EVALUATING URINARY HAPTOGLOBULIN AS A BIOMARKER FOR EARLY RENAL FUNCTION DECLINE IN T2DM

Background and Aims: Diabetic nephropathy (DN) affect a significant proportion of diabetes mellitus (T2DM) patients. Microalbuminuria, an early marker of diabetic kidney disease (DKD), has limited sensitivity and specificity, particularly in normoalbuminuric patients, where 38-73% with chronic kidney disease (CKD) lack microalbuminuria. Urinary haptoglobin (uHp) and its ratio with creatinine (uHCR) are emerging biomarkers for early detection of renal dysfunction. This study evaluates the diagnostic utility of uHCR in detecting and predicting renal function decline in T2DM. Methods: This prospective analytical study was conducted at F.H. Medical College, Agra, India, with Ethical Committee approval and informed consent. T2DM patients meeting inclusion criteria were included. Patients were prescribed oral hypoglycemic agents and RAAS inhibitors as required. Measurements included serum creatinine, urinary albumin, urinary creatinine, and urinary haptoglobin. Statistical analysis compared uHCR with traditional biomarkers. Results: uHCR demonstrated improved specificity over spot uHp and was comparable to uACR in predicting nephropathy in patients with both deranged and preserved renal function. uHCR persisted longer than uACR posttreatment, indicating its role in detecting residual renal dysfunction. Elevated uHCR in normoalbuminuric T2DM patients suggested its potential to predict nephropathy earlier than microalbuminuria. Conclusion: Urinary haptoglobin and uHCR are promising tools for early detection and monitoring of DN. Preliminary findings suggest that uHCR could augment or replace uACR in predicting DN. Larger studies are needed to validate their predictive thresholds, refine accuracy, and assess confounding factors