Role of shearing wave elastography in detecting early diabetic nephropathy.

Background: Diabetes mellitus is one of the systemic diseases affecting the kidneys that eventually develop end-stage kidney disease. Shear wave elastography (SWE) is a reliable and non-invasive ultrasonography test used to determine tissue elasticity. The aim of this study is to detect early diabetic nephropathy by measuring renal stiffness using shear wave elastography (SWE), renal resistivity indices, and laboratory findings in DN patients.

Methods: Shear wave elastography and color duplex sonography assessments were performed in 60 diabetic nephropathy patients (divided according to eGFR into 3 stages: stage I-II-III diabetic nephropathy with equal groups of 20 patients in each stage) and 20 healthy age-matched control subjects. The SWE-derived mean value of the tissue stiffness, given in kilopascals (kPa), was correlated to patients' clinico-laboratory data (serum creatinine and eGFR) and resistive index.

Results: There is a statistically significant increase in SWE and RI in the diabetic group than control group and a statistically significant increase in SWE (mean) in CKD stage II and III when compared with CKD stage I, SWE can be used to discriminate between diabetic groups and control group at a cutoff level of > 10.5 (kPa), and also, SWE (mean) can be used to discriminate between CKD stage II and III patients at a cutoff level of > 41 (kPa), with 66.7% sensitivity and 64.9% specificity.

Conclusion: Shear wave elastography is a sensitive, non-invasive, and specific diagnostic tool for the detection of diabetic nephropathy and differentiation between different stages of DN.