Dimercapto-succinic acid scintigraphy instead of voiding cystourethrography for infants with urinary tract infection

PURPOSE: We study the ability of dimercapto-succinic acid (DMSA) scintigraphy to predict the presence of dilating vesicoureteral reflux (VUR) in infants with urinary tract infection (UTI) to simplify the evaluation protocol. MATERIALS AND METHODS: A retrospective analysis of the records of 303 children younger than 2 years with initial UTI investigated with DMSA scintigraphy and voiding cystourethrography (VCU) within 3 months after UTI was performed. RESULTS: In 156 of the 303 children (51%) DMSA scintigraphy showed renal lesions. VUR was found in 80 patients (26%) and VUR grade significantly correlated with the presence of renal lesions. A normal DMSA scintigraphy and dilating VUR (grade III) occurred in 7 infants. At followup after 1 to 2 years, 6 of these 7 patients had normal DMSA scans and 1 had a scarred duplex kidney. VUR resolved spontaneously in 5 and improved spontaneously to grade 1 in 2 patients. None of the 7 children had recurrent UTI. CONCLUSIONS: DMSA scintigraphy in infants with UTI may replace VCU as a first line investigation. A strategy to perform VCU in only patients with renal lesions is proposed. In this study 147 of 303 VCUs would have been unnecessary as only 1 child with a damaged kidney was missed.