Impact of parathyroidectomy on serum FGF23 and soluble Klotho in hemodialysis patients with severe secondary hyperparathyroidism.

Context: Klotho is a transmembrane protein that functions as a coreceptor for fibroblast growth factor 23 (FGF23). Klotho is cleaved and released into the circulation; however, the main site of production, physiological role, and regulation of soluble Klotho in humans are largely unknown. Objective: The aim of this study was to determine the impact of parathyroidectomy (PTx) on serum FGF23 and soluble Klotho levels in patients with severe secondary hyperparathyroidism. Design and Setting: This was a prospective, single-arm trial conducted at Tokai University School of Medicine. Patients: Thirteen hemodialysis patients with severe secondary hyperparathyroidism who were candidates for PTx participated in the study. Interventions: All patients underwent total PTx with forearm autotransplantation. Main Outcome Measures: We evaluated changes in serum FGF23 and soluble Klotho levels for 90 days after PTx. Other biochemical parameters related to mineral and bone metabolism were also assessed. Results: At baselin...