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.

The Decision of Voiding Cystourethrography in Children with Urinary Tract Infection

PURPOSE: We attempted to compare the independent factors such as age, sex, C-reactive protein(CRP), and white blood cell count(WBC) in children with radiologic studies and assess the necessity of performing voiding cystourethrography(VCUG). METHOD: 98 children who have been diagnosed their first time febrile urinary tract infection from Janurary 2002 to Januray 2005 were enrolled. In all patient, the duration of fever which occurred before and after treatment was recorded, and CRP, WBC, (99m)Tc-2,3-dimercaptosuccinic acid((99m)Tc-DMSA) renal scans, renal ultrasound and VCUG were analyzed. RESULTS: Of the 98 children diagnosed with urinary tract infection(UTI), 52 were male and 46 were female. 18 had abnormalities in VCUG, 17 had abnormalities in kidney ultrasound, and 20 had partial defects or diffuse uptake decrease in (99m)Tc-DMSA renal scans. There were no significant relationship between incidence of radiologic abnormalities and age. The risk of renal scar was significantly higher in children who had a longer febrile period before treatment than in those with shorter period. Both CRP and WBC were significantly elevated in children with the radiological abnormalities. A positive of (99m)Tc-DMSA renal scans and renal ultrasound were highly associated with vesicoureteral reflux(VUR). CONCLUSION: If there are abnormalities in the kidney ultrasound and (99m)Tc-DMSA renal scan of a child with initial UTI, a VCUG is recommended. Even in cases without abnormal findings in (99m)Tc-DMSA renal scan and renal ultrasound, clinical data such as CRP and WBC should be assessed, and VCUG should be performed for the undetected VUR.

Voiding cystourethrography in children with an initial episode of febrile urinary tract infection / 소아과

PURPOSE: Because voiding cystourethrography(VCUG) is an invasive method, we studied whether VCUG could be postponed through evaluation of alternative non-invasive tests including renal ultrasonography and (99m)Tc-DMSA renal scan. METHODS: We reviewed the medical records of 175 patients initially diagnosed with febrile urinary tract infection during the one year period of 1999, and compared 3-tests:renal ultrasongraphy, (99m)Tc-DMSA renal scan, and VCUG. RESULTS: Renal ultrasonography didn't contribute to the prognostication of pyelonephritis(photopenic areas) or vesicoureteral reflux(VUR). Presentation of photopenic areas in (99m)Tc-DMSA renal scan was related to VUR. If both findings of renal ultrasonography and (99m)Tc-DMSA renal scans were normal, this condition was closely related to normal results in VCUG. And if both examinations were abnormal, the condition was closely related to VUR. But this state could not always guarantee the normal result from VCUG because of low sensitivity in finding VUR. CONCLUSION: In cases in which acute phyelonephritis is demonstrated by (99m)Tc-DMSA renal scan, VCUG is required. In addition to this, if the conditions of hydronephrosis, vesicoureteral dilatation, increases of renal volume, and changes of echogenesity are shown by renal ultrasonography, VCUG should be performed. If a patient has difficulty undergoing VCUG, temporary postponement of VCUG can be taken into consideration, but only in cases where both examinations of renal ultrasonography and (99m)Tc-DMSA renal scan are normal. Nevertheless, close observation is be advised even in this case.

The Occurrence of Renal Scarring in Children with Unilateral Vesicoureteral Reflux / 소아과

PURPOSE: We evaluated the occurrence of renal scarring in children with unilateral vesicoureteral reflux (VUR), and the relationships between renal scar formation and risk factors such as VUR, duration of fever, acute-phase reactant, age, and sex. METHODS: We retrospectively analyzed the data of 35 children newly diagnosed with unilateral vesicoureteral reflux after urinary tract infection (UTI) in Wallace Memorial Baptist Hospital between January 1996 and December 2004. Ultrasonography, Erythrocyte sedimentation rate (ESR), and C- reactive protein (CRP) were performed initially. Voiding cystourethrography (VCUG) was performed 1 to 3 weeks after treatment with UTI. (99m) Tc-dimercaptosuccinic acid (DMSA) scan was performed 4 to 6 months after treatment. RESULTS: Scintigraphic renal damage was present in 29 percent of the refluxing and in 3 percent of the nonrefluxing kidneys (P< 0.05). The severity of VUR was significantly correlated with renal scar formation (P< 0.05). The duration of fever before treatmen (5.0+/-1.3 vs 2.6+/-1.3) and prolonged fever of over 5 days were significantly different between renal scar group and non-renal scar group (P< 0.05). ESR (56.3+/-23.8 vs 27.9+/-18.1 mm/hr, P< 0.05) and CRP (12.8+/-7.3 vs 3.9+/-3.8 mg/dL, P< 0.05) at the diagnosis of UTI in the renal scar group were higher, compared to those of the non-renal scar group. There were no significant differences in age and sex between the two groups. CONCLUSION: The presence and grade of VUR, the duration of fever before treatment, prolonged fever over 5 days, ESR, and CRP were risk factors for renal scarring, irrespective of age and sex. Diagnosis and management of VUR, in children with UTI, is important to prevent renal scars.

A Case of Acute Poststreptococcal Glomerulonephritis Accompanied with Acute Pyelonephritis

Acute poststreptococcal glomerulonephritis(APSGN) is the most common form of postinfectious glomerulonephritis, and acute pyelonephritis(APN) is the most severe form of urinary tract infection in childhood. However, the concurrence of two diseases is uncommon in the literature. We describe a case of APSGN accompanied with APN in a 5-year-old female who presented with fever, left flank pain, headache and facial edema. Urinalysis showed pyuria, microscopic hematuria, and mild proteinuira. Serial urine cultures grew Escherichia coli. (99m)Tc-DMSA renal scan revealed a cortical defect in the upper pole of left kidney. She had a history of preceding pharyngitis, in addition, showed high blood pressure, high anti-streptolysin O titer, and low serum complement levels. The patient improved completely with supportive treatment, including antibiotic and antihypertensive therapy. These findings suggested that APSGN and APN could be manifested simultaneously or be superimposed on each other.

Sensitivity of Dimercaptosuccinic Acid(DMSA) Renal Scan in Children with Acute Pyelonephritis

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 Correlation between Relative Renal Uptake of (99m)Tc-DMSA Renal Scan and Glomerular Filtration Rate in Patients with Reduced Renal Function / 대한신장학회잡지

BACKGROUND: Glomerular filtration rate(GFR) is an important parameter for the evaluation and monitoring of renal function. The aim of this study was to investigate the correlation between the relative 1 hour uptake of (99m)Tc-DMSA renal scan(DMSA- %uptake, TRUR) and GFR which was estimated by (99m)Tc-DTPA, serum creatinine and 24 hour-urinary creatinine excretion. METHODS: Between January 1998 and March 2001, 65 patients had undergone (99m)Tc-DMSA renal scan, (99m)Tc-DTPA renal scan, serum creatinine and 24 hour-urinary creatinine excretion. Of them, 42 patients had moderately or severely reduced renal function(DTPA-GFR 0.05). In group B, TRUR (mean+/-S.D. 16.3+/-7.4%) was significantly correlated with DTPA-GFR(r=0.731, p < 0.01). In both group, serum creatinine, Ccr and C and G Ccr were significantly correlated with TRUR. CONCLUSION: Although the relative 1 hour uptake of the (99m)Tc-DMSA renal scan, as a method of renal cortical image could not estimate the true GFR, it showed a good correlation with GFR in patients with moderately reduced renal function. (99m)Tc-DMSA renal scan seems to be helpful to evaluate the renal function in patients with moderately reduced renal function.

Risk Factors of Renal Scar After Acute Pyelonephritis in Children

PURPOSE: In this study we re-evaluated the known risk factors of pyelonephritic scarring in children. METHODS: A prospective study was performed on 36 acute pyelonephritis(APN) patients who were diagnosed as first acute pyelonephritis on 99mTc-DMSA scan between September 1998 and March 2000 in Masan Samsung Hospital. According to the prescence of remnant lesions on the 99mTc-DMSA scan performed 6 months after the first 99mTc-DMSA scan, the patients were divided into scar(Group A, N=15) and non-scar groups(Group B, N=21). We compared known risk factors of renal scarring between the two groups. RESULTS: There were no differences in age, sex, cultured organisms and CRP level between the two groups. Most of the initial 99mTc-DMSA scan results were not different but bilateral multiple lesions were much more common in group A(40.0% of Group A patients) compared with group B (9.5% of Group B patients). Moderate to high grade vesicoureteral reflux was also much more commonly observed in group A(46.6% of Group A patients) compared with group B(4.8% of Group B patients). CONCLUSION: Bilateral multiple lesion on initial 99mTc-DMSA scan and moderate to high grade vesicoureteral reflux at diagnosis of acute pyelonephritis may be risk factors associated with renal scarring after acute pyelonephritis in children.

Diagnostic Value of 99mTc-DMSA Renal Scan for Early Diagnosis of Acute Pyelonephritis in Children with Febrile Urinary Tract Infection

PURPOSE: For prevention of renal scar, early diagnosis and treatement of acute pyelonephritis are important in children with febrile urinary tract infection. But it has been difficult to differentiate acute pyelonephritis from lower urinary tract infection. We have performed this study to evaluate the diagnostic value of 99mTc-DMSA renal scan and to clarify the relationship among acute pyelonephritis, vesico-ureteral reflux and renal scar. METHODS: We have studied 100 patients with febrile urinary tract infection, from September, 1993 to June, 1995 at the Pediatric department of Ewha Womans University, Mok-dong hospital. Acute phase reactants, causative organism, renal ultrasound, 99mTc- DMSA renal scan on the acute stage, voiding cystouretherogram after 1-2 weeks of treatement, and follow-up 99mTc-DMSA renal scan were evaluated. RESULTS: Ther results are as follows; 1) 57 patients (57%) had defect on 99mTc-DMSA renal scan and diagnosed as acute pyelonephritis. 2) Acute phase reactants, renal ultrasound had low accuracy. 3) VUR was found in 31 (56.1%) of 57 patients with defect which was significantly higher than the 4 (9.3%) of 43 patients without defect on 99mTc-DMSA renal scan. 4) On the follow up 99mTc-DMSA renal scan, 34.8% of defects recorvered, and 65.2% of defects developed renal scar. CONCLUSIONS: 99mTc-DMSA renal scan is a valuable method for early diagnosis of acute pyelonephritis in children with febrile urinary tract infection. It would contribute to evaluate the relationship between acute pyelonephritis, vesico-ureteral reflux and renal scar.

Diagnostic Significance of DMSA Renal Scan and C-Reactive Protein in Urinary Tract Infection of Childhood

PURPOSE: Renal scar or reflux nephropathy, known as a major cause of end-stage renal failure and hypertension in children and young adults, is frequently detected in pediatric urinary tract infection(UTI) patients at their first infections. So early and accurate diagnosis, and follow up of renal scar are very important. We performed this study to recognize the importance of radiologic examinations for detection of renal scar and vesicoureteral reflux(VUR) in pediatric UTI patients at their first attacks, and to compare the accuracy and usefulness of DMSA renal scan with renal ultrasonography and IVP in early detection and follow up of renal scar. We also wanted to find the association of renal scar with VUR detected by VCUG, and increased C-reactive protein(CRP) level. METHODS: We studied on 41 pediatric UTI patients without past medical history of UTI, who were admitted to the Department of Pediatics, Kangbuk Samsung Hospital from May 1993 to August 1995. On admission a blood sample was taken for the determination of CRP. Renal ultrasonography and DMSA renal scan were performed within five days after admission. Eight weeks later, with repeated studies of renal ultrasonography and DMSA renal scan, IVP and VCUG were also performed for all patients. RESULTS: 1) The incidence of UTI was most prevalent in infancy grou(56%). The ratio of male to female patients was 4.8:1 under the age of one year, and 1:2 over the age of one year. 2) At admission, 21 of 41 patients(51%) showed renal scars in the DMSA renal scans. At follow up of DMSA renal scans, 8 weaks later, 7 of 21 initially abnormal cases(33%) became normal while 14 cases(67%) continued to show renal scars. Twenty initially normal cases continued to show normal DMSA renal scans at follow up. 3) Renal ultrasonography showed 10 abnormal cases among 41 cases(24%) at admission, and 7 abnormal cases(17%) at follow up. IVP showed 13 abnormal cases among 41 cases(32%). 4) For detection of renal scar, sensitivity and specificity of DMSA renal scan were 95% and 100%, sensitivity and specificity of renal ultrasonography were 45% and 90%, and sensitivity and specificity of IVP were 59% and 100% retrospectively. 5) VCUG showed reflux in 13 patients among 41 patients(32%). Among 20 patients with normal DMSA renal scan, only two patients(10%) showed VUR in VCUG, and they were classified as grade I and II VUR by International Reflux Study Committee classifications. Among 21 patients with abnormal by DMSA renal scan, 11 patients(52%) showed VUR in VCUG, of whom 9 patients were classified as severe reflux above grade III. 6) The mean CRP level in the patients with normal DMSA renal scan was 9.6mg/L, significantly lower than mean CRP level of patients with abnormal DMSA renal scan which was 60.57mg/L(p<0.01). CONCLUSIONS: For early detection of renal scars and reflux nephropathy, appropriate radiologic investigations including DMSA renal scan and VCUG should be done to all pediatric UTI patients at their first attacks. DMSA renal scan seemed to be better radiologic method than renal ultrasonography and IVP in early detection of renal scar and have association with VUR. We also found that blood CRP level is easy and useful test for early suspection of upper UTI.

Obstruction of the Ureteropelvic Junction in Children: Functional Evaluation of the Obstructed Kidney Postoperatively Using the 99mTc-DMSA Renal Scan / 대한비뇨기과학회지

Ten children were selected out of 21 cases diagnosed as ureteropelvic junction obstruction between March, 1989 and March, 1992. The children were evaluated quantitatively using the renal cortical labeling agent, 99m technetium dimercaptosuccinic acid (Tc-DMSA), before and following pyeloplasty. The preoperative residual renal function and the extent of functional recovery were investigated. The children ranged from 15 months to 13 years old (average 6.8 years) and consisted of 8 boys and 2 girls. The obstruction was on the left in 7 cases and the right in 3. Symptoms on admission included pain in 5 cases, abdominal mass in 3 cases, and fever and chill in 2. The subjects divided into two groups. The first group consisted of children who did not have complications or other coexisting diseases, while the second consisted of who had pyonephrosis or vesicoureteral reflux. All patients underwent dismembered pyeloplasty and the results were satisfactory in all. 1. The preoperative differential renal function by Tc-DMSA renal scintigraphy ranged from 0.5% to 46.0% (mean 19.1%) and increased to 3.5% to 46.9% (mean 28.8%) postoperatively. 2. In five of the seven cases with uncomplicated ureteropelvic junction obstruction, differential renal function increased more than 1096 following pyeloplasty. In the two other cases which showed preserved renal function of up to 4096 preoperatively, noticeable changes not observed. 3. In the three cases with complicated ureteropelvic junction obstruction, (two cases associated with pyonephrosis and one case with vesicoureteral reflux) only slight increased differential renal function. In conclusion, we suggest that severely obstructed kidneys in infants and children spare nephrectomy and encourage pyeloplasty, even in cases of non-visualization on excretory urography in hopes of improving relative renal function.