Prediction of Long-Term Renal Transplant Allograft Function From Day 3 Post-transplant Tc-99m MAG3 Scintigraphy

Abstract

PURPOSE: Serum creatinine (sCr) levels of >1.5mg/dL or >130 ummol/L at 1 year after renal transplantation were strongly predictive of long-term allograft survival. A Tc-99m MAG3 study with a Hilson's perfusion index (PI) is routinely performed on day 3 post-transplantation at Princess Alexandra Hospital, Australia. The predictive power of day 3 post-transplantation Hilson's PI for long-term sCr levels; and early sCr levels (at 1 or 3 months) to predict sCr levels at 12 months post-transplantation were studied. MATERIALS AND METHODS: One hundred eight patients receiving renal transplantation from April 2001 to March 2002 were retrospectively analyzed. sCr levels at 1, 3, and12 months, and 5 years after renal transplantation were recorded and compared with the day 3 post-transplantation Hilson's PI. RESULTS: Accuracy of 72% to 74%, and 90% sensitivity were recorded between Hilson's PIs and sCr levels up to 12-month post-transplantation. Spearman's correlation shows a significant relationship (R = 0.32-0.39, P = 0.00002-0.003). However, the association seems to have low specificity. A significant relationship was found for early sCr levels (at 1 or 3 months) to predict sCr levels at 12-month post-transplantation, with a Spearman correlation coefficient (R = 0.68-0.85, P < 0.000001). CONCLUSION: There is a strong relationship between the day 3 Hilson's PIs and serial sCr levels post-transplantation, and between the early sCr levels (1 and 3 months), and the 12 months sCr levels post-transplantation. A composite index integrating these 2 markers to predict long-term renal allograft survival remains to be investigated.