CONTRAST NEPHROTOXICITY AND THE ROLE OF RADIONUCLIDE RENAL SCAN

Radiographic contrast media-induced nephrotoxicity is an important cau se of acute renal failure. The indications of using contrast are usual ly unavoidable, compelling and continue to expand, especially in the v ascular field. When acute renal failure follows such a procedure, it b ecomes important to establish the presence of contrast nephrotoxicity or an acute occlusive event which may have precipitated the failure. W e present two cases of contrast nephrotoxicity in patients with impair ed renal function. Radionuclide renal studies with Tc-99m-DTPA (Patien t 1) and Tc-99m-MAG3 (Patient 2), confirmed the presence of acute tubu lar necrosis and excluded major occlusive vascular events. Renal scint igraphy remains an important but underused test which can rule out obv ious renal vascular occlusion and/or support the diagnosis of contrast -related acute tubular necrosis, as the cause of renal failure in thes e patients.