Novel criteria for parathyroid hormone levels in parathyroid hormone-guided parathyroid surgery.

CONTEXT: Novel criteria for decrease of perioperative parathyroid hormone measurement may improve the accuracy of perioperative quick parathyroid hormone (qPTH)-guided parathyroidectomy. OBJECTIVE: To assess overall cure rate based on conventional criteria (50% decline of qPTH). Perioperative qPTH levels were evaluated to determine novel criteria for successful parathyroid surgery. DESIGN: Analysis of perioperative qPTH measurement findings of all consecutive patients undergoing parathyroidectomy for hyperparathyroidism (72 with primary hyperparathyroidism and 28 with secondary or tertiary hyperparathyroidism or multiple endocrine neoplasia I/IIa disease). RESULTS: Measurement of qPTH (based solely on the criterion of greater than 50% decline of parathyroid hormone) in 72 patients with primary hyperparathyroidism (77 procedures) showed true-positive results in 69, false-positive results in 4, and true-negative results in 4 procedures. In our series, false-positive and true-negative results were associated with high postexcision levels. However, when qPTH declines of greater than 70% and 80% were used in cases of postexcision qPTH levels of 100 to 200 ng/L and greater than 200 ng/L, respectively, no false-positive results were observed. CONCLUSIONS: Through adherence to these novel criteria, reexploration of the neck could have been prevented in 29% of patients with primary hyperparathyroidism due to multiple gland disease. These novel criteria demand future evaluation to establish their value.