Introduction: Diabetic nephropathy (DN) is a multifactorial disease, one of the most common complications of diabetes and a major cause of chronic kidney disease. Kidney injury molecule-1 (KIM-1) is a sensitive and specific marker of kidney injury as well as a predictor of prognosis.
Objective: The present study aimed to investigate the usefulness of serum KIM-1 as an early marker of DN.
Patients and methods: The present study included total 75 participants, among whom 25 nondiabetic participants were chosen as controls. The 50 diabetic participants were divided into two groups according to urine protein/creatinine ratio (UPCR) as participants with normoalbuminuria (T2DM patients without nephropathy) and microalbuminuria (T2DM patients with nephropathy). The complete blood count, blood glucose, HbA1c, serum electrolytes, and creatinine levels were measured using standard laboratory techniques, and serum KIM-1 levels were measured by sandwich enzyme-linked immunosorbent assay.
Results: There was a significant difference in the mean serum KIM-1 between the control and diabetics without microalbuminuria (P = 0.0001). Patients with longer duration of diabetes had a higher serum KIM-1 values (P = 0.05 in DM without microalbuminuria; P = 0.007 for DM with microalbuminuria). Serum KIM-1 did not correlate with UPCR in controls (P = ‒0.167), in diabetics with microalbuminuria (P = 0.487). However, there was a significant correlation observed between UPCR and serum KIM-1 in diabetics without microalbuminuria (P = 0.04).
Conclusion: The present study observed significantly increased levels of serum KIM-1 in both the diabetic groups compared to controls. Moreover, serum KIM-1 positively correlated with the duration of diabetes. Therefore, serum KIM-1 may be used as an early diagnostic marker to predict nephropathy among diabetes in our population.
Keywords: Diabetes mellitus; diabetic nephropathy; kidney injury molecule-1; microalbuminuria; urine protein/creatinine ratio.