Management of Primary Hyperparathyroidism: Historical and Contemporary Perspectives.

Primary hyperparathyroidism (PHPT) is a frequently diagnosed endocrine condition most commonly caused by a single parathyroid adenoma. Our understanding of the epidemiology and management of PHPT have evolved in the past few decades. Asymptomatic PHPT has been the most common presentation in developed countries since the advent of routine biochemical screening. Symptomatic disease is now also decreasing in developing nations. Normocalcemic PHPT is a newer phenotype that can be diagnosed in the setting of elevated parathyroid hormone concentrations with persistently normal serum calcium; however, evaluation for secondary causes of hyperparathyroidism is critical as it is a diagnosis of exclusion. Genetic testing can be helpful in patients younger than 30 years of age and/or patients with intermediate or equivocal ranges of the urinary calcium to creatinine ratio (between 0.01 and 0.02) to differentiate PHPT from familial hypocalciuric hypercalcemia and to evaluate for other genetic etiologies that may affect management. Surgery is the recommended treatment modality for symptomatic PHPT, and patients with asymptomatic PHPT meeting recommended criteria should also be considered for parathyroidectomy. "Asymptomatic" patients should be screened for the presence of nephrolithiasis and/or vertebral fracture, since many will be reclassified as having symptomatic disease with further investigation. For poor surgical candidates or patients not meeting criteria for surgery, medical therapy includes cinacalcet for hypercalcemia and antiresorptive therapies for osteoporosis.