OBJECTIVE: To standardize a method and determine normal values for absolute renal uptake of 99mTc-DMSA in children with normal creatinine clearance. MATERIALS AND METHODS: Twenty-two children (between 7 months and 10 years of age; mean 4.5 years) without clinical evidence of renal disease were studied using 99mTc-DMSA scintigraphy. Eighteen had normal renal ultrasonography, micturating urethrocystography, creatinine clearance and visual interpretation of the scintigraphy with 99mTc-DMSA. Four children were excluded, one with incomplete creatinine clearance and three due to reduction in the creatinine clearance. Absolute renal uptake of 99mTc-DMSA (DMSA-Abs) was expressed as the fraction of the administered dose retained by each kidney six hours after administration of the radiopharmaceutical. RESULTS: DMSA-Abs was 21.8 ± 3.2% for the right kidney and 23.1 ±3.3% for the left kidney. There was no correlation between renal uptake and the age groups studied, although there was a tendency to an increase in the creatinine clearance with age. CONCLUSION: Normal values of DMSA-Abs can be used as an additional parameter for the initial diagnostic evaluation and during follow-up of renal diseases, mainly when bilateral impairment of renal function is suspected or in a patient with a single functioning kidney (in which renal differential function is of limited value).

Keywords: Renal function, Quantification, 99mTc-DMSA, Children, Scintigraphy