Does Early Diabetic Kidney Damage Alter Renal Elasticity? An Ultrasound-Based, Two-Dimensional Shear Wave Elastography Study

Objective: Kidney damage caused by type 2 diabetes mellitus (T2DM) can reduce renal elasticity. Limited number of data exist indicating whether early kidney damage causes stiffening of renal tissue. This comparative study aims to assess kidney elasticity in T2DM patients with or without moderate albuminuria, using ultrasound-based two-dimensional shear wave velocity (2D-SWV) measurements. Methods: Fifty-seven cases (40 T2D patients with stage 1 or 2 chronic kidney disease and 17 age- and sex-matched healthy controls) were included in this single-center prospective study. The T2DM patients were divided into those with moderate albuminuria (n=22) and those without albuminuria (n=18). Bilateral renal parenchymal 2D-SWV values were measured (separately) in the upper, middle, and lower kidney regions. Group data were compared using the t-test or Mann-Whitney-U test (whichever appropriate). Inter-observer agreement was assessed by deriving the intra-class correlation coefficient. Results: There was no difference between the T2DM and control groups in terms of the median age [55.5 (50-62) vs. 55 (48.5-59.5) years, p=0.48] and sex ratio [18 (45%) males vs. 10 (58.8%) females, p=0.34]. The average regional 2D-SWV values were all similar between the groups (all p>0.05). The average 2D-SWV values were similar between the subgroups with and without albuminuria. The inter-observer agreement was good (intra-class correlation coefficient=0.66, 95% CI 0.19-0.88, p=0.006). Conclusion: Kidney elasticity does not seem to be compromised in patients with diabetes and preserved estimated glomerular filtration rate with or without moderate albuminuria.