Elsevier

Transplantation Proceedings

Volume 46, Issue 10, December 2014, Pages 3352-3357
Transplantation Proceedings

Frontiers in Transplantation
Kidney transplantation
Contrast-Enhanced Ultrasonography in the Early Period After Kidney Transplantation Predicts Long-Term Allograft Function

https://doi.org/10.1016/j.transproceed.2014.04.013Get rights and content

Abstract

Introduction

Real-time contrast-enhanced sonography (CES) can assess microvascular tissue perfusion using gas-filled microbubbles. The purpose of the study was to evaluate the feasibility of early CES in predicting long-term kidney allograft function in comparison to color Doppler ultrasonography (CDUS).

Methods

We prospectively studied 68 consecutive kidney transplant recipients using CES and conventional CDUS investigation 1 week after transplantation. Transplant tissue perfusion imaging was performed by low-power imaging during intravenous administration of the sonocontrast SonoVue. Renal tissue perfusion was assessed quantitatively using flash replenishment kinetics of microbubbles to estimate renal blood flow (RBF). The obtained sonography values were correlated with clinical data 1 week up to 1 year after transplantation.

Results

In contrast with conventional CDUS resistive indices, RBF estimated by CES 1 week posttransplantation significantly correlated with kidney function after 1 year (r = 0.67; P < .001). Determination of RBF by CES revealed a significant correlation with donor age but not recipient age, whereas conventional CDUS resistive index was significantly correlated to recipient age (r = 0.54; P < .001) but not donor age. Furthermore RBF was associated with vascular fibrosis and intimal thickening of the engraftment biopsies.

Conclusion

This is the first prospective study demonstrating the prognostic value of CES early after kidney transplantation. In contrast with CDUS, CES reveals information about kidney allograft perfusion independent of recipient vascular compliance.

Section snippets

Patients

This prospective, explorative single-center clinical trial all patients >18 years who underwent kidney transplantation at University Hospital Heidelberg between January 2011 and September 2011 were eligible for the study. The local ethical committee approved the study protocol (S-497/2010), and all patients gave written informed consent. Exclusion criteria were defined as renal artery stenosis or arteriovenous fistula of the allograft, screened by CDUS, the presence of aortal synthetic vascular

Patients

A total of 80 patients were eligible for the study. Seventy-one patients met inclusion criteria and were enrolled. Only 2 patients (2.94%) lost their graft during follow-up. Both patients suffered from refractory acute cellular rejection in the first month after kidney transplantation. There was no association to RRI; 1 patient had an RRI > 0.7 and 1 patient < 0.7, and RBF (1 patient > 12 dB/s, 1 patient < 12 dB/s), respectively. One patient died during the follow-up at month 10 after kidney

Discussion

The salient finding of the study is that RRI is not associated with characteristics of the kidney transplant, whereas RBF evaluated by CES is a prognostic marker for kidney allograft function after 12 months and associated with histologic findings of the engraftment biopsy, therefore reflecting characteristics of the kidney allograft itself.

In an earlier prospective study by Radermacher et al [3], it was postulated that an RRI of >0.8 was a prognostic marker of allograft and patient survival.

Acknowledgments

The authors thank Peter Nawroth, who helped to fund the study via a research grant from the Hopp-Stiftung.

References (31)

  • F. Vincenti et al.

    A phase III study of belatacept-based immunosuppression regimens versus cyclosporine in renal transplant recipients (BENEFIT study)

    Am J Transplant

    (2010)
  • K.S. Allen et al.

    Renal allografts: prospective analysis of Doppler sonography

    Radiology

    (1988)
  • B. Krumme et al.

    Determinants of intrarenal Doppler indices in stable renal allografts

    J Am Soc Nephrol

    (1997)
  • J. Radermacher et al.

    The renal arterial resistance index and renal allograft survival

    N Engl J Med

    (2003)
  • S. Seiler et al.

    Ultrasound renal resistive index is not an organ-specific predictor of allograft outcome

    Nephrol Dial Transplant

    (2012)
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    V.S. and V.H. contributed equally to this work.

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