[Vascular kidney transplant rejection--is a duplex sonographic diagnosis possible?]

The diagnostic value of quantitative Duplex Doppler sonography (DS) in renal allograft evaluation is being viewed increasingly critically. We undertook a retrospective analysis of DS in 51 consecutive patients to assess the capability of DS in the diagnosis of vascular rejection. At the time of renal allograft biopsy, a mean resistive index (RI) was calculated from Doppler measurements within main, segmental, interlobar and arcuate arteries and correlated with histological diagnosis. Our results indicate a low specificity (36% for RI greater than 0.7), low sensitivity (35% for RI greater than 0.9) as well as a low positive predictive value (54% for RI greater than 0.7) for the diagnosis of vascular rejection. Therefore, elevation of the RI is an unspecific finding in different causes of allograft dysfunction. Thus, renal biopsy to establish specific histologic diagnosis of allograft dysfunction remains mandatory.