EVALUATION OF TECHNETIUM-99M-L,L-EC IN RENAL-TRANSPLANT RECIPIENTS - A COMPARATIVE-STUDY WITH TECHNETIUM-99M-MAG3 AND IODINE-125-OIH

The clinical usefulness of kit-formulated (TC)-T-99m-L,L-EC, a new renal tubular tracer agent based on a diaminodithiol ligand was evaluated in a large population of renal transplant recipients. Methods: Fifty patients with transplants were studied. Five patients with renal insufficiency and five normal volunteers were also included to extend the range of renal function values. The labeling efficiency of Tc-99m-L,L-EC in routine conditions, i.e., without HPLC purification, and the safety of the tracer were evaluated. Results: The mean radiochemical purity of Tc-99m-L,L-EC determined by thin-layer chromatography was 97.4%. No side effects or significant biochemical changes were observed. The clearance of Tc-99m-L,L-EC and I-125-OIH ranged from 10.7 to 417.5 and from 27.6 to 602.7 ml/min/1.73 m(2), respectively The clearance of Tc-99m-L,L-EC and Tc-99m-MAG3 averaged respectively 71% and 52% of that of I-125-OIH. Conclusion: The labeling procedure of kit-formulated Tc-99m-L,L-EC is easy and efficient. This tracer is safe and suitable for both imaging and quantitative measurement of the renal tubular function. Technetium-99m-L,L-EC represents an excellent alternative to Tc-99m-MAG3.