FGF23 and Marchiafava-Bignami disease: In addition, in patients with CKD stages 2–5, serum sclerostin was reported to be associated with inflammation markers, phosphate, FGF23, indoxylsulphate and p-cresyl sulphate, β2-microglobulin, and arterial stiffness [134], emphasizing its role in CKD-MBD development.