Significance of 99mTc-dimercaptosuccinic Acid(DMSA) Renal Scan for Children with Urinary Tract Infection

Choi, Woong Ki; Han, Chang Hee; Yoon, Jai Young

Abstract

PURPOSE: Acute pyelonephritis in children may lead to permanent renal scarring with a risk of later hypertension and renal failure and so needs prompt diagnosis and appropriate treatment. The main aim of this study was to evaluate the value of 99mTc-dimercaptosuccinic acid(DMSA) renal scan in detecting renal involvement of acute urinary tract infection(UTI) and determining the sensitivity to find coexisting vesicoureteral reflux(VUR) in children.
MATERIALS AND METHODS
A total of 192 children(97 males, 95 females) admitted with bacteriologically proven and symptomatic UTI between May 1994 and April 1997 were analysed. DMSA renal scan was performed in all cases. 70 children underwent VCUG. Findings of DMSA renal scan were analysed according to age, sex, previous history of UTI and VUR.
RESULTS
89 children(46%) were under the age of 1 year. There was a preponderance of UTI in boys under the age of 1 year(66.3%) and in girls over the age of 1 year(63.1%). Of the 192 children studied, 155 children(80.7%, 81 males, 74 females) had first episode and the remaining 37 children(19%, 16 males, 21 females) had previous history of symptomatic UTI. Abnormalities in DMSA renal scan were found in 67(43.2%) of 155 children with the first UTI and in 30(89%) of 37 children with recurrent UTI. Bilateral DMSA abnormalities were noted in 8(5.2%) of 155 children with the first UTI and in 11(29.7%) of 37 children with recurrent UTI. Of the 70 children who underwent VCUG, VUR was seen in 41(58.6%) children. Of the 41 children with VUR, 31(90.2%) children had abnormal DMSA images. VUR was demonstrated in 37(75.5%) of 49 children with abnormal DMSA images and especially in 100% of 14 children with bilateral abnormal DMSA images.
CONCLUSIONS
A high proportion of abnormal DMSA images was found in children with recurrent UTI and children with VUR, especially high grade or bilateral reflux. DMSA renal scan is a sensitive method for evaluating the functional defect of involved kidney and predicting coexistent VUR according to its image appearance in patients with UTI.