Prospective Study
Copyright ©The Author(s) 2024. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Radiol. Dec 28, 2024; 16(12): 782-793
Published online Dec 28, 2024. doi: 10.4329/wjr.v16.i12.782
Role of multi-parametric ultrasonography for the assessment and monitoring of functional status of renal allografts with histopathological correlation
Hira Lal, Surojit Ruidas, Raghunandan Prasad, Anuradha Singh, Narayan Prasad, Anupma Kaul, Dharmendra S Bhadauria, Ravi S Kushwaha, Manas R Patel, Manoj Jain, Priyank Yadav
Hira Lal, Surojit Ruidas, Raghunandan Prasad, Anuradha Singh, Department of Radiology, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow 226014, Uttar Pradesh, India
Narayan Prasad, Anupma Kaul, Dharmendra S Bhadauria, Ravi S Kushwaha, Manas R Patel, Department of Nephrology, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow 226014, Uttar Pradesh, India
Manoj Jain, Department of Pathology, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow 226014, Uttar Pradesh, India
Priyank Yadav, Department of Urology and Renal Transplantation, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow 226014, Uttar Pradesh, India
Author contributions: Lal H, Ruidas S, Prasad R, Bhadauria DS, Patel MR, Kaul A, and Kushwaha RS designed and coordinated the study; Lal H, Ruidas S, Prasad R, and Singh A performed the examinations, acquired and analyzed the data; Lal H, Ruidas S, and Singh A interpreted the data; Lal H, Ruidas S, and Yadav P wrote the manuscript; Lal H, Ruidas S, Prasad N, Yadav P, and Singh A performed the statistical analysis; All authors approved the final version of the article.
Institutional review board statement: The study was reviewed and approved by institutional review board of SGPGIMS, Lucknow, India (IEC code: 2019-14-MD-EXP-6/PGI/BE/159/2019; Date: 08.03.2019).
Clinical trial registration statement: No clinical trial registration was established for this study.
Informed consent statement: All study participants provided written consent prior to study enrollment.
Conflict-of-interest statement: The authors of this manuscript have no conflicts of interest to disclose.
Data sharing statement: There are no additional data available.
CONSORT 2010 statement: The authors have read the CONSORT 2010 Statement, and the manuscript was prepared and revised according to the CONSORT 2010 Statement.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Priyank Yadav, MCh, Assistant Professor, Department of Urology and Renal Transplantation, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Raibareli Road, Lucknow 226014, Uttar Pradesh, India. priyankmamc@gmail.com
Received: May 27, 2024
Revised: November 3, 2024
Accepted: November 19, 2024
Published online: December 28, 2024
Processing time: 214 Days and 0.1 Hours
Abstract
BACKGROUND

The study focuses on the use of multi-parametric ultrasound [gray scale, color Doppler and shear wave elastography (SWE)] to differentiate stable renal allografts from acute graft dysfunction and to assess time-dependent changes in parenchymal stiffness, thereby assessing its use as an efficient monitoring tool for ongoing graft dysfunction. To date, biopsy is the gold standard for evaluation of acute graft dysfunction. However, because it is invasive, it carries certain risks and cannot be used for follow-up monitoring. SWE is a non-invasive imaging modality that identifies higher parenchymal stiffness values in cases of acute graft dysfunction compared to stable grafts.

AIM

To assess renal allograft parenchymal stiffness by SWE and to correlate its findings with functional status of the graft kidney.

METHODS

This prospective observational study included 71 renal allograft recipients. Multi-parametric ultrasound was performed on all patients, and biopsies were performed in cases of acute graft dysfunction. The study was performed for a period of 2 years at Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, a tertiary care center in north India. Independent samples t-test was used to compare the means between two independent groups. Paired-samples t-test was used to test the change in mean value between baseline and follow-up observations.

RESULTS

Thirty-one patients had experienced acute graft dysfunction at least once, followed by recovery, but none of them had a history of chronic renal allograft injury. Mean baseline parenchymal stiffness in stable grafts and acute graft dysfunction were 30.21 + 2.03 kPa (3.17 + 0.11 m/s) and 31.07 + 2.88 kPa (3.22 + 0.15 m/s), respectively; however, these differences were not statistically significant (P = 0.305 and 0.252, respectively). There was a gradual decrease in SWE values during the first 3 postoperative months, followed by an increase in SWE values up to one-year post-transplantation. Patients with biopsy-confirmed graft dysfunction showed higher SWE values compared to those with a negative biopsy. However, receiver operating characteristic analysis failed to show statistically significant cut-off values to differentiate between the stable graft and acute graft dysfunction.

CONCLUSION

Acute graft dysfunction displays higher parenchymal stiffness values compared to stable grafts. Therefore, SWE may be useful in monitoring the functional status of allografts to predict any ongoing dysfunction.

Keywords: Shear wave elastography; Renal allograft; Renal transplant; Acute graft rejection; Resistive index; Multi-parametric ultrasound

Core Tip: This prospective study showed that mean shear wave elastography (SWE) and interlobar artery resistive index values were slightly higher in patients with acute graft dysfunction compared to stable grafts. Grafts with biopsy-confirmed dysfunction showed slightly higher values than biopsy negative grafts. Therefore, SWE may be a valuable imaging modality for the assessment of renal allograft pathology and their monitoring if combined with routine ultrasonography. Further evaluation on a larger more diverse sample cohort should be performed.