Renal cortical shear wave elastography across chronic kidney disease stages

Chronic kidney disease (CKD) progression is characterized by tubulointerstitial fibrosis, vascular remodeling and nephron loss, while conventional ultrasonography primarily detects later structural changes and does not directly quantify tissue biomechanics. Therefore, it is of interest to evaluate the renal cortical shear wave elastography (SWE) across CKD stages in 125 adults, with bilateral renal length, cortical thickness, echogenicity and five technically acceptable cortical SWE measurements from each kidney assessed alongside CKD-EPI estimated glomerular filtration rate (eGFR). Renal cortical stiffness increased progressively from stage 1 (4.12 +/- 0.82 kPa) to stage 5 (10.02 +/- 2.20 kPa; p < 0.001), correlated inversely with eGFR and correlated directly with serum creatinine and urea. A stiffness threshold of 7.44 kPa identified advanced CKD with an AUC of 0.924, 89.4% sensitivity, 82.1% specificity, 77.8% positive predictive value, 91.3% negative predictive value and 85.6% accuracy, with close concordance between right and left renal measurements. Thus, renal cortical stiffness increased with worsening CKD stage and showed high diagnostic performance for advanced disease, supporting SWE as a potential adjunct to biochemical and conventional ultrasound assessment when standardized acquisition protocols are used.