Nonoperative management of hyperparathyroidism: present and future.

Parathyroidectomy provides effective treatment for primary and secondary hyperparathyroidism with a predictable response of symptoms related to hypercalcemia and elevated parathyroid hormone. Calcium and vitamin D supplementation has reduced the need for parathyroidectomy in dialysis patients with secondary hyperparathyroidism. However, surgery continues to be the only effective treatment of primary hyperparathyroidism. Potential nonoperative treatments for hyperparathyroidism have included the use of estrogen replacement, bisphosphonates, and a new class of drugs known as calcimimetics. Hormone replacement therapy with estrogen has been reported to improve cortical bone density in postmenopausal women with asymptomatic or mildly symptomatic primary hyperparathyroidism. Calcimimetic agents are a new class of drugs that increase the sensitivity of the calcium receptor to ionized calcium. Initial studies have shown that calcimimetics can acutely lower parathyroid hormone levels in patients with primary and secondary hyperparathyroidism. These drugs are currently being evaluated in phase II clinical trials. Ultimately, these medical modalities will need to be compared to parathyroidectomy in randomized controlled clinical trials.