Application of shear wave elastography in the study of renal tissue elasticity in patients with diabetic nephropathy

Abstract

Objective To investigate the clinical value of real-time shear wave elastography(SWE) in early diagnosis of diabetic nephropathy(DN). Methods One hundred and fifty-five patients with type 2 diabetes mellitus (DM) in our hospital were selected as DN group and 54 healthy volunteers with matched age-sex were selected as control group. According to the criteria of Mogensen staging, patients of DN group were divided into 3 subgroups according to urine protein/creatinine (ACR): group A (DM or DN Ⅰ, Ⅱ), ACR 300 mg/g. All subjects were examined by SWE technique to detect the maximum, mean and minimum Young′s modulus values (Emax, Emean, Emin) of the middle of left renal parenchyma, the values of Young′s modulus in the control group and DN patients were compared. The relationship between Young′s modulus and ACR in patients with DN was analyzed. Results The Emax, Emean and Emin in DN patients were all greater than those in control group (P<0.05). In group A, B and C, Emax, Emean and Emin gradually increased (P<0.05). Spearman correlation analysis showed that there was a positive correlation between Young′s modulus and ACR in patients with DN (r=0.817, 0.764, 0.609; all P=0.000). ROC curve analysis showed that the area under the curve of Emax diagnosis DN Ⅲ stage was 0.810, the cut-point value was 6.65 kPa, the sensitivity was 79.0%, and the specificity was 81.7%; the area under the curve of Emean diagnosis DN Ⅲ stage was 0.785, and the cut-off value was 3.69 kPa, sensitivity 62.8%, specificity 78.3%. Conclusions SWE technique can quantitatively analyze renal parenchyma hardness in patients with different stages of DN, which may provide new diagnostic information for early diagnosis of DN. Key words: Ultrasonography; Diabetic nephropathy; Shear-wave elastography; Renal parenchyma elasticity