INTRODUCTION

Primary hyperparathyroidism (PHPT) is often recognized as a result of biochemical screening or as part of an evaluation for decreased bone mass. Most of the patients have serum calcium concentrations of 11.5 mg/dL (2.9 mmol/L) or less. Among such patients, the majority are women over age 50 years, and most have few if any symptoms, although the distinction between asymptomatic and symptomatic PHPT is not always clear-cut. Patients may deny symptoms, whereas a family member may say the patient has been mildly symptomatic in some way [1-3]. (See "Clinical manifestations of primary hyperparathyroidism" and "Diagnosis and differential diagnosis of primary hyperparathyroidism".)

Although patients with symptomatic primary hyperparathyroidism should have parathyroid surgery, the widespread identification of asymptomatic individuals raises the question of if, and when, these individuals should undergo surgery [4,5]. Although most asymptomatic patients do not have progression of disease, as defined by worsening hypercalcemia, hypercalciuria, bone disease, and/or nephrolithiasis, some individuals do progress and would benefit from surgical cure. Thus, the primary goal is to identify the asymptomatic individuals at risk for disease progression, as well as those who have features of the disease that may improve following parathyroidectomy. These two groups of individuals would likely benefit from surgical intervention.

This topic reviews how to identify these individuals and the risks and benefits of medical versus surgical management in this population. Diagnostic localization of a parathyroid adenoma and the method of surgical removal are discussed in greater detail elsewhere. (See "Preoperative localization for parathyroid surgery" and "Surgical therapy of primary hyperparathyroidism".)

The decision regarding medical versus surgical treatment does not apply to patients who have familial hypocalciuric hypercalcemia. Patients with this disorder have mild hypercalcemia, few if any symptoms, no evidence of end organ damage from their disease, and no benefit from parathyroidectomy. (See "Disorders of the calcium-sensing receptor: Familial hypocalciuric hypercalcemia and autosomal dominant hypocalcemia".)

SURGERY VERSUS MEDICAL MANAGEMENT

Patients with symptomatic primary hyperparathyroidism should have parathyroid surgery. However, many patients with hyperparathyroidism are asymptomatic or have subclinical symptoms or nonclassical manifestations of their disease. Parathyroidectomy is an effective therapy that cures the disease, decreases the risk of kidney stones, improves bone mineral density and may decrease fracture risk and modestly improve some quality of life measurements. In addition, proponents of surgery for asymptomatic individuals argue that many untreated patients are lost to follow-up after 5 to 10 years and that the cost of follow-up visits and tests may ultimately exceed the costs of surgery [6,7]. Thus, some argue that parathyroidectomy is an attractive strategy for nearly all patients [8].