Monika Chhillar, Poornima Bhatt
Chronic Kidney Disease (CKD) is a global public health crisis, affecting over 800 million people worldwide. Driven primarily by diabetes and hypertension, it causes substantial morbidity and premature mortality while placing massive economic and environmental demands on global healthcare systems. CKD often gets diagnosed at later stages due to inadequate sensitivity of current CKD biomarkers, such as serum CR and blood urea nitrogen. It is vital to diagnose the condition earlier in order to prevent its complications. This review offers an extensive review of CKD pathophysiology and consequences, paying special attention to the role played by inflammation, oxidative stress, and fibrosis. This review presents CKD biomarkers in accordance with their functions and discusses their advantages and disadvantages. Functional, damage, filter, inflammation, fibrosis, oxidative stress, and omics biomarkers are classified. Moreover, there is information about newly emerged biomarkers like neutrophil gelatinase-associated lipocalin, kidney injury molecule-1, and cystatin C. Also, different types of diagnostic and sensing methodologies are reviewed, ranging from standard laboratory techniques to innovative technologies, which include electrochemical sensors, optical biosensors, and affinity biosensors, as well as integrated sensing platforms such as point-of-care testing devices and microfluidic devices. The comparative analysis of biomarkers and the detection technique is provided for their clinical applicability. Lastly, future directions and challenges in the area of CKD biomarkers and detection, such as multiplex detection of biomarkers, artificial intelligence-integrated detection systems, and personalized diagnostics, are emphasized.