FGF23 and chronic kidney disease: Serum Fibroblast Growth Factor-23 (FGF-23) a phosphaturic hormone secreted by osteoblasts, inhibits 1 alpha hydroxylase enzyme, preventing conversion of 25 (OH)D to 1,25 dihydroxy vitamin D [1,25 (OH)2D] is elevated in CKD, and associated with mortality, coronary artery atherosclerosis and left ventricular hypertrophy [19]–[21].