Medical Management of Primary Hyperparathyroidism

Primary hyperparathyroidism (PHPT) is the most common cause of hypercalcemia in the outpatient population. It is diagnosed in most individuals in the Western world at an asymptomatic stage without signs or symptoms of parathyroid hormone (PTH) calcium excess. Nonspecific symptoms include weakness, malaise, fatigue, and possible mood disturbances, which may be present at the time of diagnosis. The diagnosis of PHPT is confirmed in the presence of hypercalcemia and a normal or elevated PTH level in the absence of conditions that mimic PHPT. Indications for surgery have recently been revised based on international consensus, and surgery is advised in the presence of significant hypercalcemia, impaired renal function, and osteoporosis and in individuals younger than 50yr. The classical complications of PHPT are skeletal fragility, nephrolithiasis, and nephrocalcinosis. Surgery is always appropriate in an individual with confirmed PHPT after excluding conditions that can mimic PHPT and in the absence of contraindications. Individuals with asymptomatic PHPT not meeting the guidelines for surgery or those with contraindications for surgery may be followed and considered for medical management. For those at an increased risk of fragility fracture, antiresorptive therapy may be considered with close monitoring of biochemical data and bone densitometry. Targeted therapy with a calcimimetic agent may be of value in lowering serum calcium and PTH. There are currently no fracture data for the medical options available, and prospective randomized controlled trials are required to confirm the effects of medical therapy on fracture risk reduction in those with asymptomatic PHPT.