Fibroblast growth factor 23, parathyroid hormone, and 1alpha,25-dihydroxyvitamin D in surgically treated primary hyperparathyroidism.
OBJECTIVE
To determine whether fibroblast growth factor 23 (FGF23) contributes to the hypophosphatemia of primary hyperparathyroldism.


METHODS
Thirteen adult patients with primary hyperparathyroidism had serum collected before and after parathyroidectomy for analysis of inorganic phosphorus, calcium, 1alpha,25-dihydroxyvitamin D (1alpha,25[OH]2D), parathyroid hormone (PTH), FGF23, creatinine, and bone-specific alkaline phosphatase (BSAP). Patients were recruited between July 24, 2003, and February 11, 2004.


RESULTS
Before surgery, patients had elevated serum calcium and PTH concentrations. Serum phosphorus concentrations were in the low-normal range. The FGF23 concentrations were not elevated in patients with primary hyperparathyroidism compared with healthy controls. Within 24 hours of surgery, serum calcium, PTH, 1alpha,25(OH)2D, and BSAP concentrations were lower (P < .002 for all) and phosphorus concentrations were higher (P = .003) than in the preoperative state. The FGF23 concentrations were similar 1 day and 6 weeks after surgery. The FGF23 concentrations did not correlate with serum phosphorus, calcium, PTH, 1alpha,25(OH)2D, creatinine, or BSAP concentrations in the preoperative or postoperative state.


CONCLUSIONS
Parathyroid hormone is the major regulator of serum phosphorus concentrations in patients with primary hyperparathyroidism. Fibroblast growth factor 23 does not appear to play a role in phosphorus homeostasis in patients with surgically treated primary hyperparathyroidism.
Tebben
Peter J
PJ
Division of Endocrinology, Diabetes, Metabolism, and Nutrition and Internal Medicine, Mayo Clinic College of Medicine, Rochester, Minn 55905, USA.
Singh
Ravinder J
RJ
Clarke
Bart L
BL
Kumar
Rajiv
R
D000328:Adult; D000368:Aged; D015415:Biomarkers; D004100:Dihydroxycholecalciferols / Q000032:analysis / Q000097:blood*; D005260:Female; D000089703:Fibroblast Growth Factor-23; D005346:Fibroblast Growth Factors / Q000032:analysis / Q000097:blood*; D005500:Follow-Up Studies; D006801:Humans; D006961:Hyperparathyroidism / Q000097:blood* / Q000175:diagnosis / Q000601:surgery; D008297:Male; D008875:Middle Aged; D010280:Parathyroid Glands / Q000473:pathology / Q000601:surgery*; D010281:Parathyroid Hormone / Q000032:analysis / Q000097:blood*; D016105:Parathyroidectomy; D011182:Postoperative Care; D011300:Preoperative Care; D011336:Probability; D011446:Prospective Studies; D012494:Sampling Studies; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D018709:Statistics, Nonparametric; D016896:Treatment Outcome
D015415:Biomarkers; D004100:Dihydroxycholecalciferols; C000717427:FGF23 protein, human; D010281:Parathyroid Hormone; D005346:Fibroblast Growth Factors; D000089703:Fibroblast Growth Factor-23