Is there a role for newer biomarkers in chronic kidney disease‐mineral and bone disorder management?

Abstract

ABSTRACT:The current management of Chronic Kidney Disease-Mineral Bone Disorder (CKD-MBD) relies largely on clinical judgement and assessment of biochemical parameters including serum calcium, phosphate and intact parathyroid hormone concentrations. In the past two decades, there has been a leap in the understanding of the pathophysiology of CKD-MBD, leading to the discovery of novel biomarkers. The potential utility of these markers in this clinical setting is an area of intense investigation. In the absence of any guidelines aiding the clinician's understanding and application of these markers, we summarise the current available literature surrounding fibroblast growth factor-23, α-Klotho, sclerostin and serum calcification propensity testing and their respective assays in the context of CKD-MBD management.

The role of klotho in chronic kidney disease

“…Although the results of relations between circulating klotho levels and outcomes of CKD are contradictory, three commonly used commercial immunoassay products for measuring soluble klotho-- are available from IBL (IBL International GmbH, Hamburg, Germany), Cusabio (Cusabio Biotech, Wuhan, China), and USCN (USCN Life Science Inc., Wuhan, China) [ 159 ]. Only the IBL kit provides information on epitope specificity [ 159 ].…”

“…Although the results of relations between circulating klotho levels and outcomes of CKD are contradictory, three commonly used commercial immunoassay products for measuring soluble klotho-- are available from IBL (IBL International GmbH, Hamburg, Germany), Cusabio (Cusabio Biotech, Wuhan, China), and USCN (USCN Life Science Inc., Wuhan, China) [ 159 ]. Only the IBL kit provides information on epitope specificity [ 159 ]. However, researchers have found that these assays exhibited poor performance, including a lack of unit standardization in readouts, and the assays have to be improved to produce accurate results before they can provide reliable conclusions [ 160 ].…”

Osteopontin Levels in Patients With Chronic Kidney Disease Stage 5 on Hemodialysis Directly Correlate With Intact Parathyroid Hormone and Alkaline Phosphatase

“…3,4 Therefore, the utility in identifying additional biomarkers to better evaluate, diagnose, and treat patients with CKD5-HD with MBD is appealing. [8][9][10][11] Osteopontin (OPN) is a glycol-phosphoprotein found in bone, acute and chronic inflammatory cells, smooth muscle, epithelial, and endothelial cells, neurons, and fetal renal tissue and is expressed in the thick ascending limb of the loop of Henle. 12,13 Some of its functions include increasing macrophage and T-cell counts, perpetuation of inflammation, wound healing, tumor development and progression, roles in diabetes, and possible roles in the regulation of nephrolithiasis and nephrogenesis.…”

“…3,4 Therefore, the utility in identifying additional biomarkers to better evaluate, diagnose, and treat patients with CKD5-HD with MBD is appealing. 8 -11…”

“…A number of biomarkers have been evaluated in CKD-MBD, but there is a clear need for better characterization of novel markers, especially within the context of CKD5-HD. 9,10,11 Serum monitoring of OPN may satisfy this need for improved diagnosis and management of CKD-MBD as it (1) has clear physiologic functions associated with bone and mineral regulation and (2) has been shown to have high sensitivity and specificity in diagnosing bone turnover disease and coronary calcification in certain populations. 24,25 Our study sought to evaluate the plasma levels of OPN in a CKD5-HD population and describe its relationship to the current markers used for evaluating MBD established by the KDIGO group.…”