Shear wave elastography parameters adds prognostic value to adverse outcome in kidney transplantation recipients

Abstract

Introduction

The tissue stiffness of donor kidneys in transplantation may increase due to pathological changes such as glomerulosclerosis and interstitial fibrosis, and those changes associate worse outcomes in kidney transplantation recipients. Ultrasound elastography is a noninvasive imaging examination with the ability to quantitatively reflect tissue stiffness. Aim of this study was to evaluate the prognostic value of ultrasound elastography for adverse kidney outcome in kidney transplantation recipients.

Methods

Shear wave elastography (SWE) examinations were performed by two independent operators in kidney transplantation recipients. The primary outcome was a composite of kidney graft deterioration, all-cause re-hospitalization, and all-cause mortality. Survival analysis was calculated by Kaplan-Meier curves with the log-rank test and Cox regression analysis.

Results

A total of 161 patients (mean age 46 years, 63.4% men) were followed for a median of 20.1 months. 27 patients (16.77%) reached the primary endpoint. The mean and median tissue stiffness at the medulla (hazard ratio: 1.265 and 1.229, respectively), estimated glomerular filtration rate (eGFR), and serum albumin level were associated with the primary outcome in univariate Cox regression. Adding mean or median medulla SWE to a baseline model containing eGFR and albumin significantly improved its discrimination (C-statistics: 0.736 for the baseline, 0.766 and 0.772 for the model added mean and median medulla SWE, respectively).

Conclusion

The medullary tissue stiffness of kidney allograft measured by shear wave elastography may provide incremental prognostic value to adverse outcomes in kidney transplantation recipients. Including SWE parameters in kidney transplantation recipients management could be considered to improve risk stratification.

Keywords:

• Kidney transplantation
• shear wave elastography
• prognosis

Acknowledgement

Thanks to the innovative research team of high-level local universities in Shanghai for supporting the research.

Ethical approval

This study protocol was reviewed and approved by the ethnic committee of Renji Hospital, Shanghai Jiao Tong University, School of Medicine. Written informed consent was obtained from all participants.

Author contributions

Tian-yi Zhang: Methodology, Formal Analysis, Investigation, Writing - Original Draft Jiayi Yan: Data Curation, Funding Acquisition, Software, Visualization Jiajia Wu: Resources, Methodology, Validation Wenqi Yang: Software, Funding acquisition, Data Curation Shijun Zhang: Software, Visualization, Data Curation Jia Xia: Resources Xiajing Che: Resources Hongli Li: Supervision Dawei Li: Resources Liang Ying: Resources Xiaodong Yuan: Resources Yin Zhou: Supervision, Conceptualization Ming Zhang: Supervision, Conceptualization Shan Mou: Funding acquisition, Supervision, Conceptualization

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

Any inquiries toward the datasets generated and/or analyzed during the current study can be directed to the corresponding authors.

Additional information

Funding

This study was funded by National Natural Science Foundation of China [82170685, 81970574], Shanghai Municipal Commission of Health and Family Planning [ZY(2021-2023)-0208, ZY(2021-2023)-0302], Clinical Research Fund of Shanghai Municipal Health Commission [No. 20224Y0023], and Clinical Research Innovation and Cultivation Fund Project of Ren Ji Hospital, Shanghai Jiao Tong University School of Medicine [No. RJPY-LX-010].