Endocrine Connections (Feb 2022)

Perioperative changes of FGF23 in patients undergoing surgery for primary hyperparathyroidism

  • Magdaléna Fořtová,
  • Lenka Hanousková,
  • Martin Valkus,
  • Jana Čepová,
  • Richard Průša,
  • Karel Kotaška

DOI
https://doi.org/10.1530/EC-21-0430
Journal volume & issue
Vol. 11, no. 1
pp. 1 – 8

Abstract

Read online

Background: Fibroblast growth factor 23 (FGF23) is a key regulator of urine phosphate excretion. The aim of the study was to investigate the perioperative (intraoperative and postoperative) changes of plasma intact and C-terminal FGF23 (iFGF23, cFGF23) concentrations in patients with primary hyperparathyroidism (pHPT) submitted to surgery. Materials and methods: The study involved 38 adult patients with pHPT caused by adenoma. Parathyroid hormone (PTH) levels were investigated intraoperatively (just before the incision and 10 min after adenoma excision). cFGF23, iFGF23, phosphate, estimated glomerular filtration rate (eGFR), and procollagen typ e 1 N-terminal propetide (P1NP) were measured intraoperatively and postoperatively (next day after the surgery). Results: PTH levels decreased intraoperatively (13.10 pmol/L vs 4.17 pmol/L, P < 0.0001). FGF23 levels measured intraoperatively were at the upper level of reference interval. cFGF23 decreased postoperatively compared with the values measured just before the incision (cFGF23: 89.17 RU/mL vs 22.23 RU/mL, P < 0.0001). iFGF23 decreased as well, but the postoperative values were low. Postoperative inorganic phosphate values increased (1.03 mmol/L vs 0.8 mmol/L, P = 0.0025). We proved significant negative correlation of perioperative FGF23 with inorganic phosphate (cFGF23: Spearm an’s r = −0.253, P = 0.0065; iFGF23: Spearman’s r = −0.245, P = 0.0085). We also found that FGF23 values just before incision correlated with eGFR (cystatin C) (cFGF23: Spearman’s r = −0.499, P = 0.0014; iFGF23: Spearman’s r = −0.413, P = 0.01). Conclusion: Intraoperative iFGF23 and cFGF23 did not change despite PTH decreased significantly. cFGF23 and iFGF23 significantly decreased 1 day af ter parathyroidectomy and are associated with increase of inorganic phosphate in pHPT patients. cFGF23 and iFGF23 just before incision correlated with eGFR (cystatin C). Similar results found in both iFGF23 and cFGF23 suggest that each could substitute the other.

Keywords