However, the potential role of FGF23, Klotho, and Sclerostin in nephrolithiasis is still poorly under-stood or even unexplored. The aim of this study is to test if levels of FGF23, Klotho, and Sclerostin are differentially regulated in kidney stone formers. Given the large number of kidney stone patients worldwide, the better understanding of the pathogenesis of kidney disease may provide the basis for the design of more individualized and specifically targeted therapeutics for this patient cohort.