SOST and Renal insufficiency: A positive correlation of Sclerostin with FGF23 has been already described in conservative renal insufficiency [10,11,16] and is confirmatory of the experimental evidence suggesting that Sclerostin increases FGF23 by inhibiting PHEX (a protein encoded by the Phosphate regulating gene with Homologies to Endopeptidases on the X chromosome) [7].