Research overview: FGF23 and mineral bone disorder in feline CKD

Fibroblast growth factor 23 (FGF23), a hormone regulating phosphate, rises early in feline CKD as the kidneys struggle to excrete phosphorus, and elevated levels have been associated with disease progression and worse outcomes. Studying FGF23 alongside parathyroid hormone and vitamin D has clarified the renal mineral and bone disorder that accompanies declining kidney function. This overview compiles the endocrine and nephrology literature rather than one source, describing how FGF23 reflects phosphate stress before overt hyperphosphatemia, why it may serve as a prognostic marker and a rationale for early phosphorus control, and how understanding mineral dysregulation refines management. It matters because FGF23 links the biochemistry of phosphorus handling to the clinical strategy of restricting phosphorus to slow CKD progression.