Renal Function Assessment: Core Responsibilities of Clinical Pathologists and Laboratory Technicians in Diagnostic Evaluation

Background: The kidneys play a vital role in maintaining homeostasis by filtering metabolic waste, regulating electrolytes, and producing hormones. Chronic kidney disease (CKD) affects approximately 14% of the population, with hypertension and diabetes being leading causes. Accurate renal function assessment is crucial for early detection, disease monitoring, and treatment planning. Aim: This article reviews the core responsibilities of clinical pathologists and laboratory technicians in evaluating renal function, focusing on diagnostic tests, methodologies, and emerging biomarkers. Methodology: The study examines various renal function tests, including glomerular filtration rate (GFR) estimation (using creatinine, cystatin C, and equations like CKD-EPI), blood urea nitrogen (BUN), albuminuria, and tubular function tests. It also discusses specimen collection, interfering factors, and novel biomarkers. Results: Serum creatinine remains the most common marker for GFR estimation, though it has limitations, including delayed detection of early kidney injury. Cystatin C offers improved accuracy, particularly in patients with abnormal muscle mass. Albuminuria is a key indicator of glomerular damage, while tubular function tests help diagnose specific renal disorders. Novel biomarkers like neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule-1 (KIM-1) show promise in early AKI detection. Conclusion: Renal function tests are essential for diagnosing and managing kidney disease. While traditional markers like creatinine and BUN remain widely used, newer biomarkers and advanced equations enhance diagnostic precision. Clinical pathologists and laboratory technicians play a critical role in ensuring accurate testing and interpretation.