The efficacy of ultrasound and dimercaptosuccinic acid scan in predicting vesicoureteral reflux in children below the age of 2 years with their first febrile urinary tract infection

We evaluated the efficacy of dimercaptosuccinic acid (DMSA) scan and ultrasound (US) in comparison with voiding cystourethrography (VCUG) in predicting vesicoureteral reflux (VUR) in children below the age of 2 years. Medical records and radiologic studies of children (<2 years) suffering their first febrile urinary tract infection (UTI) between January 2001 and May 2007 were retrospectively reviewed. We evaluated the sensitivity, specificity, and positive and negative predictive values of US and DMSA scans in diagnosing VUR. Among 220 children with their first febrile UTI, VUR was detected in 67 (30.4%). The detection rate of VUR by US was 41.7% and 86% in the low (I, II) and high grade (III∼IV) groups, respectively. Detection rate of VUR by DMSA scan was 37.5% and 88.4% in the low and high grade groups, respectively. Combining US and DMSA scan, we found that the detection rate of high grade VUR was 95.3% and that of low grade was 62.5%. During follow up, most of the low grade VURs with normal DMSA and US scans resolved or were downgraded. Most high grade VURs could be detected by US and DMSA scan, but the prediction rate was not as high in low grade VURs. However, we can anticipate spontaneous improvement without complications in patients with either low or high grade reflux and negative findings on US and DMSA scan.