Elevated FGF-23 in a patient with rhabdomyolysis-induced acute kidney injury

Rhabdomyolysis-induced acute kidney injury (AKI) is characterized by hyperphosphataemia and hypocalcaemia. Despite appropriate secondary elevation of parathyroid hormone (PTH) in response to hypocalcaemia, rhabdo-myolysis and AKI are associated with acute deficiency of 1,25-dihydroxycholecalciferol (1,25(OH)(2)D-3), and yet, the mechanism responsible for such a deficiency remains unclear. Fibroblast growth factor 23 (FGF-23), a potent phosphaturic hormone that inhibits 25-hydroxyvitamin D-3-1 alpha-hydroxylase, could explain the deficiency of 1,25 (OH)(2)D-3 in this setting. Here, we document, for the first time, elevated levels of FGF-23 in a patient with rhabdomyolysis-induced AKI.