An evaluation of the use of sup(99m)Tc-dimercaptosuccinic acid in the determination of divided renal function

The value of sup(99m)Tc-dimercaptosuccinic acid (sup(99m)Tc-DMSA) in the determination of divided renal function was analyzed in 91 patients with renal vascular diseases,tumours, glomerulonephritis, pyelonephritis and ureteric obstruction. Scintigraphy and renography with 131I-Hippuran were used as the standard of reference. There was a close correlation between the uptake of sup(99m)Tc-DMSA in the right kidney 2 and 6 hours after I.V. administration (r=0.86, N = 17, p<0.001). Similarly, the 2-hour uptake of sup(99m)Tc-DMSA was significantly correlated with the 131I-Hippuran uptake (r = 0.90, N = 25, p<0.001). The 45-min uptake of sup(99m)Tc-DMSA was closely correlated with the 131I-Hippuran uptake when the renography was performed with a gamma camera (r = 0.96, N = 45, p<0.001) or with a 3-probe system (r = 0.96, N = 21, p<0.001). The results show that sup(99m)Tc-DMSA is useful in the determination of divided renal function irrespective of scintigraphy being performed 45 min, 2 and 6 hours after injection. Hydronephrosis can be a source of error. sup(99m)Tc-DMSA has the advantage of giving higher count-rates than 131I-Hippuran which results in better numerical statistics and more informative pictures. (author)