Surgical Management of Normocalcemic Primary Hyperparathyroidism and the Impact of Intraoperative Parathyroid Hormone Testing on Outcome

Otolaryngol Head Neck Surg. 2018 Oct;159(4):630-637. doi: 10.1177/0194599818793879. Epub 2018 Aug 14.


Objective To review our surgical experience and the impact of intraoperative parathyroid hormone (IOPTH) testing among patients with normocalcemic primary hyperparathyroidism. Study Design Case series with chart review. Setting Academic referral hospital. Subject and Methods Normocalcemic hyperparathyroidism (NCHPT) patients were identified with normal-range blood ionized calcium and serum elevated parathyroid hormone. Patient demographics, intraoperative findings, IOPTH dynamics, and biochemical outcomes were compared with those of classic primary hyperparathyroidism (PHPT) patients. Results Of the 2120 patients who underwent parathyroidectomy, 616 patients met the inclusion criteria: 119 (19.5%) patients had NCHPT, and 497 (80.5%) had classic PHPT. NCHPT patients had higher rates of multigland hyperplasia as compared with classic PHPT (12% vs 4%, P = .002) and smaller gland size ( P < .001). Of 119 NCHPT patients, 114 (97%) achieved >50% drop in IOPTH intraoperatively, as opposed to 492 (99%) among 497 classic PHPT patients ( P = .014). IOPTH drop >50% had an equivalent positive predictive value for long-term cure in both groups. Conclusions Surgeons treating NCHPT patients should suspect the presence of multigland disease and have a low threshold for converting to bilateral exploration depending on IOPTH decay dynamics.

Keywords: PTH; hyperparathyroidism; intraoperative parathyroid hormone monitoring; mild; normocalcemic; primary.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Academic Medical Centers
  • Adult
  • Age Factors
  • Aged
  • Calcium / blood*
  • Databases, Factual
  • Female
  • Follow-Up Studies
  • Humans
  • Hyperparathyroidism, Primary / blood*
  • Hyperparathyroidism, Primary / surgery*
  • Male
  • Middle Aged
  • Monitoring, Intraoperative / methods*
  • Parathyroid Hormone / blood*
  • Parathyroidectomy / adverse effects
  • Parathyroidectomy / methods*
  • Recurrence
  • Retrospective Studies
  • Risk Assessment
  • Sex Factors
  • Time Factors
  • Treatment Outcome


  • Parathyroid Hormone
  • Calcium