99m Tc DTPA scan as a diagnostic marker of acute rejection in renal transplantation.

ABSTRACT

Forty renal transplant recipients were subjected to 99m Technicium Diethylene triamine pentacetic acid (DTPA)scans at regular intervals & whenever there was suspection of rejection. Serial scans of a group of 15 recipients from immediate post transplant period till withdrawal of cyclosporine were analysed separately & the results compared to with single scan analysis. The sensitivity & specificity of DTPA scan in the absence of acute tubular necrosis (ATN) was 94.1% & 87.5%, while the positive & negative predictive values were 88.8 & 93.3% respectively. Sensitivity & specificity of serial scan analysis (88.8% and 75%) in early post transplant period was higher than that of interpretation of single scan (75% & 66%). Serial scan changes predated clinical rejection during cyclosporine withdrawal period. We conclude that DTPA scan is both a sensitive & specific non-invasive diagnostic marker of acute rejection in absence of ATN & serial scans during early post transplant period & at the time of cyclosporine withdrawal are helpful in detecting the rejection accurately & at the earliest.