Biomarkers and kidney diseases: a brief narrative review

Background and Objective: Current biomolecular identification techniques expose new aspects in the biological universe of the human body. Omics strategies through genomics, metabolomics, lipidomics and proteomics generate thousands of information that demand math resources to integrate the meanings of multiple molecular patterns in the construction of modern biochemical knowledge of the interior environment. Biomarkers are endogenous molecules, detected qualitatively and/or quantitatively, which provide peculiar data for the identification of physiological or pathophysiological processes, as well as for the control of pharmacological responses. This narrative literature review aims to provide an update on biomarkers of kidney diseases. Methods: We searched the PubMed database for clinical trial articles published in English, in the timeline from January 1990 to December 2021, with the following search terms: "AKI Biomarkers", "Podocytopathy Biomarkers", "Lupus Kidney Biomarkers", "Diabetic Glomerulopathy Biomarkers", "Diabetic Nephropathy Biomarkers", "Tubular Renal Biomarkers" and "Renal Biomarkers". Key Content and Findings: Excluding 9 cross -responses and 1 veterinary study, 224 publications were selected, 77% of which have been published since 2010. We designed this narrative review primarily on the basis of this set of manuscripts. Conclusions: Kidney biomarkers can be classified according to the morphophysiological characteristics of the nephron, regarding both the renal function (glomerular and tubular) and tissue integrity of its endothelial or epithelial cells. The development of these biomarkers is not focused on the identification of a specific disease, but on the detection of a renal pathophysiological phenomenon, with variable complexities and etiologies. This new molecular panel could be very useful for nephrologists in helping to make clinical decisions.