• Childhood Kidney Diseases
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• v.7 no.1
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• pp.38-43
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• 2003

Purpose : Accurate diagnosis of acute pyelonephritis(APN) using clinical and laboratory parameters is often difficult in children. Clinical and experimental studies have demonstrated that renal scarring can be prevented or diminished by early diagnosis and aggressive treatment of acute pyelonephritis. dimercaptosuccinic acid(DMSA) renal scan has been reported to be useful in children for confirmation of the diagnosis of acute pyelonephritis. An analysis was undertaken to correlate the clinical and laboratory manifestations of APN With the results of the DMSA renal scan in different age groups. Methods : We determined the sensitivity of DMSA renal scan in febrile urinary tract infections(UTI) in two groups according to age : group I in less than 2 years; group II in older than 2 years. During the period March 2001 through September 2002, 67 children presented with febrile UTIs. All patients had DMSA renal scan done in the acute period, 55 had voiding cystourethrography(VCUG) and 66 had renal ultrasonogram(RUS) done. Results : There were no significant difference between the two groups in DMSA renal scan (P>0.05). But, in group I sensitivity of DMSA renal scan was 47%; in group II sensitivity of DMSA renal scan was 70%. The grade of reflux correlated with a positive DMSA renal scan. Vesicoureteral reflux did not correlate with age. RUS did not correlate with a positive DMSA renal scan in any age group. Abnormality of RUS did not correlate with age. Conclusion : At present, we believe that DMSA renal scan is the prevailing method in differention of the APN. In addition, it is not invasive and less costly. Even though there is no statistical difference in the sensitivity of DMSA renal scan between young and older children, we can observe that in the younger group, the sensitivity of DMSA renal scan seemed to be lower(47%).

• The Korean Journal of Nuclear Medicine Technology
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• v.25 no.1
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• pp.15-20
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• 2021

Purpose This article studies the relationship between the length of a kidney measured by two scanning methods: Kidney Computed Tomography (CT) and ^99mTc-Dimercaptosuccinic acid (DMSA) renal scan. Kidney CT provides a better anatomic assessment, while ^99mTc-DMSA renal scan is superior in the kidney function test. Materials and Methods From January to December of 2019, two hundred patients who had Kidney CT and Tc^99m-DMSA renal scan were chosen for this study. SPSS17.0 was selected for statistical analysis. Results Due to the effect of the breathing and resolution of ^99mTc-DMSA renal scan, it showed the kidney's relatively longer length than the length of Kidney CT. For the same kidney, the length comparison among different brands' Gamma cameras was negligible. The length difference within the same age group did not show a noticeable discrepancy. However, there was a length difference between the radio technologists. Kidney CT and ^99mTc-DMSA renal scan indicated a strong positive correlation between the length of the left and right kidney. Conclusion It is necessary to establish a standardized measurement method for measuring kidney length using ^99mTc-DMSA renal scan. The kidney's functional changes and length changes are indications of Kidney diseases. Especially, pediatric patients tend to use ^99mTc-DMSA renal scan for assessing the kidney's shape and the function to avoid potential radiation exposure during the Kidney CT. Therefore, it is significant to provide not only the kidney's functional information but also an anatomic analysis, including the kidney's size, length, and location through the ^99mTc-DMSA renal scan.

• Childhood Kidney Diseases
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• v.23 no.1
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• pp.36-42
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• 2019

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 ($63.2{\pm}11.3mm$ vs. $58.4{\pm}7.8mm$, P<0.001; $64.9{\pm}11.2mm$ vs. $59.9{\pm}7.9mm$, P<0.001; respectively). A significant difference was observed in both renal lengths between children with positive and negative DMSA scan results ($4.6{\pm}3.8mm$ vs. $3.3{\pm}2.6mm$, 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.

• The Korean Journal of Nuclear Medicine
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• v.23 no.2
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• pp.201-207
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• 1989

Patients with acute pyleonephritis may present with a spectrum of clinical symptoms and signs. There are few noninvasive diagnostic studies, however, to confirm or exclude this diagnosis. To evaluate the clinical utility of $^{99m}Tc-DMSA$ renal scan in diagnosis of acute pyelonephritis, we performed $^{99m}Tc-DMSA$ renal scan in 37 patients suspected with urinary tract infection. Simultaneously, kidney ultrasonography was done in 21 patients diagnosed with acute pyelonephritis, clinically. And we performed the followup scan after treatment in two to six weeks. The results were as follows: 1) $^{99m}Tc-DMSA$ renal scan disclosed single or multiple cortical defects and decreased radiouptake ratio of affected kidney in 23 patients among 25 patients diagnosed with acute pyleonephritis. 2) In the 21 patients with acute pyelonephritis, kidney ultrasonography showed abnormal finding in the 7 patients. And $^{99m}Tc-DMSA$ renal scan disclosed abnormal cortical defects in this 7 patients also. 3) Between the patients with acute pyelonephritis and those with lower urinary tract infection, asymptomatic bacteriuria or pyuria. right-to-left radiouptake ratios (R/L ratio) were significantly different (p < 0.001). 4) In two to six weeks after antibiotic therapy, we performed followup $^{99m}Tc-DMSA$ renal scan for 5 patients among 25 acute pyelonephritis patients. And we have found the improvement of cortical defects and the right-to-left radiouptake ratio. In conclusion, we thought that $^{99m}Tc-DMSA$ renal scan should be useful in diagnosis of acute pyelonephritis and follow-up examination.

• Childhood Kidney Diseases
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• v.10 no.2
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• pp.201-212
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• 2006

Purpose : Vesicoureteral reflux(VUR) is the major risk factor of urinary tract infection(UTI) in children and may result in serious complications such as renal scarring and chronic renal failure. The purpose of this study was to evaluate the relationship between VUR and renal scar formation, the usefulness and correlation of various imaging studies in reflux nephropathy, and the spontaneous resolution of VUR. Methods : We retrospectively reviewed 106 patients with VUR with no accompanying urogenital anomalies in the Department of Pediatrics, Bundang CHA Hospital during the period from Jan. 1996 to Mar. 2005. Ultrasonography and $^{99m}Tc$-dimercaptosuccinic acid(DMSA) scan were performed in the acute period of UTI. Voiding cystourethrography(VCUG) was performed 1 to 3 weeks after treatment with UTI. Follow-up DMSA scan was performed 4 to 6 months after treatment and a follow-up VCUG was performed every 12 months. Results : The mean age at detection of VUR was $13.8{\pm}22.2$ months and the male to female ratio was 2:1. The incidence of renal scarring showed a tendency of direct correlation between severity of VUR(P<0.001) and abnormal findings of renal ultrasonography(P<0.01). 63.2%(24 of 38 renal units) of renal parenchymal defects present in the first DMSA scan disappeared on follow-up DMSA scans. Follow-up DMSA scans detected renal scars in 7(14%) of 50 renal units with ultrasonographically normal kidneys. Meanwhile, ultrasonography did not show parenchymal defects in 7(36.8%) of 19 renal units where renal scarring was demonstrated on a follow-up DMSA scan. The spontaneous resolution rate of VUR was higher(75%) in cases with low grade(I to III) VUR(P<0.01). Conclusions : The presence and severity of VUR and abnormal findings of renal ultrasonography significantly correlated with renal scar formation. DMSA scan was useful in the diagnosis of renal defects. Meanwhile renal ultrasonography was an inadequate method for evaluating renal parenchymal damage. Therefore, follow-up DMSA scans should be performed to detect renal scars even in children with low-grade VUR and normal renal ultrasonography.

• The Korean Journal of Nuclear Medicine
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• v.37 no.3
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• pp.202-205
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• 2003

A 10 days old male infant with congenital megacalyces and megaureter, diagnosed by prenatal ultrasonographic screening, underwent Tc-99m DTPA renal scan for evaluation of urinary tract patency, Tc-99m DMSA scan for evaluation of renal cortical damage. He also underwent intravenous urography(IVU) and renal ultrasonography. Tc-99m DTPA renal scan demonstrates intense tracer accumulation in enlarged both renal pelvocalyses and ureters, which rapidly washout without diuretics administration. Tc-99m DMSA renal cortical scan shows no remarkable photon defect in both renal cortices and visible tracer uptake in both megaureter areas. Ultasonographic and IVU studios show enlarged both renal calyses and bullously dilated ureters, but no dilatation in renal pelvis. Follow up Tc-99m DTPA renal scan, peformed at one year later, also reveals intense tracer accumulation in enlarged both urinary tracts which rapidly washout without diuretics, and shows no significant change compare to the previous Tc-99m DTPA renal scan. Urinary tract obstruction and renal cortical damage can be easily evaluated with Tc-99m DTPA and Tc-99m DMSA scans in patiens with megacalyces and megaureter.

• Childhood Kidney Diseases
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• v.24 no.2
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• pp.98-106
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• 2020

Purpose: The aim of this study is to evaluate the clinical utility of late 6-month dimercapto-succinic acid (DMSA) renal scan in predicting vesicoureteral reflux (VUR) and long-lasting renal scars in children with first acute pyelonephritis (APN). Methods: A retrospective case study of children admitted with APN from January 2010 to July 2017 was performed. The study included patients with voiding cystourethrography (VCUG) and acute and late 6-month DMSA scan. We analyzed the clinical, laboratory and imaging findings of patients with and without late cortical defects at 6 months and those with or without VUR. Results: Among 145 children with APN, 50 (34.5%) had cortical defects on the late DMSA renal scan and 60 (41.4%) showed VUR. Thirteen of 38 (34.2%) children undergoing 18-month DMSA renal scan showed a long-lasting renal scars. Compared with children without late cortical defects, patients with late 6-month cortical defects had a higher incidence of VUR and long-lasting renal scars, and relapse of UTI (all P<0.05). In a multivariable analysis, both high-grade VUR and relapse of UTI were independently correlated with the presence of late 6-month cortical defects (P<0.05). Late cortical defects and relapse of UTI were also associated with the presence of VUR (P<0.05). Only the late 6-mo cortical defects was an independent predictor of long-lasting renal scars in children with APN (P<0.05). Conclusion: An abnormal late 6-month DMSA renal scan may be useful in identifying VUR and long-lasting renal scars in children diagnosed with APN.

• Childhood Kidney Diseases
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• v.19 no.2
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• pp.131-135
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• 2015

Purpose: The aim of this study was to establish a simple formula to predict renal length in children using a Technesium-99m dimercaptosuccinic acid (DMSA) scan data, and to compare it with the formula derived from ultrasonography, which is widely accepted. Methods: Children who underwent a DMSA scan and ultrasonography were reviewed retrospectively, and those who had anatomical urinary tract abnormalities or urinary tract infections were excluded. Results: A total of 230 children (84 males and 146 females; age, 1 month to 16 years; mean age, $16.8{\pm}27.4$ months). Mean renal length measured by DMSA scan was longer than that by ultrasonography ($6.38{\pm}1.16$ vs. $6.02{\pm}1.14cm$; P < 0.001). Renal length was correlated with age, weight, height, and body surface area on the DMSA scan and ultrasonography, and showed the strongest positive correlation with height. The following formulae were established to predict renal length: mean renal length (cm) = 5.433 ${\times}$ height (m) + 2.330 (R2, 0.833) using the DMSA scan data, and mean renal length (cm) = 5.367 ${\times}$ height (m) + 2.027 (R2, 0.853) using ultrasonography data. Conclusion: We propose a simple height-based formula to predict renal length in children using a DMSA scan data, and validate it by comparing with ultrasonography formula.

• Childhood Kidney Diseases
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• v.2 no.2
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• pp.145-151
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• 1998

Purpose : DMSA renal scan is known as a valuable method for evaluating acute pyelonephritis and renal scar in patients with febrile urinary tract infection or vesicoureteral reflux. We made this study, to determine the most effective use of DMSA renal scan. Methods : 155 children were admitted to the Pediatric Department of Yonsei University, Severance hospital with the symptom of urinary tract infection from January, 1992 to June, 1995. DMSA scan, renal ultrasound and VCUG were performed. One consisted of 29 patients with the diagnosis of acute pyelonephritis without vesicoureteral reflux and the otherconsistedofllpatientswithvesicoureteralreflux. Results : The follow-up DMSA scans at mean $0.99{\pm}0.46$ months after the initial DMSA scans were performed in the 29 children with acute pyetonephritis. 21($72.4\%$) of 29 children showed normal DMSA scans. 8 children with abnormal DMSA scans had follow-up DMSA scans at 2.5 months after the initial scans and 6 of 8 children showed normal DMSA scans. Only 12($41.4\%$) of 29 children showed abnormal renal ultrasound. The data about DMSA scans in 32 children with vesicoureteral reflux showed that there were abnormal DMSA scans in Grade $I;25.0\%$, Grade $II;44.5\%$, Grade $III;64.3\%$, Grade $IV;92.9\%$ and Grade $V;100.0\%$. There was a significant difference in that 36 renal unit ($68.0\%$) on DMSA renal scan and 26 renal units ($49.1\%$) on renal ultrasound showed abnormal finding(P<0.05). Conclusion : DMSA renal scan is more useful than renal ultrasound for the diagnosis of acute pyelonephritis. It is considered that if the initial DMSA scan is abnormal, a follow-up DMSA scan must be performed after 10weeks (8-12weeks) and the change in DMSA scan evaluated.

• Childhood Kidney Diseases
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• v.20 no.2
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• pp.74-78
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• 2016

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.