Resistive Index Measurements After Kidney Transplantation

Correlation Between Renal Vascular Resistive Index, Renal Allograft Histology and Outcome

The purpose of this study is to evaluate the prognostic performance of intrarenal resistive index in the first years after kidney transplantation on graft function and on patient and graft survival. In addition, the determinants of the intrarenal resistive index, including a detailed analysis of the relation between graft histology and the intrarenal resistive index, will be assessed.

Study Overview

• Status: Completed
• Conditions: Kidney Failure

Detailed Description

Since March 2004, and as part of routine clinical practice, protocol renal allograft biopsies are routinely performed at implantation and at 3, 12 and 24 months after transplantation, in all patients who receive a kidney transplant at the University Hospitals Leuven, unless there is a medical contra-indication or patient refusal to undergo this procedure. The biopsies are scheduled using a dedicated Microsoft Access database ("Biopsy Database"), that is maintained on the central servers of the University Hospitals Leuven. Patients who have an unexplained change in renal allograft function, undergo additional clinically indicated indication biopsies. These biopsies are also recorded in the aforementioned Microsoft Access Database.

All clinical data, including pretransplant donor and recipient characteristics, and post-transplant follow-up data are directly stored and maintained in a prospectively collected electronic database (CCL database until 06/2012, transferred to the central KWS database in 2012). This electronic database is the only existing clinical database for these patients, and contains all clinical patient charts. No written records are collected.

All renal allograft biopsies will be rescored by a single renal pathologist according to the most recent Banff classification, blinded for the clinical parameters and timing of the biopsy. These rescoring data are directly entered in the dedicated Microsoft Access database ("Biopsy Database").

Just prior to performing a renal allograft biopsy with ultrasound guidance, and as part of the routine clinical procedure, duplex measurements are performed by the radiologist who will perform the biopsy. The peak systolic velocity (Vmax) and the minimal diastolic velocity (Vmin) are determined in each patient in two to three representative interlobar arteries. The resistive index is calculated as [1 - (V min/V max)]. This procedure is repeated at three different places in the kidney (lower, interpolar and upper pole). These data are directly entered in the central electronic clinical database system (KWS, see above).

All electronic data will be transferred to a SAS database at time of data extraction.

• Study Type: Observational
• Enrollment (Actual): 346

Contacts and Locations

Study Locations

• Belgium
  • Leuven, Belgium, 3000
    • Universitaire Ziekenhuizen Leuven

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Probability Sample

Study Population

All de novo renal allograft recipients transplanted at the University Hospitals Leuven between March 2004 and October 2007

Description

Inclusion Criteria:

Single kidney transplantation

Exclusion Criteria:

None

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort
Kidney transplant recipients; All de novo renal allograft recipients transplanted at the University Hospitals Leuven between March 2004 and October 2007

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Overall renal allograft survival	7 years after transplantation
Death-censored graft survival	7 years after transplantation
Patient survival	7 years after transplantation
Reduction of 50% or more in the eGFR from the value measured at the time of ultrasonography	7 years after transplantation

Collaborators and Investigators

• Sponsor: Universitaire Ziekenhuizen KU Leuven
• Investigators: Principal Investigator: Maarten Naesens, MD PhD, Universitaire Ziekenhuizen KU Leuven

Publications and helpful links

General Publications

• Naesens M, Heylen L, Lerut E, Claes K, De Wever L, Claus F, Oyen R, Kuypers D, Evenepoel P, Bammens B, Sprangers B, Meijers B, Pirenne J, Monbaliu D, de Jonge H, Metalidis C, De Vusser K, Vanrenterghem Y. Intrarenal resistive index after renal transplantation. N Engl J Med. 2013 Nov 7;369(19):1797-806. doi: 10.1056/NEJMoa1301064.

Study record dates

Study Major Dates

• Study Start: March 1, 2004
• Primary Completion (Actual): June 1, 2012
• Study Completion (Actual): June 1, 2012

Study Registration Dates

• First Submitted: June 10, 2013
• First Submitted That Met QC Criteria: June 12, 2013
• First Posted (Estimate): June 17, 2013

Study Record Updates

• Last Update Posted (Estimate): June 17, 2013
• Last Update Submitted That Met QC Criteria: June 12, 2013
• Last Verified: June 1, 2013

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Kidney Diseases; Urologic Diseases; Renal Insufficiency
• Other Study ID Numbers: KidneyTX-UZLEUVEN-RI