Quantitative SPECT of technetium-99m-DMSA uptake in the kidneys of normal children and in kidneys with vesicoureteral reflux: detection of unilateral kidney disease.

Abstract

Quantitative SPECT was used to evaluate renal functional volume (cc), percent of injected dose/cc (%ID/cc) and renal uptake (%) in 11 children with unilateral vesicoureteral reflux grade 3 or greater, and in 19 normal control children without reflux. Studies were performed 4-6 hr after intravenous injection of 0.750-2 mCi of 99mTc-DMSA. Control kidneys (n = 38) had a volume of 99.7 +/- 29.5 cc. The %ID/cc was 0.27 +/- 0.08, and the uptake in one kidney was 24.8% +/- 3.9%. Global renal uptake (right plus left) was 49.6% +/- 7.3%. Functional volume of the control kidneys showed an increase with age, and the %ID/cc showed a steeper decrease with age, resulting in a trend of the kidney uptake to decrease with age. Kidneys with reflux had a decreased kidney uptake of 15.7% +/- 29.5%, compared to age- and sex-matched controls (t = 4.7, p < 0.001). The contralateral kidneys without reflux had a significantly increased total uptake of 33.4% +/- 6.8% as compared to controls (t = 3.44, p < 0.01). Global uptake by the kidneys was 49.2% +/- 8.6% and was not statistically different from controls (t = 1.0, ns). Our results suggest that SPECT quantitation of 99mTc-DMSA uptake in each kidney separately could be used as a noninvasive method to assess impairment and compensation of the function of the individual kidney in children with vesicoureteral reflux.