high-grade vesicoureteral reflux (VUR) in patients with febrile urinary tract infection (UTI). METHODS: We retrospectively analyzed medical records of 446 patients diagnosed with febrile UTI from March 2008 to February 2017. All patients underwent renal-bladder ultrasonography (RBUS), 99mTc dimercaptosuccinic acid (DMSA) renal scan, and voiding cystourethrography (VCUG), and were divided in to 3 groups: a high-grade VUR group (n=53), a low-grade VUR group (n=28), and a group without VUR (n=365). RESULTS: The recurrence and non-Escherichia coli infection rates in febrile UTI were significantly higher in the high-grade VUR group than in the other two groups (P<0.05). RBUS showed that hydronephrosis and ureter dilatation were more frequent in the high-grade VUR group than in the other groups (P<0.05). In the high-grade VUR group, a renal cortical defect was more likely to appear as multiple defects, and the difference in bilateral renal scan uptake between both kidneys was larger than in the other two groups (P<0.001). CONCLUSION: Recurrent UTI, non-E. coli UTI, abnormal findings on RBUS such as hydronephrosis and ureter dilatation, and abnormal findings in the DMSA renal scan such as multiple renal cortical defects and greater uptake difference were associated with high-grade VUR. VCUG should be selectively performed when RBUS and/or DMSA renal scan reveal significant abnormalities.

Predictors of High-grade Vesicoureteral Reflux in Children with Febrile Urinary Tract Infections

PURPOSE: This study aimed to investigate clinical and radiological factors that may predict high-grade vesicoureteral reflux (VUR) in patients with febrile urinary tract infection (UTI). METHODS: We retrospectively analyzed medical records of 446 patients diagnosed with febrile UTI from March 2008 to February 2017. All patients underwent renal-bladder ultrasonography (RBUS), 99mTc dimercaptosuccinic acid (DMSA) renal scan, and voiding cystourethrography (VCUG), and were divided in to 3 groups: a high-grade VUR group (n=53), a low-grade VUR group (n=28), and a group without VUR (n=365). RESULTS: The recurrence and non-Escherichia coli infection rates in febrile UTI were significantly higher in the high-grade VUR group than in the other two groups (P<0.05). RBUS showed that hydronephrosis and ureter dilatation were more frequent in the high-grade VUR group than in the other groups (P<0.05). In the high-grade VUR group, a renal cortical defect was more likely to appear as multiple defects, and the difference in bilateral renal scan uptake between both kidneys was larger than in the other two groups (P<0.001). CONCLUSION: Recurrent UTI, non-E. coli UTI, abnormal findings on RBUS such as hydronephrosis and ureter dilatation, and abnormal findings in the DMSA renal scan such as multiple renal cortical defects and greater uptake difference were associated with high-grade VUR. VCUG should be selectively performed when RBUS and/or DMSA renal scan reveal significant abnormalities.

Usefulness of neutrophil-lymphocyte ratio in young children with febrile urinary tract infection / 소아과

PURPOSE: Acute pyelonephritis (APN) is a serious bacterial infection that can cause renal scarring in children. Early identification of APN is critical to improve treatment outcomes. The neutrophil-lymphocyte ratio (NLR) is a prognostic marker of many diseases, but it has not yet been established in urinary tract infection (UTI). The aim of this study was to determine whether NLR is a useful marker to predict APN or vesicoureteral reflux (VUR). METHODS: We retrospectively evaluated 298 pediatric patients (age≤36 months) with febrile UTI from January 2010 to December 2014. Conventional infection markers (white blood cell [WBC] count, erythrocyte sedimentation rate [ESR], C-reactive protein [CRP]), and NLR were measured. RESULTS: WBC, CRP, ESR, and NLR were higher in APN than in lower UTI (P<0.001). Multiple logistic regression analyses showed that NLR was a predictive factor for positive dimercaptosuccinic acid (DMSA) defects (P<0.001). The area under the receiver operating characteristic (ROC) curve was high for NLR (P<0.001) as well as CRP (P<0.001) for prediction of DMSA defects. NLR showed the highest area under the ROC curve for diagnosis of VUR (P<0.001). CONCLUSION: NLR can be used as a diagnostic marker of APN with DMSA defect, showing better results than those of conventional markers for VUR prediction.

Usefulness of neutrophil-lymphocyte ratio in young children with febrile urinary tract infection / 소아과

PURPOSE: Acute pyelonephritis (APN) is a serious bacterial infection that can cause renal scarring in children. Early identification of APN is critical to improve treatment outcomes. The neutrophil-lymphocyte ratio (NLR) is a prognostic marker of many diseases, but it has not yet been established in urinary tract infection (UTI). The aim of this study was to determine whether NLR is a useful marker to predict APN or vesicoureteral reflux (VUR). METHODS: We retrospectively evaluated 298 pediatric patients (age≤36 months) with febrile UTI from January 2010 to December 2014. Conventional infection markers (white blood cell [WBC] count, erythrocyte sedimentation rate [ESR], C-reactive protein [CRP]), and NLR were measured. RESULTS: WBC, CRP, ESR, and NLR were higher in APN than in lower UTI (P<0.001). Multiple logistic regression analyses showed that NLR was a predictive factor for positive dimercaptosuccinic acid (DMSA) defects (P<0.001). The area under the receiver operating characteristic (ROC) curve was high for NLR (P<0.001) as well as CRP (P<0.001) for prediction of DMSA defects. NLR showed the highest area under the ROC curve for diagnosis of VUR (P<0.001). CONCLUSION: NLR can be used as a diagnostic marker of APN with DMSA defect, showing better results than those of conventional markers for VUR prediction.

New Insights for Febrile Urinary Tract Infection (Acute Pyelonephritis) in Children

Although asymptomatic bacteriuria, cystitis, and acute pyelonephritis (APN) have been categorized as urinary tract infections (UTIs), the immunopathogenesis of each disease is different. APN shows an age predilection; the majority of children (over 70-80%) with APN are under 1-2 years of age, with a male predominance. After 1-2 years of age, female predominance has been reported. This finding suggests that the immature immune state of infancy may be associated with the pathogenesis of APN. Escherichia coli is the most common etiologic agent; other uropathogens associated with UTIs originate from the host and comprise normal flora that are continuously altered by environmental factors. Therefore, uropathogens may have characteristics different from those of extraneous bacterial pathogens. Although antibiotic-resistant uropathogens, including extended-spectrum beta-lactamase-producing strains, are increasing in Korea and worldwide, treatment failure is rare in immune-competent children. The immunopathogenesis of APN remains unknown. Intact bacteria may not be the causative substances in renal cell injury; rather, smaller substances produced during bacterial replication may be responsible for renal cell injury and scarring. Moreover, substances from host cells such as proinflammatory cytokines may be involved in renal cell injury. A dimercaptosuccinic acid scan is used to detect the site of bacterial replication in the renal parenchyma, and may be influenced by the size of the focus and the stage of APN. Traditional aggressive studies used to identify vesicoureteral reflux after the first episode of APN have been modified because of rare cases of chronic kidney disease in patients with recurrent UTI.

Which Factors Related to the Renal Cortical Defects in Infants Under 3 Months of Age with Urinary Tract Infections?

PURPOSE: We used technetium-99m dimercaptosuccinic acid (DMSA) scintigraphy to identify factors predictive of renal cortical defects in infants <3 months of age with urinary tract infections (UTIs). METHODS: We retrospectively reviewed data on infants <3 months of age with culture-proven UTIs treated at a single center from March 2010 to February 2016. Blood samples were obtained for laboratory evaluation prior to commencement of antibiotic therapy. The therapeutic delay time (TDT) and therapeutic response time (TRT) were recorded. All patients were divided into two groups depending on features of their DMSA scans. We compared the demographic, clinical, and laboratory characteristics of the two groups. RESULTS: A total of 119 infants (94 males and 25 females; mean age, 56.9±21.3 days) were included. Cortical defects were evident in the DMSA scans of 47 cases (39.5%). In infants with such defects, the peak temperatures (38.9±0.57℃ vs. 38.4±0.81℃, P=0.001), the absolute neutrophil counts (8,920±4,460/mm vs. 7,290±4,090/mm, P=0.043), and the C-reactive protein (CRP) levels (6.49±4.33 mg/dL vs. 3.21±2.81 mg/dL, P=0.001) were significantly higher than those in infants without cortical defects. The TDT was also longer in those with cortical defects (P=0.037). CONCLUSION: We found that a TDT ≥8.5 hr (odds ratio [OR] 5.81), a peak temperature ≥38.3℃ (OR 6.19), and a CRP level ≥4.96 mg/dL (OR 7.26) predicted abnormal DMSA scan results in infants <3 months of age with UTIs.

Clinical Significance of Uptake Difference on DMSA Scintigraphy in Pediatric Urinary Tract Infection

PURPOSE: Disruption of normal renal development can lead to congenital anomalies of the kidney and urinary tract, including renal hypodysplasia. We aimed to clarify whether small kidney size affects clinical manifestations in children with urinary tract infection (UTI). METHODS: One hundred fifty-four patients who had their first symptomatic UTI between January 2014 and June 2015 were enrolled in this study. Differences in kidney size were estimated based on percent uptake of (99m)Tc-dimercaptosuccinic acid (DMSA) in scintigraphy. The patients who showed more than 10% difference in kidney size on DMSA scintigraphy with none or minimal cortical defects were included in group A. (group A, n=17). Laboratory, clinical, and imaging results were compared with those of the other patients (group B, n=137). RESULTS: Group A had a relatively higher incidence of vesicoureteral reflux than group B (44% vs 20%, P<0.05). The levels of plasma neutrophil gelatinase-associated lipocalin (NGAL) and serum C-reactive protein were significantly higher in group A (193 [64-337] vs 91 [59-211] ng/mL and 4.1 [0.5-11.9] vs 2.1 [0.7-5.3] ng/mL, respectively; all P<0.05). Linear regression analysis revealed that plasma NGAL level strongly correlated with the difference in renal uptake in DMSA scintigraphy in group A (R²=0.505). CONCLUSION: The difference in kidney size could influence the clinical course and severity of pediatric UTI.

Prognostic Factors of Renal Scarring on Follow-up DMSA Scan in Children with Acute Pyelonephritis

PURPOSE: Early diagnosis and treatment of urinary tract infection have been emphasized to prevent renal scarring. If untreated, acute pyelonephritis could cause renal injury, which leads to renal scarring, hypertension, proteinuria, and chronic renal failure. The purpose of this study was to assess risk factors of renal scarring after treatment of acute pyelonephritis (APN). METHODS: The medical records of 59 patients admitted at Daegu Fatima Hospital because of APN between March 2008 and April 2015 whose renal cortical defects were confirmed by using initial technetium-99m dimercaptosuccinic acid (DMSA) scans were reviewed retrospectively. We divided 59 patients into 2 groups according to the presence of renal scar and assessed risk factors of renal scar, including sex, age at diagnosis, feeding method, hydronephrosis, bacterial species, vesicoureteral reflux, and vesicoureteral reflux grade. RESULTS: Of 59 patients (41%), 24 showed renal scar on follow-up DMSA scan. No significant differences in sex, hydronephrosis, bacterial species, and fever duration were found between the renal-scarred and non-scarred groups. As for age at diagnosis, age of >12 months had 5.8 times higher incidence rate of renal scarring. Vesicoureteral reflux (VUR) affected renal scar formation. VUR grade III or IV had 14.7 times greater influence on renal scar formation than VUR grade I or II. CONCLUSION: Our data suggest that the presence of VUR and its grade and age at diagnosis are risk factors of renal scar on follow-up DMSA scan after APN.