Shear-Wave Elastography Variability Analysis and Relation with Kidney Allograft Dysfunction: A Single-Center Study

Area of Science:

• Nephrology
• Medical Imaging
• Transplantation Medicine

Background:

• Kidney allograft dysfunction is a significant concern post-transplantation.
• Accurate assessment of allograft function is crucial for patient management.
• Shear-wave elastography (SWE) is an emerging imaging technique for tissue stiffness evaluation.

Purpose of the Study:

• To evaluate the variability of kidney allograft stiffness using SWE.
• To determine if SWE can differentiate between stable kidney allograft function and allograft dysfunction.
• To explore correlations between allograft stiffness and patient characteristics.

Main Methods:

• A single-center prospective study included 63 patients undergoing renal transplantation.
• Eighty-three SWE examinations were performed on stable allografts (n=69) and allografts with dysfunction (n=14).
• Kidney allograft stiffness (Young's modulus in kPa) was measured in the cortex and medulla, with high intra- and inter-examination variability noted.

Main Results:

• Kidney allograft cortex stiffness was significantly higher in patients with allograft dysfunction (median 28.70 kPa) compared to those with stable function (median 20.99 kPa; p=0.0142).
• Allograft tissue stiffness negatively correlated with body mass index and positively correlated with the Proteinuria/Creatinuria ratio, particularly in stable allografts.
• Cortical stiffness was significantly higher in allograft dysfunction cases.

Conclusions:

• Shear-wave elastography demonstrates potential as a tool to identify kidney allograft dysfunction.
• Increased cortical stiffness is associated with allograft dysfunction.
• Further extensive studies are required to establish SWE as a standard clinical practice for kidney transplant evaluation.