Borderline changes on biopsy can either be interpreted as a variant of normal or as a variant of acute rejection. Some investigators regard it as a sign of early acute rejection and initiate treatment accordingly. In this study, we evaluated Tc-99m DTPA renal scintigraphy findings in allograft recipients with borderline changes on biopsy. Tc-99m DTPA renal scintigraphy was evaluated in 125 patients with acute allograft dysfunction. This study included 10 recipients with borderline changes on biopsy. Ten renal transplant recipients with low-grade acute rejection were studied as control group. Tc-99m DTPA renal scintigraphy was performed either as a routine procedure during the early posttransplantation period or at a time when renal function tests were impaired. After intravenous injection of Tc-99m DTPA, images were acquired every second for 1 minute (perfusion) and every 30 seconds for 20 minutes. Images were interpreted visually with respect to perfusion pattern, concentration ability and parenchymal retention. Normal scintigraphy findings were observed in 6 recipients with borderline changes (60%) and in 4 patients with low-grade acute rejection (40%). Among the remaining 6 patients with acute rejection, 4 had normal perfusion together with a minimal decrease in concentration and minimal parenchymal retention. In 2 patients, in addition to functional impairment, there was also decreased perfusion. None of the patients with borderline changes had perfusion abnormality. The remaining 4 patients had mild functional impairment. In conclusion, a normal Tc-99m renal scintigraphy is more common among patients with borderline changes compared to those with low-grade acute rejection. Minimal functional impairment, when present, cannot be differentiated from that due to acute rejection. The results of scintigraphy might contribute to patient management protocol. A Tc-99m DTPA study without perfusion abnormality or with normal findings might be regarded as a variant of normal and left untreated.
Volume : 6
Issue : 4
Pages : 190
Department of Nuclear Medicine, and General Surgery and Transplantation, Baskent University Faculty of Medicine, Ankara, Turkey