The renal washout parameter as an indicator of transplant rejection.

The accumulation of intravascular fibrin thrombosis in both acute and chronic renal rejection leads to a delay in the transit of perfusion. This study examines the renal washout parameter as an indicator of transit time. By mathematical simulation of renal time-activity curves various factors which can influence this parameter are investigated, a simple analysis is proposed and clinical results are correlated with biopsy findings. A washout parameter greater than 28 s is found to be consistent with histologically diagnosed rejection over a range of bolus qualities.