Diagnostic utility of renal shear wave elastography and renal Doppler findings in diabetic nephropathy: a case–control study

Background Diabetes mellitus is a common systemic disease that affects the kidneys and could eventually develop an end-stage renal failure. Renal biopsy is considered a gold standard for histological characterization of diabetic nephropathy, of which renal fibrosis is a dominant component, affecting its stiffness. The objective of this study is to investigate a correlation between renal stiffness obtained by shear wave elastography, renal Doppler resistivity indices, laboratory findings, and the histological characterization depicted by renal biopsies (if feasible) in diabetic nephropathy patients and to compare their results with those obtained from normal population to explore the diagnostic efficacy of shear wave elastography. Shear wave elastography and color duplex US were performed in twenty-six diabetic nephropathy patients and twenty-six healthy (age and sex-matched) control subjects. The shear wave elastography-derived mean value of the renal tissue stiffness was measured (in kilopascals) as well as the resistivity indices of segmental renal arteries, and then the mean values were correlated to patients' clinical-laboratory data (serum creatinine and albumin/ creatinine ratio) and the biopsy results, if feasible. Results A significant positive correlation was found between the mean resistivity indices and the mean renal cortical stiffness at one hand and the patients' clinical-laboratory data with statistically significant differences found between the control, early, and late stages of diabetic nephropathy. Conclusions Shear wave elastography is a promising, non-invasive, and accurate diagnostic tool for assessment and differentiation between early and late stages of diabetic nephropathy with a significant positive correlation to the clinical-laboratory and renal Doppler findings.