Intrarenal resistive index after renal transplantation

A recent paper in the New England Journal of Medicine from a group in the Netherlands led by the late Yves Vanrenterghem has reported a very careful investigation of the intrarenal Resistive Index in renal allografts using Doppler ultrasonography. The resistive index was measured at baseline and at regular intervals after transplantation at the time of protocol biopsies and at the time of any biopsies performed because of graft dysfunction. All patients have been followed for at least 4.5 years after transplantation and basically the results show that the resistive index reflects characteristics of the recipient, but not those of the graft which  had been the expectation behind the investigation based on studies of native kidneys.