Estimation of KIM-1 in Patients with Chronic Kidney Disease

Abstract

Background: Chronic kidney disease (CKD) is a progressive condition with a high morbidity and mortality rate, frequently associated with hypertension and diabetes. Early detection is critical to management. Kidney Injury Molecule-1 (KIM-1) has emerged as a potential biomarker for proximal tubular injury, with higher diagnostic value than conventional markers.

Methods: A case-control study involving 90 people aged 30-70 years was conducted. It included 60 CKD patients (30 on dialysis and 30 pre-dialysis) and 30 age- and gender-matched healthy controls. Venous blood samples were collected to measure serum KIM-1 levels using an ELISA assay, as well as serum creatinine and the estimated glomerular filtration rate (eGFR).

Results: Serum KIM-1 levels were not significantly elevated in pre-dialysis CKD patients compared to healthy controls (AUC = 0.489, p = 0.897), indicating poor diagnostic performance in early CKD. However, levels were significantly higher in dialysis patients (p = 0.001). KIM-1 correlated positively with serum creatinine and negatively with eGFR (p < 0.001), with an AUC of 0.75 and sensitivities of 79%. Levels increased progressively across CKD stages. Smokers showed elevated KIM-1, while no significant differences were observed by age, gender, or comorbidities.

Conclusions: Elevated KIM-1 levels in advanced CKD suggest that the protein may serve as a disease progression marker. However, its limited sensitivity in the early stages suggests that more research is required to determine its full diagnostic utility.