Diagnostic Value of 99mTc-DMSA SPECT in Children with Urinary Tract Infection

Choi, Jae Won; Cha, Sung Ho; Cho, Byoung Soo; Kim, Duk Yoon

Abstract

PURPOSE
The accurate identification of renal cortical defects in children with urinary tract infection is essential in reducing subsequent morbidity. Imaging of the kidneys with 99mTc-dimercaptosuccinic acid (DMSA) has been demonstrated as the sensitive method available for identification of renal cortical defects. Single photon emission computerized tomography (SPECT) has been suggested as a method by which the accuracy of identification of renal cortical defects can be improved. The aim of this study was to assess the diagnostic value of the 99mTc-DMSA SPECT, comparing the detection rate of cortical defects identified from planar imaging and SPECT data.
METHODS
99mTc-DMSA SPECT, planar imaging and voiding cystourethrogram (VCUG) were performed in 76 patients diagnosed urinary tract infection at the department of pediatrics, Kyung Hee University Hospital, from March, 1994 to Feburary, 1995. Follow-up 99mTc-DMSA SPECT was done in 7 patients.
RESULTS
1) Overall detection rate of 99mTc-DMSA SPECT imaging was 32.9% (25/76), but, planar imaging showed cortical defects in 21.1% (16/76). 2) The patients with renal cortical defects in planar imaging showed all definite or more additional cortical defects in 99mTc-DMSA SPECT imaging. 3) Seven patients presented improvement in 4, no change in 2, and aggrevation in 1 on follow-up studies. 4) Incidence of renal cortical defects was higher in patients with vesicoureteral reflux (VUR); the detection rate was 83.3% (10/12). But, those of without VUR also presented high detection rate as 23.4% (19/60). 5) There is no correlation between renal cortical defects and urine culture findings.
CONCLUSIONS
99mTc-DMSA SPECT imaging is superior to planar imaging, thus 99mTc-DMSA SPECT is a useful initial diagnostic tool in children suggesting urinary tract infection, irrespective of VUR, to identify patients who need more extensive radiological studies and early treatment.