Shear wave elastography accurately detects chronic changes in renal histopathology

Area of Science:

• Nephrology
• Medical Imaging
• Biophysics

Background:

• Chronic kidney disease (CKD) is characterized by progressive renal fibrosis, impacting kidney stiffness.
• Renal biopsy is the standard for assessing histological damage, but it is invasive.
• Non-invasive methods to evaluate renal fibrosis are needed.

Purpose of the Study:

• To investigate the correlation between kidney stiffness measured by shear wave elastography (SWE) and histological renal fibrosis in CKD patients.
• To assess SWE's accuracy in detecting renal damage associated with glomerular sclerosis, interstitial fibrosis, and tubular atrophy.

Main Methods:

• Shear wave elastography (SWE) was performed on 75 CKD patients undergoing renal biopsy.
• Tissue Young's modulus (YM) in kilopascals (kPa) was measured using SWE.
• YM was correlated with histological scores for glomerular, tubulointerstitial, and vascular damage.

Main Results:

• Young's modulus (YM) showed significant correlation with tubulointerstitial (ρ = 0.442) and glomerular (ρ = 0.375) scores.
• Mean YM was lower in patients without glomerular sclerosis and increased with interstitial fibrosis and tubular atrophy.
• The area under the ROC curve for SWE differentiating mild vs. moderate kidney impairment was 0.702.

Conclusions:

• Shear wave elastography (SWE) accurately detects chronic renal damage.
• SWE correlates with glomerular sclerosis, interstitial fibrosis, and tubular atrophy.
• An optimal cut-off YM value of ≥5.81 kPa can identify significant renal damage.