RESUMO
Objective To compare the diagnostic value of renal ultrasound scan (RUS) and 99Tcmdimercaptosuccinic acid (DMSA) renal scintigraphy in children with acute pyelonephritis (APN). Methods In all, 165 children with initial clinical diagnosis of APN, aged from 1.5 months to 11 yrs ( median 20 months), were included in the study, all of which were examined with RUS and DMSA renal scientigraphy. The diagnosis with DMSA renal scientigraphy results was taken as the standard reference to evaluate the diagnostic sensitivity and specificity of RUS. Results Of 99 out of all 330 kidneys that were found abnormal on DMSA renal scientigraphy, 31 were abnormal on RUS. Of the rest normal kidneys on DMSA scans renal scientigraphy, 4 were abnormal on RUS. Thus diagnostic sensitivity of RUS for APN was 31.3%(31/99) and specificity was 98.3% (227/231). Conclusions Although RUS provides with high diagnostic specificity for children with APN, its low sensitivity may underestimate the clinical evaluation of APN.More often than not, 99Tcm-DMSA renal scientigraphy is a clinical necesscity for the definite RUS diagnosis.
RESUMO
<p><b>OBJECTIVE</b>To evaluate the efficacy of (99m)Tc-dimercaptosuccinic acid (DMSA) scanning in predicting vesicoureteral reflux (VUR) among young children with febrile urinary tract infection (UTI) and to investigate the priority in applying either micturating cystourethrography (MCU) or DMSA.</p><p><b>METHODS</b>The medical records of children (age < or = 2 years), presenting with febrile UTI between January 2000 and December 2009, were retrospectively reviewed. All cases underwent DMSA renal scan within 1 week after diagnosis and MCU within 1 week after infection. According to the results of MCU, children were divided into groups of non-VUR, low-grade and high-grade VUR.</p><p><b>RESULTS</b>A total of 370 children (233 boys, 137 girls) were included, of whom 263 (71.1%) had abnormal DMSA results and 126 (34.1%) were identified as VUR on MCU. Among children with VUR, the number of high-grade was 103 (81.7%). The rate of abnormal results on DMSA of high-grade VUR group was significantly higher than the rates of the other two groups (P < 0.01). The sensitivity of DMSA for detecting high grade VUR was 99.0%. The negative predictive value was 99.1% and negative likelihood ratio was 0.03, respectively.</p><p><b>CONCLUSION</b>High-grade VUR remains an important risk factor of renal damage for young children with febrile UTI. The possibility to detect high-grade VUR on MCU is rather low when the result of DMSA is negative. It is recommended that DMSA be used before MCU to investigate the febrile UTI children at acute phase, because it would predict the majority of children with high-grade VUR while detecting renal lesions.</p>