Current status and treatment of primary hyperparathyroidism.

Primary hyperparathyroidism (HPT) is diagnosed in approximately 100,000 patients in the US each year, with a 2-3:1 female-to-male distribution. In most cases, occurrence is sporadic rather than familial, and 80% to 85% of cases of sporadic primary HPT are caused by a solitary parathyroid adenoma. The diagnosis is made by hypercalcemia with an inappropriately elevated parathyroid hormone (PTH) level and a 24-hour urine calcium excretion level that is normal or high. Truly asymptomatic primary HPT is rare, as most patients have symptoms or metabolic complications when carefully evaluated by standardized health questionnaires. The National Institutes of Health (NIH) published guidelines in 2002, recommending parathyroidectomy for all symptomatic patients and for asymptomatic patients less than age 50 years or those who cannot participate in medical surveillance. These criteria have been called into question as being too limited, because multiple studies have demonstrated symptomatic and metabolic benefits of parathyroidectomy in "asymptomatic" patients. Given the studies showing an improvement in quality-of-life measures, future risk for developing renal calculi, bone density, cardiovascular health, and risk of death, we believe that virtually all patients with primary HPT should undergo surgical resection. An improvement in preoperative localization studies as well as the development of a rapid intraoperative PTH assay has changed the approach to parathyroid surgery since the 1980s. Because most sporadic primary HPT is caused by a single gland adenoma, our preferred procedure has now changed from a bilateral neck exploration to a focused or unilateral approach, with similar rates of success in patients with a solitary tumor identified preoperatively.