FGF23 and chronic kidney disease: In the present study, we found that in the early stages of CKD (mean eGFR of 83.69 ± 17.37 mL/min/1.73 m2), serum phosphorous and PTH were in the normal range even with increasing serum levels of FGF-23 [19] and these findings are supported by the Chronic Renal Insufficiency Cohort study (2011) by Isakova et al. [20].