Novel molecular biomarkers in kidney diseases: bridging the gap between early detection and clinical implementation.

Background: Kidney diseases affect over 850 million people globally and are a significant cause of morbidity and mortality. Traditional biomarkers like serum creatinine, blood urea nitrogen, and proteinuria have limited sensitivity and specificity, often detecting damage only after substantial renal function loss. Even U.S. Food and Drug Administration (FDA)-approved biomarkers, such as kidney injury molecule-1, neutrophil gelatinase-associated lipocalin, and cystatin C, have limitations because their levels can be influenced by inflammation, infections, or disease stage. There is an urgent need for reliable, non-invasive biomarkers for early diagnosis and treatment guidance.

Objective: This review provides an updated overview of emerging biomarkers for early detection and monitoring of kidney diseases (acute kidney injury, chronic kidney disease, diabetic kidney disease, polycystic kidney disease, lupus nephritis, renal cell carcinoma).

Methods: A comprehensive literature review focused on studies from the past decade on urine and blood-based biomarkers that reflect key pathological processes, including inflammation, tubular injury, fibrosis, and immune activation.

Results: Promising biomarkers include collectrin, olfactomedin 4, activin A, follistatin, USP18, galectin-3, fetuin-A, sestrin-2, podocalyxin, copeptin, anti-C1q, p-cresol glucuronide, serum CD206, lncRNAs, and miRNAs.

Conclusions: These biomarkers may enhance early diagnosis, enable personalized therapy, and improve kidney disease outcomes. Their integration into clinical practice may bridge the gap between early detection and effective intervention, potentially improving long-term outcomes in patients with kidney disease.