Asociación entre el reflujo vesicoureteral y la nefroesclerosis en las infecciones urinarias / Association of vesicoureteral reflux and renal scarring in urinary tract infections

Introducción. El objetivo del estudio fue investigar la relación entre reflujo vesicoureteral (RVU) y daño renal en pacientes con infección urinaria (IU) sin fiebre, primera IU febril e IU recurrente. El objetivo secundario, determinar si la proteína C-reactiva (PCR) actuaría como predictor de nefroesclerosis en las IU febriles. Población y métodos. Estudio prospectivo; pacientes pediátricos con IU sin fiebre, primera IU febril e IU recurrente. Los análisis de laboratorio de rutina incluyeron hemograma completo, urea, creatinina, análisis de orina completamente automatizado, urocultivo y PCR. Se realizó ecografía urológica luego del diagnóstico de IU, cistouretrografía miccional tras seis semanas y gammagrafía renal estática con ácido dimercaptosuccínico marcado con 99mTc tras seis meses a todos los participantes. Resultados. Participaron 47 niños con IU sin fiebre, 48 con primera IU febril y 61 con IU recurrente. Hubo una diferencia estadísticamente significativa entre los grupos respecto de RVU y nefroesclerosis (p= 0,001 y p= 0,011, respectivamente). También hubo una diferencia estadísticamente significativa respecto de nefroesclerosis entre los pacientes con y sin RVU (p= 0,001). Además, se estableció una diferencia estadísticamente significativa respecto de nefroesclerosis (p < 0,05) en los pacientes con PCR cinco veces mayor o menor que el valor de corte aceptado (5 mg/dl). Conclusión. La proporción de nefroesclerosis fue paralela a la frecuencia de RVU. Cuanto mayor era el grado de RVU, mayor era el daño renal. Se determinó una correlación positiva entre PCR elevada y nefroesclerosis, lo que señala esclerosis durante el diagnóstico de pielonefritis.

Introduction. The aim was to investigate the relationship between vesicoureteral reflux (VUR) and renal damage in non-febrile, febrile for the first time and recurrent urinary tract infection (UTI) patients. The secondary aim was to determine whether C-reactive protein (CRP) in febrile UTIs could be a predictor of renal scarring. Population and methods. This prospective study included non-febrile, febrile for the first time and recurrent pediatric UTI cases. The routine lab analyses comprised a complete blood count, urea, creatinine, fully automated urinalysis, urine culture and CRP analyses. All the participants were examined using urine ultrasonography subsequent to their UTI diagnosis, voiding cystourethrography (VCUG) after six weeks and Tc-99m dimercaptosuccinic acid (DMSA) static renal scintigraphy after six months. Results. There were included 47 children with non-febrile UTIs, 48 with first febrile UTIs and 61 with recurrent UTIs. A statistically significant difference was found among the groups in terms of VUR and renal scarring (p= 0.001 and p= 0.011, respectively). A statistically significant difference was also found in terms of renal scarring between patients with and without VUR (p= 0.001). Moreover, a statistically significant difference was also present in relation to renal scarring (p <0.05) in patients with five-fold lower or higher CRP values than the accepted cut-off value (5mg/dl). Conclusion. The ratio of renal scars detected was found to be parallel to the VUR frequency. The higher the VUR grade, the more renal damage was found. A positive correlation between elevated CRP and renal scarring was determined, indicating the presence of scarring during the diagnosis of pyelonephritis.

The role of fetal-maternal microchimerism as a natural-born healer in integrity improvement of maternal damaged kidney

ABSTRACT Purpose: To identify the fetal stem cell (FSC) response to maternal renal injury with emphasis on renal integrity improvement and Y chromosome detection in damaged maternal kidney. Materials and Methods: Eight non-green fluorescent protein (GFP) transgenic Sprague-Dawley rats were mated with GFP-positive transgenic male rats. Renal damage was induced on the right kidney at gestational day 11. The same procedure was performed in eight non-pregnant rats as control group. Three months after delivery, right ne- phrectomy was performed in order to evaluate the injured kidney. The fresh perfused kidneys were stained with anti-GFP antibody. Polymerase chain reaction (PCR) assay was also performed for the Y chromosome detection. Cell culture was performed to detect the GFP-positive cells. Technetium-99m-DMSA renal scan and single-photon emission computed tomography (SPECT) were performed after renal damage induction and 3 months later to evaluate the improvement of renal integrity. Results: The presence of FSCs was confirmed by immune histochemical staining as well as immunofluorescent imaging of the damaged part. Gradient PCR of female rat purified DNA demonstrated the presence of Y-chromosome in the damaged maternal kidney. Moreover, the culture of kidney cells showed GPF- positive cells by immuno- fluorescence microscopy. The acute renal scar was repaired and the integrity of dam- aged kidney reached to near normal levels in experimental group as shown in DMSA scan. However, no significant improvement was observed in control group. Conclusion: FSC seems to be the main mechanism in repairing of the maternal renal injury during pregnancy as indicated by Y chromosome and GFP-positive cells in the sub-cultured medium.

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.

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 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.

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.

High Spontaneous Resolution Rates of Severe Primary Vesicoureteral Reflux and Minimal Development of New Renal Scars

PURPOSE: The previous reports regarding VUR resolution were not precise due to early frequent surgical intervention. We evaluated the spontaneous resolution (SR) rate and the incidence of new renal scars in primary VUR, focusing on severe reflux. METHODS: Medical records of 334 patients with primary VUR who were on medical prophylaxis without surgery for 1 to 9 years, were retrospectively reviewed. Medical prophylaxis was initiated with low-dose antibiotic prophylaxis or probiotics. Radioisotope cystourethrography was performed every 1 to 3 years until SR of reflux. New renal scar was evaluated with follow-up 99mTc DMSA renal scan. RESULTS: The SR rates decreased as VUR grades were getting higher (P=0.00). The overall and annual SR were 58.4% and 14.9%/yr in grade IV reflux and 37.5% and 9.3%/yr in grade V reflux. The median times of SR were 38 months in grade IV reflux and 66 months in grade V reflux. The probable SR rates in grade IV and V reflux were 7.8% and 8.9% in the 1st year, 46.0% and 30.8% in the 3rd year and 74.4% and 64.4% in the 5th year. The incidences of new renal scars between low to moderate reflux and severe reflux showed no significant difference (P=0.32). CONCLUSION: The SR rates of severe primary VUR were higher than previously reported and most new renal scars were focal and mild.

Prediction of Cortical Defect Using C-Reactive Protein and Urine Sodium to Potassium Ratio in Infants with Febrile Urinary Tract Infection

PURPOSE: We investigated whether C-reactive protein (CRP) levels, urine protein-creatinine ratio (uProt/Cr), and urine electrolytes can be useful for discriminating acute pyelonephritis (APN) from other febrile illnesses or the presence of a cortical defect on 99mTc dimercaptosuccinic acid (DMSA) scanning (true APN) from its absence in infants with febrile urinary tract infection (UTI). MATERIALS AND METHODS: We examined 150 infants experiencing their first febrile UTI and 100 controls with other febrile illnesses consecutively admitted to our hospital from January 2010 to December 2012. Blood (CRP, electrolytes, Cr) and urine tests [uProt/Cr, electrolytes, and sodium-potassium ratio (uNa/K)] were performed upon admission. All infants with UTI underwent DMSA scans during admission. All data were compared between infants with UTI and controls and between infants with or without a cortical defect on DMSA scans. Using multiple logistic regression analysis, the ability of the parameters to predict true APN was analyzed. RESULTS: CRP levels and uProt/Cr were significantly higher in infants with true APN than in controls. uNa levels and uNa/K were significantly lower in infants with true APN than in controls. CRP levels and uNa/K were relevant factors for predicting true APN. The method using CRP levels, u-Prot/Cr, u-Na levels, and uNa/K had a sensitivity of 94%, specificity of 65%, positive predictive value of 60%, and negative predictive value of 95% for predicting true APN. CONCLUSION: We conclude that these parameters are useful for discriminating APN from other febrile illnesses or discriminating true APN in infants with febrile UTI.

Ureteral visualization in a technetium-99m dimercaptosuccinic acid scan

Technetium-99m dimercaptosuccinic acid (99mTc-DMSA) scan is performed when there is a need to visualize the renal cortex and not the ureters or the bladder as the latter two are not effectively imaged. Less than twenty cases of tracer accumulation in a dilated ureter during a 99mTc-DMSA scan have been reported worldwide. There is no published case of ureter visualization in a 99mTc-DMSA scan done in the Philippines. In the case at hand, visualization of the ureters prompted further investigation. The present study pointed to a consideration of obstructive hydroureter, which was eventually supported by VCUG findings. Ureteral visualization in a 99mTc-DMSA scan should therefore prompt the inclusion of megaureter in the differential diagnosis.

Clinical Guideline for Childhood Urinary Tract Infection (Second Revision)

To revise the clinical guideline for childhood urinary tract infections (UTIs) of the Korean Society of Pediatric Nephrology (2007), the recently updated guidelines and new data were reviewed. The major revisions are as follows. In diagnosis, the criterion for a positive culture of the catheterized or suprapubic aspirated urine is reduced to 50,000 colony forming uits (CFUs)/mL from 100,000 CFU/mL. Diagnosis is more confirmatory if the urinalysis is abnormal. In treating febrile UTI and pyelonephritis, oral antibiotics is considered to be as effective as parenteral antibiotics. In urologic imaging studies, the traditional aggressive approach to find primary vesicoureteral reflux (VUR) and renal scar is shifted to the targeted restrictive approach. A voiding cystourethrography is not routinely recommended and is indicated only in atypical or complex clinical conditions, abnormal ultrasonography and recurrent UTIs. 99mTc-DMSA renal scan is valuable in diagnosing pyelonephritis in children with negative culture or normal RBUS. Although it is not routinely recommended, normal scan can safely avoid VCUG. In prevention, a more natural approach is preferred. Antimicrobial prophylaxis is not supported any more even in children with VUR. Topical steroid (2-4 weeks) to non-retractile physiologic phimosis or labial adhesion is a reasonable first-line treatment. Urogenital hygiene is important and must be adequately performed. Breast milk, probiotics and cranberries are dietary factors to prevent UTIs. Voiding dysfunction and constipation should be properly treated and prevented by initiating toilet training at an appropriate age (18-24 months). The follow-up urine test on subsequent unexplained febrile illness is strongly recommended. Changes of this revision is not exclusive and appropriate variation still may be accepted.

Are Clinical, Laboratory, and Imaging Markers Suitable Predictors of Vesicoureteral Reflux in Children With Their First Febrile Urinary Tract Infection?

PURPOSE: This study was conducted to determine the predictive value of clinical, laboratory, and imaging variables for the diagnosis of vesicoureteral reflux in children with their first febrile urinary tract infection. MATERIALS AND METHODS: One hundred fifty-three children with their first febrile urinary tract infection were divided into two groups according to the results of voiding cystourethrography: 60 children with vesicoureteral reflux and 93 children without. The sensitivity, specificity, positive and negative predictive value, likelihood ratio (positive and negative), and accuracy of the clinical, laboratory, and imaging variables for the diagnosis of vesicoureteral reflux were determined. RESULTS: Of the 153 children with febrile urinary tract infection, 60 patients (39.2%) had vesicoureteral reflux. There were significant differences between the two groups regarding fever>38degrees C, suprapubic pain, C-reactive protein quantitative level, number of red blood cells in the urine, and results of renal ultrasound and dimercaptosuccinic acid renal scanning (p38.2degrees C and dimercaptosuccinic acid renal scanning and vesicoureteral reflux. Also, there were significant positive correlations between the erythrocyte sedimentation rate, positive urinary nitrite test, hyaline cast, and renal ultrasound and high-grade vesicoureteral reflux. CONCLUSIONS: This study revealed fever>38.2degrees C and dimercaptosuccinic acid renal scanning as the best predictive markers for vesicoureteral reflux in children with their first febrile urinary tract infection. In addition, erythrocyte sedimentation rate, positive urinary nitrite test, hyaline cast, and renal ultrasound are the best predictive markers for high-grade vesicoureteral reflux.

Differences in the Clinical Characteristics of Children with Urinary Tract Infections Based on the Results of 99mTc-Dimercaptosuccinic Acid Renal Scanning

PURPOSE: The 99mTc-Dimercaptosuccinic acid (DMSA) renal scan is used primarily for the diagnosis of renal scarring and acute pyelonephritis in children with urinary tract infections (UTI). This study aimed to evaluate clinical differences based on the positive or negative results of DMSA scans and kidney ultrasonography (US) in pediatric UTI. METHODS: We retrospectively reviewed 142 pediatric patients with UTI who were admitted to Myongji Hospital from January 2004 to December 2012. We performed a comparative analysis of clinical parameters such as age, sex, white blood cell (WBC) count, neutrophil count, blood urea nitrogen (BUN) level, creatinine (Cr) level, C-reactive protein (CRP) level, and durations of hospitalization and fever, grouped by the results of the DMSA scans and kidney US. RESULTS: The mean age of the patients was 33.8+/-48.3 months, and 78 (55%) were male. Fifty-two patients had abnormal DMSA findings, and 71 patients had abormal kidney US findings (test positive groups). In the DMSA scan positive group, there were significant differences in age, WBC counts, neutrophil counts, CRP level, BUN level, Cr level, hospitalization duration, number of abnormal findings on kidney US, and incidence of vesicoureteral reflux (VUR) compared with the scan negative group. The kidney US positive group had significant differences in age, neutrophil count, CRP level, BUN level, Cr level, hospitalization duration, number of abnormal findings on the DMSA scans, and more frequent VUR compared with the US negative group. CONCLUSION: Our data suggest that there were no major differences in clinical parameters based on the results of the DMSA scans compared with kidney US in pediatric UTI. However, as kidney US and DMSA scan were performed to predict VUR, the sensitivity and negative predictive value was increased.

Preparation and evaluation of [99m]Tc-DMSA lyophilized kit for renal imaging

Dimercaptosuccinic acid [DMSA] has been evaluated and used with technetium 99m [[99m]Tc] in imaging of kidneys. DMSA lyophilized kits were prepared and radiolabelled with [99m]Tc. Paper and thin-layer chromatography have been employed using various eluent systems for the radiochemical analysis, percentage labeling and binding capacity of [99m]Tc-DMSA. Female albino rabbits were used for this study. Biological data obtained after intravenous injection of radiolabelled DMSA to female albino rabbits revealed 32.42% uptake and long retention time in the kidneys. On the basis of animal biodistribution data, it is suggested that DMSA when labeled with [99m]Tc is useful complex for renal imaging and can be successfully applied as a diagnostic tool in nuclear medicine. Clinical biodistribution and radiation dosimetry studies are planned in future

Abnormal Dimercaptosuccinic Acid Scan May Be Related to Persistence of Vesicoureteral Reflux in Children with Febrile Urinary Tract Infection

PURPOSE: This study assessed whether 99mtechnetium dimercaptosuccinic acid (DMSA) scintigraphy used for the assessment of renal sequelae after febrile urinary tract infection (UTI) has any prognostic value for outcome measurement of vesicoureteral reflux (VUR) by retrospectively evaluating the correlation between abnormal DMSA scintigraphy results and persistence of VUR in children with febrile UTI. MATERIALS AND METHODS: The medical records of 142 children (57 boys, 85 girls) admitted with febrile UTI from January 2004 to December 2006 and who were followed up for more than 1 year were retrospectively reviewed. At the initial and follow-up visits, renal ultrasound and DMSA scans were performed within 7 days from the diagnosis and voiding cystourethrography (VCUG) was performed within 1 month in all case and follow-up evaluations. RESULTS: The children's mean age was 4.8+/-3.6 years (range, 0.3 to 14 years). The mean follow-up was 28.2+/-4.8 months. At the initial examination, VUR was more often associated with an abnormal DMSA scan result (83.3%) than with a normal DMSA scan result (16.7%, p=0.02). The frequency of VUR with an abnormal DMSA scan during acute UTI was significantly higher than the frequency of VUR with a normal DMSA scan (38.8% vs, 25.8%, respectively, p=0.004). Also, high-grade VUR was associated with an abnormal DMSA scan result (32.5%) more often than with a normal DMSA scan result (0%, p=0.01). Children with an abnormal DMSA scan had a lower resolution rate of VUR (17.5%) than did children with a normal DMSA scan (75.0%) at the follow-up VCUG (p=0.02). CONCLUSIONS: An abnormal result on a DMSA scan during febrile UTI is associated with high-grade and persistent VUR. DMSA scans performed during febrile UTI are useful in reflux resolution in childhood.

Usefulness of Spot Urine beta2-microglobulin in Pediatric Acute Pyelonephritis

OBJECTIVE: It is difficult to make a distinction between acute pyelonephritis and lower urinary tract infection due to nonspecific clinical symptoms and laboratory findings. We measured the spot urine beta2-microglobulin in children with urinary tract infection (UTI) to distinguish between acute pyelonephritis and lower UTI. We compared the accuracy of urine beta2-microglobulin measurement with other inflammatory markers. METHODS: We studied 83 children (mean, 86+/-44.9 months) who suspected of having UTI. Leukocyte counts, erythrocyte sedimentation rates (ESR) and C-reactive protein (CRP), beta2-microglobulin were measured. Renal parenchymal involvement was evaluated by 99mTc dimercaptosuccinic acid scintigraphy in the first 7 days after admission. beta2-microglobulin was measured by radioimmunoassay. RESULTS: Urine beta2-microglobulin values were correlated with the presence of renal defects in children with UTI (n=22) (0.98+/-0.24 microg/mL, P<0.05). Using a cutoff of 0.4 microg/mL for spot urine beta2-microglobulin and 20 mm/hr for ESR, 2.6 mg/L for CRP, sensitivity and specificity between UTI with and without renal involvement were 78.7% and 90.1% for spot urine beta2-microglobulin, 77.2% and 90.1% for spot urine beta2-microglobulin/creatinine (Cr), 77.2%, 68.8% for ESR, 86.3%, 68.8% for CRP, respectively. Positive and negative predictive values were 72.7%, 90.1% for spot urine beta2-microglobulin, 73.9% and 91.6% for spot urine beta2-microglobulin/Cr, and 57.5%, 94% for CRP, respectively. CONCLUSION: In febrile UTI, spot urine beta2-microglobulin and beta2-microglobulin/Cr values were more specific than CRP, ESR, and leukocyte count for determine the renal defects.

Prediction of vesicoureteral reflux in children with first urinary tract infection by dimercaptosuccinic acid and ultrasonography

Urinary tract infection [UTI] is one of the most common causes of febrile pediatric diseases. Also, vesicoureteral reflux [VUR] is a significant risk factor for UTI. Voiding cystourethrography [VCUG] is the method of choice for evaluation of VUR. This study was done to predict VUR by DMSA scan [technetium 99 m-labeled dimercaptosuccinic acid] and ultrasonography [US]. In a prospective study, all children with first time acute pyelonephritis were selected and evaluated by DMSA scan and US. Then VCUG was done with negative urine culture. All children with final diagnosis of obstructive congenital anomaly were excluded. The sensitivity, specifity, positive predictive values, negative predictive values, Confidence Interval of DMSA scan and US were calculated for prediction or exclusion of VUR. Among 100 children with UTI diagnosis, VUR was detected in 39 children and 63 [31.5%] kidneys. DMSA scan was abnormal in 103 [51.5%] units, 45 units had VUR [PPV=44%], 79 units with normal DMSA scan had no VUR [NPV=81%]. Of kidney units that were abnormal by DMSA or US, 51 units had VUR. PPV and NPV were 44% and 56%, respectively. DMSA scan alone or with US cannot predict VUR [especially low grade VUR]. But according to NPV, it seems that absence of VUR can be predicted. So, more studies are needed to determine the usefulness of DMSA scan and US instead of VCUG for detection of VUR

Discordant findings on dimercaptosuccinic acid scintigraphy in children with multi-detector row computed tomography-proven acute pyelonephritis / 소아과

PURPOSE: The diagnosis of acute pyelonephritis (APN) is often difficult, as its clinical and biological manifestations are non-specific in children. If not treated quickly and adequately, however, APN may cause irreversible renal damage, possibly leading to hypertension and chronic renal failure. We were suspecting the diagnostic value of 99mTc-dimercaptosuccinic acid (DMSA) scan by experiences and so compared the results of DMSA scan to those of multi-detector row computed tomography (MDCT). METHODS: We retrospectively selected and analyzed 81 patients who were diagnosed as APN by MDCT during evaluation of their acute abdomen in emergency room and then received DMSA scan also for the diagnostic work-up of APN after admission. We evaluated the results of imaging studies and compared the diagnostic value of each method by age groups, or =2 years (n=36). RESULTS: Among total 81 patients with MDCT-proven APN. DMSA scan was diagnostic only in 55 children (68%), while the remaining 26 children (32%) showed false negative normal findings. These 26 patients were predominantly male with average age of 21 months and most of them, 19 (73.1%) were <2 years of age. CONCLUSION: DMSA scan has obvious limitation compared to MDCT in depicting acute inflammatory lesions of kidney in children with APN, especially in early childhood less than 2 years of age. MDCT showed hidden lesions of APN, those were undetectable through DMSA scan in children.

Renal power doppler ultrasonographic evaluation of children with acute pyelonephritis

Urinary tract infections are common in children. The available gold standard method for diagnosis, Tc-99m dimercaptosuccinic acid scan is expensive and exposes patients to considerable amount of radiation. This study was performed to compare and assess the efficacy of Power Doppler Ultrasound versus Tc-99m DMSA scan for diagnosis of acute pyelonephritis. A quasi experimental study was conducted on 34 children with mean age of 2.8?2.7 years who were hospitalized with their first episode of febrile urinary tract infection. All children were evaluated in the first 3 days of admission by Doppler Ultrasound and Tc-99m DMSA scan. Patients with congenital structural anomalies were excluded. Each kidney was divided into three zones. The comparison between efficacy of Doppler Ultrasound and DMSA scan was carried out based on number of patients and on classified renal units. Based on the number of patients enrolled; the sensitivity, specificity, positive and negative predictive values and accuracy of Doppler Ultrasound were 89%, 53%, 70%, 80% and 74%, respectively but based on the renal units, it was 66%, 81%, 46%, 91% and 79%, respectively. Although Doppler Ultrasound has the potential for identifying acute pyelonephritis in children, but it is still soon to replace DMSA scan