TY - JOUR
T1 - Secondary hyperparathyroidism is an expected consequence of parathyroidectomy for primary hyperparathyroidism
T2 - A prospective study
AU - Mandal, A. K.
AU - Udelsman, R.
AU - Henry, J. F.
AU - Inabnet, W. B.
AU - Carty, S. E.
PY - 1998
Y1 - 1998
N2 - Background. Parathyroidectomy for primary hyperparathyroidism (PHPT) can cause secondary hyperparathyroidism, with increased serum parathyroid hormone (PTH) and normal or low serum calcium concentrations. Methods. 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. Results. 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 alkaline phosphatase levels, and lower serum phosphorous levels. In 70% of these patients, PTH levels returned to normal in 3 to 12 months. Conclusions. Secondary hyperparathyroidism occurs in 12% of patients after surgical treatment of PHPT. It is transient, possibly compensating for relative hypocalcemia.
AB - Background. Parathyroidectomy for primary hyperparathyroidism (PHPT) can cause secondary hyperparathyroidism, with increased serum parathyroid hormone (PTH) and normal or low serum calcium concentrations. Methods. 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. Results. 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 alkaline phosphatase levels, and lower serum phosphorous levels. In 70% of these patients, PTH levels returned to normal in 3 to 12 months. Conclusions. Secondary hyperparathyroidism occurs in 12% of patients after surgical treatment of PHPT. It is transient, possibly compensating for relative hypocalcemia.
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U2 - 10.1067/msy.1998.92004
DO - 10.1067/msy.1998.92004
M3 - Article
C2 - 9854578
AN - SCOPUS:0031731644
SN - 0039-6060
VL - 124
SP - 1021
EP - 1027
JO - Surgery
JF - Surgery
IS - 6
ER -