Performance of technetium-99m mercaptoacetyltriglycine scintigraphy in evaluation of renal parenchymal lesions: A comparative study with technetium-99m dimercaptosuccinic acid

Abstract

Objective: Technetium (Tc) -99 m dimercaptosuccinic acid (DMSA) scintigraphy is accepted as a gold standard method in the evaluation of renal parenchymal lesions and split renal function (SRF). However, the high radiation exposure on the part of the renal cortex is its strongest disadvantage, especially in young children. Because of its high excretion rate from the kidneys ,the radiation exposure rate is significantly lower with Tc-99m mercaptoacetyltriglycine (MAG3) than with Tc-99 m DMSA. In addition to its use in evaluating renal perfusion and function ,Tc-99m MAG3 is helpful in assessing cortical lesions. We aimed to assess the performance of Tc-99m MAG3 analysis in comparison to DMSA scintigraphy for the assessment of renal parenchymal lesions and SRF in children. Methods: During the 5-year period, 101 pediatric patients (54 boys and 47 girls) ranging from 2 months to 18 years in age (mean age ± SE, 5 ±4 and median age ,4 years) who underwent renal cortical scintigraphy and function analysis were included in this retrospective study. Both DMSA and MAG3 studies were performed within one to three weeks of each other. The renal parenchymal findings and SRF results for both kidneys obtained with the Tc-99m MAG3 scintigraphy were compared to the results of Tc-99m DMSA testing. Results: There was a high correlation between the two studies in terms of diagnosing SRF (r =0.98 ,P =0.01). The sensitivity for Tc-99m MAG3 was found to be 96% ,its specificity was 65% ,and its accuracy was 84% for the detection of renal parenchymal defects. Conclusion: Regarding the evaluation of kidney perfusion and function ,Tc-99m MAG3 scintigraphy is useful for the evaluation of SRF and renal parenchymal lesions ,but its performance is poorer than Tc-99m DMSA. Therefore, we do not recommend that it replace Tc-99m DMSA during initial diagnosis and follow-up of renal parenchymal lesions.