CYSTATIN C AS AN EARLY MARKER OF RENAL DYSFUNCTION IN PATIENTS WITH CHRONIC KIDNEY DISEASE STAGES 1–2

Abstract

Chronic kidney disease (CKD) is a prevalent condition characterized by an asymptomatic early course and a high risk of cardiovascular complications. Early detection remains challenging, as traditional markers such as serum creatinine have limited sensitivity in the initial stages. This study aimed to evaluate the clinical and laboratory characteristics of patients with CKD stages 1–2 and to assess the diagnostic value of cystatin C as an early biomarker of renal dysfunction. A total of 88 patients were divided into stage 1 (n = 53) and stage 2 (n = 35) groups. Comprehensive clinical and laboratory assessments were performed. Patients with CKD stage 2 were older and had a longer disease duration. While creatinine levels were moderately elevated, the most significant differences were observed in cystatin C levels (p < 0.001). ROC analysis demonstrated high diagnostic accuracy of cystatin C (AUC = 0.89), with a cut-off value of ≥18.0 mg/L providing 84.6% sensitivity and 81.1% specificity. Cystatin C is a sensitive and specific marker for early renal dysfunction and may improve early diagnosis and management of CKD