[Epidemiology of FGF23-related hypophosophatemic diseases].

Through the studies of patients with hypophosphatemic rickets/osteomalacia, fibroblast growth factor 23(FGF23)has emerged as a humoral factor that reduces serum phosphate. Discovery of FGF23 as an essential regulator of phosphate homeostasis has markedly improved our understanding of phosphate homeostasis and hypophosphatemic or hyperphosphatemic disorders. A nationwide epidemiologic survey of FGF23-related hypophosphatemic diseases indicated that the patients showed FGF23 levels of above 30 pg/mL by intact assay in the presence of hypophosphatemia. The survey also showed that prevalence and biochemical data before and after treatment of the diseases. Novel therapeutic methods for these disorders may be developed by elucidation of the mechanism of action of FGF23.