The Role of Late Dimercaptosuccinic Acid (DMSA) Scan and Renal Ultrasonography for Vesicoureteral Reflux in Older Children

Abstract

Aim:Vesicoureteral reflux (VUR) is an important risk factor for urinary tract infection (UTI). We aimed to investigate the relationships between VUR and ultrasound with late dimercaptosuccinic acid (DMSA) scan findings in children aged older than two years who had their first febrile UTI (FUTI).Materials and Methods:Data from those patients with their first FUTI were retrospectively analyzed. A late DMSA scan was performed at least 6 months after an acute FUTI. The late DMSA scans were graded as mild (focal defect in uptake), moderate (uptake of renal radionuclide from 20 to 40%), and severe (shrunken kidney with uptake less than 20%). Micturating cystourethrography was performed at 3 to 6 weeks after the FUTI.Results:The records of 220 patients (61 mild VUR, 60 severe VUR, 99 without VUR) were reviewed. An abnormal US was more common in those patients with VUR than those without VUR (p=0.009). Abnormal US had a sensitivity of 79.34% for VUR and 81.67% for severe VUR. The negative predictive value of renal US for severe VUR was 91.13%. The frequency of renal scarring was higher in those patients with VUR than for those without VUR (102/44, p=0.001). A logistic regression analysis showed significant associations between abnormal US and VUR or severe VUR (p=0.019 and p=0.011, respectively). Renal scarring had a sensitivity of 84.3% for VUR, and 91.67% for severe VUR.Conclusion:Late DMSA scan findings can predict the presence and grade of VUR in older children who have their first FUTI. Normal renal US can predict the absence of severe VUR.

Keywords

• febrile urinary tract infection
• late dmsa scan
• older children
• vesicoureteral reflux