Measurement of intraoperative parathyroid hormone predicts long-term operative success.

HYPOTHESIS: A decrease in the intraoperative parathyroid hormone (PTH) level predicts long-term operative success. DESIGN: A case series of consecutive patients undergoing parathyroidectomy with intraoperative PTH measurement. SETTING: A university hospital. PATIENTS AND INTERVENTION: One hundred two patients with sporadic primary hyperparathyroidism underwent parathyroidectomy according to the principles of unilateral exploration with intraoperative PTH measurement. MAIN OUTCOME MEASURES: Longitudinal effects on levels of serum calcium and PTH. RESULTS: In 94 of 98 patients who underwent primary exploration because of a solitary adenoma, intraoperative PTH decreased at least 60% 15 minutes after gland excision. The 4 cases in which PTH fell to less than 60% were classified as false negatives. Patients examined for multiglandular disease (n = 4) were correctly predicted not to have an adenoma. Twenty-two patients (22%) were unavailable for 5-year follow-up. These patients were followed up for 2 months to 48 months (median, 24 months), and none developed recurrent primary hyperparathyroidism. Of the remaining 80 patients (78%), all but 1 patient had normal or slightly decreased serum calcium levels (mean +/- SD, 9.24 +/- 0.4 mg/dL [2.31 +/- 0.10 mmol/L]) at 5-year follow-up. One patient with hypercalcemia (10.6 mg/dL [2.65 mmol/L]) was interpreted to have developed renal failure with secondary hyperparathyroidism. Thirty-four patients had elevated serum PTH levels at least once during the postoperative study period, with normal or slightly decreased calcium concentrations. The prediction of late postoperative normocalcemia by means of intraoperative PTH measurement had an overall accuracy of 95%. CONCLUSIONS: The measurement of intraoperative PTH during surgery for primary hyperparathyroidism accurately differentiates between single- and multiple-gland disease and ensures good long-term results.