Contrast-enhanced voiding US for grading of reflux in adult patients prior to antireflux ureteral implantation

PURPOSE: To prospectively assess contrast material-enhanced voiding ultrasonography (US) for grading of vesicoureteral reflux (VUR) and to compare results with those of voiding cystourethrography (VCUG) in adult patients undergoing antireflux ureteral implantation. MATERIALS AND METHODS: Thirty-seven consecutive adult patients who had undergone renal transplantation with Politano-Leadbetter (18 patients) or Lich-Gregoire (19 patients) technique were included on the basis of previous urinary tract infections (UTIs) and time elapsed after renal transplantation. Exclusion criterion was current UTI. US was performed by one of two sonologists with injection of saline and microbubble suspension and was recorded on videotape. Sonologists assigned VUR diagnosis in consensus after videotape review. VCUG was performed by one of two radiologists immediately after US. Radiologists were blinded to US findings and assigned VCUG diagnoses in consensus. Contingency table was used to compare US and VCUG. Agreement between US and VCUG was determined with kappa statistics. RESULTS: With VCUG, VUR was diagnosed in 15 patients and not diagnosed in 22 patients. US and VCUG results were in agreement in 14 patients with VUR and 21 patients without VUR. US sensitivity and specificity for detection of VUR were 93% (14 true-positive results in 15 abnormal cases) and 95% (21 true-negative results in 22 normal cases), respectively. Agreement between US and VCUG was 95% (kappa = 0.89, P <.001). In 11 of 14 patients, VUR grades were in agreement for US and VCUG. In three of 14 patients, US indicated a higher grade than did VCUG. VUR was diagnosed in seven of 18 Politano-Leadbetter cases and eight of 19 Lich-Gregoire cases. CONCLUSION: A high rate of agreement was seen between voiding US and VCUG.     

Importance of echography in the study of urinary tract infections in childhood

One hundred and twenty-one children with a clinical diagnosis of urinary tract infection (UTI) were examined with sonography (US), ivp and voiding cystourethrography (VCUG). In 84 patients neither US nor radiographic findings were found of pathological significance; in 16 out of 37 patients with pathological findings both US and ivp were negative, whereas VCUG was decisive for a correct diagnosis. VCUG demonstrated vesicoureteric reflux in 10 patients, posterior urethral valves in 1 patient, and small diverticula of the urinary bladder in 5 patients. In 17 of the remaining 21 cases, there was agreement between US and urographic findings, whereas in 4 cases US provided us with false positives, with images of apparent renal scarring. The mistake was caused by an incorrect US detection of unilateral duplication of the collecting systems. The authors conclude by stressing the importance of ivp in the evaluation of urinary tract infections in children, even in case of negative VCUG and US results, and suggest comparing US measurements of renal length to the distance between three contiguous lumbar vertebrae in order to obtain measurements comparable to body growth.     

Voiding cystourethrography: the initial radiologic study in children with urinary tract infection

The order in which children with urinary tract infection should undergo voiding cystourethrography (VCUG), excretory urography (EU), and/or renal ultrasonography (US) is not standardized. To determine a logical sequence of study, we performed VCUG and then either US or EU on 389 consecutive children with urinary tract infections. Thirty-seven percent (133/358) of the children were found to have reflux; of these, 22.5% (30/133) had an abnormal excretory urogram. No correlation was found between either the age of the child and the degree of reflux or the age of the child and the percentage of children with abnormal excretory urograms. Since normal EU or US results do not exclude significant reflux, VCUG is recommended as the preferred initial screening examination in children with urinary tract infection.     

Vesicoureteral reflux grading in contrast-enhanced voiding urosonography

INTRODUCTION AND OBJECTIVE: The sonographic diagnosis of vesicoureteral reflux (VUR) with contrast-enhanced voiding urosonography (VUS) is gradually increasing. With the introduction of VUS as part of the routine diagnostic imaging modalities for reflux significant reduction in the number of voiding cystourethrographies (VCUG) was possible. Like in VCUG grading of reflux in VUS is becoming more and more relevant. The aim of this study was to find out if there are any sonomorphologic and sonomorphometric parameters that would correlate with reflux grading in VCUG. Furthermore, a reflux grading system for VUS is proposed and the correlation of this grading system tested with the one of VCUG. PATIENTS AND METHODS: In one examination session a total of 186 children underwent both VUS and VCUG of whom 89 had VUR in at least one and the same kidney-ureter-unit (KUU) in both diagnostic imagings. The VUS was conducted with intravesical administration of ultrasound (US) contrast medium (Levovist). Ureteral and pelvicalyceal dilatations before administration of US contrast medium and during reflux were documented. Renal pelvic diameter was measured. The density of microbubbles in the renal pelves was scored on a scale of 1-3 (low to high). A grading system for reflux in VUS was set up similar to the international reflux grading system for VCUG with the addition of one more differentiation parameter, namely whether the reflux was primarily in a dilated or non-dilated urinary tract. Reflux grades in VUS were compared with those in VCUG. RESULTS: None of the sonomorphologic and sonomorphometric parameters demonstrated any clear cut finding that would simplify reflux grading in VUS. In 59/95 (62%) KUUs the reflux grades were the same in both examinations. In 10/95 (11%) and 26/95 (27%) KUUs, the reflux was graded lower or higher, respectively, in VUS than in VCUG. Fifty-seven percent were in a primarily dilated system and the remaining 43% in a non-dilated one. Seventy percent of KUUs diagnosed as having grade I reflux in VCUG, showed as grade 2 on VUS. CONCLUSIONS: A reflux grading system similar to the one used in VCUG can be applied in VUS. Adding the parameter reflux into a primarily dilated or non-dilated ureter and/or pelvicalyceal system may bring in a further dimension to the reflux grading in VUS. Most of the refluxes labelled as grade I in VCUG are actually grade II or higher.     

Contrast ultrasound of the urethra in children

The aim of this study was to report our experience with transperineal ultrasound in studying the urethra, as a complementary technique to contrast-enhanced voiding urosonography (VUS). The VUS was performed in 350 patients (244 males, 106 females) less than 4 years of age, and complemented with perineal US. Ultrasound of the kidneys and bladder was obtained before and during bladder filling and post-voiding. The urethra and the neck of the bladder were evaluated sagittally by transperineal ultrasound (5–7.5 MHz) before, during, and after voiding. Only cases of posterior urethral valves diagnosed at VUS were followed by voiding cystourethrography (VCUG), which was performed on a different day. A satisfactory evaluation of the urethra was obtained in 332 cases (94.86%): (a) normal urethra (n=328); and (b) posterior urethral valves (n=4). In the latter 4 cases there was concordance between results at VUS and VCUG. Eighteen cases (5.14%) were excluded from the study because the quality of the examination was suboptimal. Transperineal US offers an initial imaging modality for studying urethral pathology and thus may complement VUS. This paper was presented at the IPR meeting 2001, in Paris.     

Vesicoureteral reflux: can the urethra be adequately assessed by using contrast-enhanced voiding US of the bladder?

PURPOSE: To prospectively evaluate contrast material-enhanced voiding ultrasonography (US) for assessment of the urethra by using voiding cystourethrography (VCUG) as the reference standard. MATERIALS AND METHODS: This study was approved by the ethics committee on human research. Written informed consent was obtained for all patients. A total of 146 pediatric patients suspected of having vesicoureteral reflux underwent US with a galactose-based contrast agent. The bladder was instilled with contrast agent and then filled with saline. US images of the urethra were videotaped before catheterization and during voiding. VCUG was subsequently performed in all patients. In female patients, the probe (a 3.5- or 5-MHz sector array or a 7.5-MHz linear transducer) was positioned longitudinally between the labia. In male patients, the transducer was placed longitudinally on the scrotum and then displaced distally toward the penile urethra. During voiding, attention was focused on the distention of the urethral walls and on the caliber of both the posterior and anterior urethra, which were measured with calipers. Sensitivity and specificity were estimated by using a confidence interval (CI) of 95%. RESULTS: All female patients and 75 male patients showed a normal urethra at both US and VCUG. Posterior urethral valves (PUV) were diagnosed in three patients at voiding US and were confirmed with findings from VCUG. Urethral stenosis was diagnosed in two male patients at voiding US and was confirmed with findings from VCUG. Seven male patients who had undergone surgery for PUV were adequately evaluated with both modalities. Sensitivity of voiding US was 100% (CI 95%: 96.5%, 100%); specificity was 100% (CI 95%: 69.9%, 100%). CONCLUSION: Voiding US is a reliable imaging modality for studying the urethra.     

Ureterovesical jets in infants and children: duplex and color Doppler US studies

Ureteric jets were studied with conventional duplex Doppler (79 patients) and with color Doppler flow imaging (22 patients). Correlation with voiding cystourethrography (VCUG), performed ont he same day, was obtained in all patients. Thirty-six patients with normal VCUG results and normal renal and bladder ultrasound (US) studies served as the control group for 39 patients with vesicoureteric reflux (VUR) and 26 patients with urinary tract disorders other than reflux. The site of the ureteric orifice and duration, direction, and turbulence of the jets were recorded. Duration varied from 0.4 sec to 7.5 sec and depended largely on fluid intake. Duration varied in an individual patient by up to 2 sec from one jet to another. The direction of the normal jet was anteromedial and upward. Jets from refluxing ureters can appear normal. Severe renal parenchymal scarring reduced frequency and amplitude of the jets. Doppler analysis of the ureteric jet does not allow diagnosis or exclusion of VUR. Color Doppler was more sensitive in demonstrating ureteric jets than was gray-scale, real-time US and facilitated the study, but it was equally unable to help predict reflux.     

Simultaneous voiding cystourethrography and voiding urosonography

Purpose: 
To compare the diagnostic accuracy of contrast-enhanced voiding urosonography (VUS) and voiding cystourethrography (VCUG) during simultaneous performance of both examinations. Material and Methods: 
A total of 24 children, 16 girls and 8 boys, with a mean age of 3.5 years referred for reflux examination were recruited for the study. After transurethral bladder catheterization, radiographic contrast medium, followed directly by the US contrast medium, were administered. Fluoroscopic VCUG and VUS were carried out concurrently in the same patient. When 1 kidney was scanned by ultrasound, fluoroscopy was performed on the contralateral side. Results: 
In 19 of the 47 kidney-ureter-units (KUU) vesicoureteral reflux (VUR) was detected. In 16 units the reflux was detected by both VCUG and VUS. In 3 KUUs the reflux was detected only at VCUG. All 3 cases were grade 1. Taking the VCUG as the reference standard, VUS had 84% sensitivity, 100% specificity, 100% and 90% positive and negative predictive values, respectively. Conclusion: 
A dependable comparison could be achieved by performing VCUG and VUS at the same time and under the same conditions. It reconfirmed that VUS is reliable in the exclusion or verification of reflux.     

Magnetic resonance voiding cystourethrography for vesicoureteral reflux

PURPOSE: To assess the feasibility of magnetic resonance voiding cystourethrography (MRVCUG) using MR fluoroscopy for evaluation of vesicoureteral reflux (VUR), and its use as a noninvasive alternative to standard VCUG. MATERIALS AND METHODS: A total of 22 MR studies of 16 patients (five months to 41 years old) with primary VUR diagnosed by standard VCUG were evaluated. Six patients underwent MR studies and standard VCUG pre- and postoperatively. MR fluoroscopy was executed with a non-enhanced heavily T2-weighted single-shot fast spin-echo (FSE) sequence. The MR findings were correlated with those obtained by the gold standard, standard VCUG. RESULTS: Of the 44 kidney-ureter units, 20 were refluxing on MRVCUG and 21 were refluxing on standard VCUG. There were one false-positive and two false-negative units. MRVCUG was 90% sensitive with a specificity of 96% for detecting VURs that were calculated based on kidney-ureter units. Two false-negative units were found in mild cases (grade I and II). For the units of grade III, IV, and V (high-grade reflux), MRVCUG detected all of the refluxing renal collecting systems. CONCLUSION: MRVCUG can demonstrate high-grade reflux without ionizing radiation or catheterization.     

Magnetic resonance voiding cystography in the diagnosis of vesicoureteral reflux: comparative study with voiding cystourethrography

PURPOSE: To evaluate the feasibility of magnetic resonance voiding cystography (MRVC) compared with voiding cystourethrography (VCUG) for detecting and grading vesicoureteral reflux (VUR). MATERIALS AND METHODS: MRVC was performed upon 20 children referred for investigation of reflux. Either coronal T1-weighted spin-echo (SE) or gradient-echo (GE) (fast multiplanar spoiled gradient-echo (FMPSPGR) or turbo fast low-angle-shot (FLASH)) images were obtained before and after transurethral administration of gadolinium solution, and immediately after voiding. The findings of MRVC were compared with those of VCUG and technetium-99m ((99m)Tc) dimercaptosuccinic acid (DMSA) single-photon emission computed tomography (SPECT) performed within 6 months of MRVC. RESULTS: VUR was detected in 23 ureterorenal units (16 VURs by both methods, 5 VURs by VCUG, and 2 VURs by MRVC). With VCUG as the standard of reference, the sensitivity of MRVC was 76.2%; the specificity, 90.0%; the positive predictive value, 88.9%; and the negative predictive value, 78.3%. There was concordance between two methods regarding the grade of reflux in all 16 ureterorenal units with VUR detected by both methods. Of 40 kidneys, MRVC detected findings of renal damage or reflux nephropathy in 13 kidneys, and (99m)Tc DMSA renal SPECT detected findings of reflux nephropathy in 17 kidneys. CONCLUSION: Although MRVC is shown to have less sensitivity for VUR than VCUG, MRVC may represent a method of choice offering a safer nonradiation test that can additionally evaluate the kidneys for changes related to reflux nephropathy.     

Vesico-ureteral reflux: diagnosis and staging with voiding color Doppler US: preliminary experience

INTRODUCTION: The aim of this study is to assess the accuracy of a new US examination: 'voiding color Doppler US ' in the early diagnosis and staging of vesico-ureteral reflux (VUR). The contrast agent US was SH U 508A (Levovist, Schering, Berlin), which produces a chromatic accentuation of the signals picked up by the color Doppler US. Eighteen patients (10 females, eight males) were recruited for the study. In two patients a second examination was performed for follow-up after a VUR conservative therapy. All patients were taken under examination for the evaluation of possible VUR. In all patients the voiding color Doppler US was followed by voiding cystourethrography (VCUG) and the data obtained were compared. MATERIALS AND METHODS: A total of 18 patients aged between 3 months and 10 years, were recruited for the study. The results of the examination were the following: urinary tract infections, follow-up of VUR after conservative or surgical therapy, miscellaneous indications. Voiding color Doppler US was performed, followed by a VCUG. The voiding color Doppler US consists in the trans-catheter introduction of a contrast agent SHU 508 A (Levovist, Schering, Ag. Berlin) into the bladder and a subsequent test with the color Doppler US to show or exclude the presence of reflux into the ureters and/or into the pyelo-caliceal cavity of the kidneys. After the introduction of the contrast agent US the ultrasound scanning of the bladder, the ureters and the pyelo-caliceal cavity was performed to examine the reflux degree. The ultrasonographic investigations were perfomed with AU 590 asyncronus US (Esaote Biomedica, Genova) with a 3.5 MHz convex probe. RESULTS: After the trans-catheter introduction of the contrast agent US, vesico-ureteral reflux occured in 13 patients (77.2%). The reflux degree was also measured by means of ultrasound and was later confirmed by VCUG. The mean times of each examination were as follows: initial US, 10 min; catheterization, 8 min; voiding color Doppler US, 15 min; overall VCURG examination 10 min. The overall mean duration of the voiding color Doppler US examination was 33 min. The comparable mean time for VCUG, including the catheterization time, was 20 min. No reactions of intolerance to the ultrasound contrast agent occurred. DISCUSSION AND CONCLUSIONS: The voiding color Doppler US test has evidenced in all patients the presence of the contrast agent US in the bladder after the introduction. In 13 patients (77.2%) with presence of VUR, the voiding color Doppler US test has established the reflux degree confirmed by cystourethrography. The superimposability of the data obtained with voiding color Doppler US and VCUG would seem to confirm the importance of this new ultrasonographic technique in the diagnosis and staging of VUR.     

小儿前列腺囊的X线诊断

目的 探讨小儿前列腺囊的影像学特点及诊断方法。资料与方法 对16例经手术证实或经膀胱镜、尿道镜等检查证实的前列腺囊患儿资料进行回顾性分析。16例中13例经排泄性膀胱尿道造影(VCUG)检查确诊,2例经B超检查确诊,1例在尿道成形术中发现。结果 13例VUG在后尿道后方中线处均显示对比剂充盈的类圆形囊腔,大小不等,囊壁较光滑。结论 VCUG检查是诊断小儿前列腺囊的首选方法。     

Low contrast dose voiding urosonography in children with phase inversion imaging

Voiding urosonography (VUS) using a microbubble contrast agent has been introduced as an alternative technique in the diagnosis of vesicoureteral reflux (VUR). This study was undertaken to assess if phase inversion ultrasound (PIUS), a recent microbubble specific imaging technique, has advantages over fundamental in VUS and if it allows a reduction of contrast agent dose. Forty-three children with suspected VUR (aged 3 days–12 years, average of 3.9 years) with 92 kidney-ureter units (KUU) were included. Everyone obtained a baseline US scan that was followed by VUS using Levovist as the contrast agent. Constant switching between fundamental and PIUS performed the enhanced part for comparison. Every child underwent VCUG immediately afterwards. Contrast enhancement was stronger and longer lasting on PIUS than on fundamental US in all 43 cases. Reflux was detected in a total of 21 KUU, out of 92 KUU (23%). PIUS revealed VUR in 18; fundamental in 14 KUU and VCUG depicted 16 cases of reflux (p0.29). The mean volume of Levovist dose administered to the bladder was 7.4±3.4% of the bladder volume. VUS using PI mode provided considerably stronger and longer enhancement and slightly improved the detection of VUR. It allowed a reduction of contrast dose and cost by approximately 35% over current dose recommendations for fundamental US.     

Postprocedural symptoms in children who undergo imaging studies of the urinary tract: is it the contrast material or the catheter?

The frequency, nature, and duration of postprocedural symptoms in 100 children who underwent voiding cystourethrography (VCUG) after administration of 17.2% wt/vol iothalamate meglumine, 100 children who underwent radionuclide cystography (RNC) after administration of saline and technetium-99m pertechnetate, and 28 children catheterized before diuretic renal scintigraphy (DRS) were prospectively assessed with telephone follow-up. All children were aged 2 years or older; 61 were boys, 167 were girls. Postprocedural symptoms occurred in 80 children (35.1%). The frequency of postprocedural symptoms was nearly identical in the VCUG group and the two other groups. Boys (n = 33 [54%]) had symptoms significantly more often than girls (n = 47 [28%]) (P less than or equal to .0005). Dysuria was the most common symptom (n = 75 [32.9%]) and was frequently accompanied in younger children by anxiety over going to the bathroom. Symptoms disappeared within 24 hours in 32 of 80 children (40%) and lasted 4-10 days in eight children. It is concluded that most postprocedural symptoms in children who undergo VCUG, RNC, or DRS are secondary to catheterization rather than to the use of iodinated contrast material.     

儿童扩张的前列腺囊影像学诊断

目的：探讨儿童扩张的前列腺囊影像学特点。方法回顾性分析13例儿童临床诊断为扩张的前列腺囊病例,其中6例行排泄性膀胱尿道造影(VCUG)检查,5例行 MRI 检查,2例行 VCUG 及 MRI 检查。结果8例 VCUG 均在排尿时后尿道后方膀胱后下方见类圆形或长圆形囊腔影,3例囊腔可见管状影与后尿道相通,另5例囊腔影与尿道影重叠,囊腔与后尿道相通管道显示不清。7例 MRI 检查,均在膀胱后方中线区见上下走行长圆形囊状长 T1长 T2信号,穿过前列腺中心。5例囊腔可见条形高信号与后尿道高信号相通,5例发现睾丸炎、附睾炎、阴囊炎,1例发现右肾缺如。结论VCUG 和 MRI 检查是儿童扩张的前列腺囊重要检查方法,两者各有优缺点。     

Cyclic filling cystourethrography in the study of febrile urinary tract infection in children

PURPOSE: To assess the value of cyclic voiding cystourethrography (VCUG) for the detection of reflux in a large population of children with urinary tract infection. MATERIALS AND METHODS: 234 patients (67% less than 3 years of age) underwent VCUG with two fillings in 214 cases and three fillings in 139 cases. Appearance or increase in the grade of reflux compared with previous filling was expressed as "modification of the radiology report" (MRR). The amount of contrast material, the duration of fluoroscopy and the number of films were recorded. RESULTS: The rate of reflux was 18.4% at the first filling, 16% at the second filling with 9.8% MRR and 14.7% at the third filling with 10% MRR. These results were the same for children younger and older than 3 years. For children under three years, if one considered reflux grade higher than 1, the MRR was 9.6% at the second filling and 7.5% at the third while it was 5.8% and 3% for older children. On average, the use of contrast material increased 50% with a third filling, number of films was not modified and the time of fluoroscopy increased by 6 sec per filling. CONCLUSION: VCUG is recommended in all children. The detection of reflux higher than grade 1 is more frequent with multiple fillings in children under 3 years. The increase in radiation exposure and cost seems negligible.     

The role of the plain radiograph and renal tract ultrasound in the management of children with renal tract calculi

AIMS: The aim of this retrospective study was to assess the relative efficacy of plain abdominal radiographs and detailed renal tract ultrasound (US) examination in the diagnosis and follow-up of children with renal tract calculi. METHODS: The records and imaging studies of 28 paediatric patients who had presented with proven renal tract calculi over a period of 5 years were examined. RESULTS: In 23 (82%) patients, US was the first investigation. All these patients also had plain radiographs. Plain radiographs were the first investigation in five (18%) patients. All renal calculi (100%) visible on plain films were demonstrated on US. Furthermore, detailed US often provided other clinically significant findings that were not apparent on plain films. CONCLUSION: As a result of this study it is recommend that detailed US should be the investigation of choice in children with suspected renal tract calculi.     

Cyclic voiding cystourethrography: Is vesicoureteral reflux missed with standard voiding cystourethrography?

Vesicoureteral reflux (VUR) may occur intermittently and cyclic voiding cystourethrography (VCUG) can enhance the ability of the method to detect reflux. We undertook this prospective study to assess how often VUR may occur intermittently during VCUG and to evaluate the reliability of the method by performing cyclic VCUG. Two hundred seventy-five children younger than 2 years underwent two cycles of VCUG. Ninety-seven refluxing kidney-ureter units (KUU) from 68 children were identified during the two cycles. In 18 children VUR was demonstrated in the first, and in 50 children only in the second, cycle. Discrepancy between the two cycles regarding the presence and/or grade of VUR was observed in 85 KUU from 63 of 275 children (23%). In 21 of these 63 children VUR was > or = grade III. In the presence of reflux in the first cycle, discordant findings in the second cycle were found in 11 of 23 KUU (48%) or in 13 of 18 children (72.2%). In the absence of VUR in the first cycle, the second cycle disclosed reflux in 50 of 257 children (19.5%). In conclusion, intermittent VUR occurred in up to 23% of children undergoing VCUG. In more than one-third of them VUR was of major degree. Cyclic VCUG can enhance the ability of the method to detect and grade reflux.     

Cyclic voiding cystouretrography without the use of fluoroscopic monitoring

PURPOSE: To determine whether cyclic voiding cystourethrography (VCUG) examinations can be performed without using real-time fluoroscopic monitoring. MATERIALS AND METHODS: VCUG examinations were performed in 209 children (133 girls and 76 boys). In each child, it was performed in a cyclic manner (three consecutive cycles) without using fluoroscopic monitoring and one radiograph was taken in each cycle of the examination. All patients were sedated by midazolam prior to examination. The degree of vesicoureteric reflux (VUR) was graded for each of the kidney ureter units (KUU) (total 418 KUU) separately. Statistical analysis included the comparison of the presence and absence of VUR and three ordinal-matched comparisons of each cycle. RESULTS: VCUG was detected in 37.3% of the children (78/209) and 28.7% (120/418) of the KUU. The absence of or same degree of VUR in three consecutive cycles were obtained in 345 KUU and the agreement was calculated as 82.5%. The same degree and presence of reflux were found in 85 and 89 refluxing KUU, the same negative findings (absence of VUR) in 306 and 298 KUU, and discordant findings in 27 and 31 KUU (between the first and second and between first and third cycles), respectively. Therefore, the agreement was 93.5 and 92.5% between the first and second cycles (p=0.70) and between the first and the third cycles (p=0.15), respectively. CONCLUSION: Both the cyclic nature of this study and the results indicated that VCUG without real-time fluoroscopic monitoring could be used where adequate fluoroscopic examination is not possible for children in whom VUR detection is necessary and impacts treatment. However, the responsibility of pediatric radiologist always must also include the task to provide proper equipment for imaging children with suspected VUR.     

The role of DMSA renal scintigraphy in the first episode of urinary tract infection in childhood

Objective

The role of dimercaptosuccinic acid (DMSA) renal scintigraphy in the first episode of urinary tract infection (UTI) has been the subject of debate for many years. The aim of this study was to evaluate the relationship of voiding cystourethrography (VCUG), renal ultrasonography and DMSA renal scintigraphy and to detect renal parenchymal changes by performing DMSA renal scintigraphy at 6 months after the first episode of UTI.

Methods

A prospective study was conducted in 67 hospitalized children (46 boys, 21 girls). Mean age of the patients was 0.97 ± 1.57 years (0.02–7.26 years). All children received VCUG, renal ultrasonography and DMSA renal scintigraphy. DMSA renal scintigraphy was performed at 1 and 6 months after UTI.

Results

Of 67 children, 17 (25.4 %), 23 (34.3 %) and 20 (29.9 %) had vesicoureteral reflux (VUR), abnormal renal ultrasonography and abnormal DMSA renal scintigraphy, respectively. Unilateral hydronephrosis had a significant correlation with VUR at p value 0.024. In renal units, abnormal renal ultrasonography and hydronephrosis had significant correlations with VUR at p values 0.039 and 0.021, respectively. In patients and renal units, hydronephrosis had no significant correlation with abnormal DMSA renal scintigraphy at 1 month after UTI. However, abnormal renal ultrasonography and VUR had significant correlations with abnormal DMSA renal scintigraphy at p values 0.022 and <0.001 in patients and at p values 0.024 and <0.001 in renal units, respectively. Both in patients and renal units, VUR (Grade I–III) had no significant correlation with abnormal DMSA renal scintigraphy. However, severe VUR (Grade IV–V) had significant correlations with abnormal DMSA renal scintigraphy at p values <0.001 and <0.001, respectively. Seventeen patients underwent DMSA renal scintigraphy at 6 months after UTI. In addition, 15 (88.2 %) developed persistent renal scarring.

Conclusion

Abnormal renal ultrasonography and severe VUR identify renal parenchymal changes. DMSA renal scintigraphy in the first episode of UTI should be carried out in those patients. Abnormal DMSA renal scintigraphy at 1 month after UTI has a tendency to persist.