From the Guidelines
Hyperparathyroidism is defined as excessive parathyroid hormone (PTH) production, typically resulting in hypercalcemia, and is most commonly caused by a single parathyroid adenoma (80%). The condition can be primary, secondary, or tertiary, with primary hyperparathyroidism (PHPT) being the most common form, occurring when parathyroid glands autonomously overproduce PTH 1. PHPT is diagnosed by biochemical testing, specifically serum calcium and serum PTH, and can be asymptomatic or present with symptoms related to target organ involvement, such as bone demineralization, fractures, nephrolithiasis, and neurocognitive disorders 1.
Pathophysiology
The excess PTH produced in PHPT increases calcium absorption from the intestines, promotes calcium release from bones, and reduces calcium excretion by the kidneys, resulting in elevated blood calcium levels (hypercalcemia) 1. This can lead to a range of symptoms, including bone pain, kidney stones, abdominal discomfort, fatigue, depression, and cognitive issues.
Treatment
Treatment of PHPT typically involves surgical excision of the abnormally functioning parathyroid tissue, with two accepted curative operative strategies: bilateral neck exploration (BNE) and minimally invasive parathyroidectomy (MIP) 1. MIP is often preferred for patients with a single adenoma, as it conveys the benefits of shorter operating times, faster recovery, and decreased perioperative costs. However, BNE may be necessary in cases of discordant or nonlocalizing preoperative imaging or when there is high suspicion for multigland disease (MGD) 1.
Diagnosis and Imaging
Imaging plays a crucial role in localizing the abnormally functioning gland or glands with high accuracy and high confidence to facilitate targeted curative surgery 1. However, imaging has no utility in confirming or excluding the diagnosis of PHPT, which is typically made through biochemical testing 1. In cases of persistent or recurrent PHPT, preoperative imaging is essential to localize a target parathyroid lesion (or lesions) and to identify postoperative changes from previous parathyroid explorations that can impact a subsequent surgery 1.
From the FDA Drug Label
The FDA drug label does not answer the question.
From the Research
Hyperparathyroidism Overview
- Hyperparathyroidism is a common endocrine disorder characterized by hypercalcaemia and elevated or inappropriately normal serum levels of parathyroid hormone 2, 3.
- The disorder can manifest with osteoporosis, hypercalciuria, vertebral fractures, and nephrolithiasis, and can be asymptomatic in many cases 2, 3.
Pathogenesis and Diagnosis
- Primary hyperparathyroidism is almost always due to a benign overgrowth of parathyroid tissue, either as a single gland or as a multiple gland disorder 3.
- The disease is generally discovered when asymptomatic, but has the potential to become symptomatic, resulting in bone loss and kidney stones 3.
Treatment Options
- Parathyroidectomy is the only curative treatment for primary hyperparathyroidism, and is recommended in patients with symptoms and those with asymptomatic disease who are at risk of progression or have subclinical evidence of end-organ sequelae 2.
- Medical therapies, such as cinacalcet, can increase bone mineral density or reduce serum levels of calcium, but no single drug can do both 4, 5, 6.
- Cinacalcet has been shown to decrease serum calcium and parathyroid hormone serum levels in patients with primary hyperparathyroidism, and may be considered for patients who cannot or will not undergo surgery 5, 6.
Management and Monitoring
- Management of primary hyperparathyroidism should rely on an individual evaluation when counseling patients, taking into account the great variation in how the disease is manifested 4.
- Patients who do not undergo parathyroid surgery should be monitored for serum calcium concentrations and bone density 3.
- Combining resorptive agents with calcimimetics, such as cinacalcet, may be a useful approach, but more studies are needed to evaluate the effectiveness of this strategy 4.