Soluble urokinase plasminogen activator receptor as a diagnostic marker of early diabetic nephropathy and its capacity as a biomarker for renal impairment severity in patients with type 2 diabetes mellitus

Background Serum soluble urokinase plasminogen activator receptor (suPAR) has emerged as a potential biomarker of renal inflammation and fibrosis. Elevated suPAR levels have been associated with increasing albuminuria and declining estimated glomerular filtration rate in patients with type 2 diabetes mellitus (T2DM). Aim To evaluate serum suPAR levels (pg/ml) as an early diagnostic biomarker for diabetic nephropathy (DN) and to assess its relationship with albuminuria, renal function parameters, and disease severity. Patients and methods This observational cross-sectional case–control study included 80 participants divided into four groups: T2DM without nephropathy ( n =20), T2DM with albuminuria without renal impairment ( n =20), T2DM with albuminuria and renal impairment ( n =20), and healthy controls ( n =20). Serum suPAR was measured using an enzyme-linked immunosorbent assay. Correlation and receiver operating characteristic curve analyses were performed. Results Median serum suPAR levels were significantly higher in patients with albuminuria and renal impairment compared with other groups ( P <0.001). Serum suPAR showed significant positive correlations with serum creatinine, blood urea, fasting and postprandial glucose levels, and albumin-to-creatinine ratio, and a significant negative correlation with estimated glomerular filtration rate (all P <0.05). Receiver operating characteristic analysis demonstrated good diagnostic performance of suPAR for DN (area under the curve=0.936; 95% confidence interval: 0.88–0.98). Conclusion Serum suPAR is significantly associated with renal dysfunction and albuminuria in T2DM and may serve as an early biomarker for DN and renal impairment severity.