Send to:

Choose Destination
See comment in PubMed Commons below
Surgery. 1998 Dec;124(6):1021-6; discussion 1026-7.

Secondary hyperparathyroidism is an expected consequence of parathyroidectomy for primary hyperparathyroidism: a prospective study.

Author information

  • 1Department of Surgery, Johns Hopkins Hospital, Baltimore, Md. 21287, USA.



Parathyroidectomy for primary hyperparathyroidism (PHPT) can cause secondary hyperparathyroidism, with increased serum parathyroid hormone (PTH) and normal or low serum calcium concentrations.


A prospective study investigated 78 consecutive patients who underwent exploration for PHPT. Serum intact PTH and total calcium concentrations were measured the evening after operation and ionized Ca++ the following morning. These levels were reassayed 1 week later.


Before operation, the mean PTH level was 138 +/- 15 pg/mL, total calcium concentration was 11.6 +/- 0.1 mg/dL, and ionized Ca++ concentration was 1.44 +/- 0.02 mmol/L. On the night of the operation, the PTH level was 11 +/- 2 pg/mL, and the total calcium concentration was 8.9 +/- 0.1 mg/dL. Fifty-five patients had hypoparathyroidism, with a PTH level less than 10 pg/mL. The day after the operation, the ionized Ca++ level was 1.14 +/- 0.01 mmol/L. One week later, PTH, ionized Ca++, and total serum calcium concentrations returned to normal levels. In 9 patients (12%), PTH levels were increased (98 +/- 16 pg/mL), although ionized Ca++ concentrations were normal (1.18 +/- 0.02 mmol/L), demonstrating secondary hyperparathyroidism. Risk factors for postoperative secondary hyperparathyroidism included older age, symptomatic hyperparathyroidism, higher preoperative PTH and alakaline phosphatase levels, and lower serum phosphorous levels. In 70% of these patients, PTH levels returned to normal in 3 to 12 months.


Secondary hyperparathyroidism occurs in 12% of patients after surgical treatment of PHPT. It is transient, possibly compensating for relative hypocalcemia.

[PubMed - indexed for MEDLINE]
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science
    Loading ...
    Write to the Help Desk