Abstract

Background: The assessment of renal function is a major challenge in nuclear medicine, in particular for the diagnosis and followup of kidney’s pathologies. The technical scans using 99mTc-DMSA and the 99mTc-DTPA, are widely used to measure relative renal function (RRF). The 99mTc-DMSA provides a static analysis of the renal parenchyma and the detection of scars. The 99mTc-DTPA offers a dynamic approach in assessing the glomerular filtration rate (GFR). This study aims to compare these two methods in order to determine their degree of correlation and their possible interchangeability.
Methods : The study was conducted in the Nuclear Medicine Department of the Hospital General Idrissa Pouye in Dakar, on a sample of 42 patients whose average age was 3.38 years.
Results: The correlation analysis and bivariate analysis revealed a significant positive correlation (r = 0.996, p < 0.001) between the RRF calculated by the two methods. Following the diagnosis of patients, the ANOVA test showed no significant difference between the RRF calculated for the kidneys (left and right). The Bland-Altman plot analysis indicated a mean difference close to zero between the two methods, estimated at −0.43 for the right kidney and 0.43 for the left kidney. The limits of agreement range from −13.02 to 12.17 for the right kidney and −12.15 to 13.01 for the left kidney.
Conclusion: According to the results obtained in this study, the methods of scintigraphy using 99mTc-DMSA and the 99mTc-DTPA provide values of relative renal function on the (RRF) is almost identical, thus making them to be calculated systematically with the two techniques are not essential. The 99mTc-DMSA could be the choice of first-line for the evaluation of the RRF. However, if a measure of the GFR and an analysis of the curve of the rénogramme are necessary, the 99mTc-DTPA is a preferred option.

Key words: Relative renal function, 99mTc-DMSA, 99mTc-DTPA, Bland-Altman plot.