Factors Influencing Renal Parenchymal Stiffiness in Patients with Diabetic Nephropathy

OBJECTIVE: Glomerulosclerosis and tubulointerstitial fibrosis are associated with lower renal parenchymal resilience. The purpose of this study is to determine the factors influencing renal resilience in patients with diabetic nephropathy (DN). METHODS: We recruited 56 healthy volunteers and 187 patients with DN. All the participants were evaluated using shear-wave elastography (SWE), and the size of their kidneys and Young’s modulus values for the parenchyma were recorded. A total of 187 patients with DN are allocated to three groups according to their urinary albumin-to-creatinine ratio: normoalbuminuric (<30 mg/g creatinine), microalbuminuric (30–300 mg/g), and macroalbuminuric (≥300 mg/g) groups. Renal resilience is compared between the stages of diabetic nephropathy and the healthy control group, and the factors affecting the stiffiness of the renal parenchyma in DN are analyzed. RESULTS: The renal parenchyma is harder in participants with DN than in healthy participants (P < 0.001), and the stiffiness increases with the progression of the disease (P < 0.001). Multivariate logistic regression analysis shows that disease stage (β = 0.789, P < 0.001), duration of diabetes (β = 0.028, P < 0.001), and serum creatinine (SCr) concentration (β = 0.001, p < 0.001) influence the stiffiness of the renal parenchyma. CONCLUSION: We show that SWE can be used to measure changes in the stiffiness of the renal parenchyma in patients with DN. Furthermore, Young’s modulus of the renal parenchyma is related to the duration of diabetes, urinary albumin excretion, and SCr concentration. Thus, SWE can be used to objectively and non-invasively stage DN.