Hyperparathyroidism

Question 1

What is primary hyperparathyroidism (PHPT)?

Answer 1

An endocrine disorder in which autonomous overproduction of parathyroid hormone (PTH) results in derangement of calcium metabolism.

Question 2

What is the most common causes of PHPT?

Answer 2

In approximately 80% of cases, over-production of PTH is due to a single parathyroid adenoma and, less commonly, multi-gland involvement may occur.

Question 3

What are the risk factors for PHPT?

Answer 3

• Female sex
• Age >50-60
• Family history of PHPT
• Multiple endocrine neoplasia (MEN) 1, 2A or 4
• Current or historical lithium treatment
  *

Question 4

What are the signs of PHPT?

Answer 4

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Question 5

What are the symptoms of PHPT?

Answer 5

• Fatigue
• Poor sleep
• Myalgias
• Anxiety
• Depression
• Memory loss
• Bone pain
• Constipation
• Muscle cramps
• Paraesthesias

Question 6

What conditions are commonly linked to PHPT?

Answer 6

History of osteoporosis or osteopenia

Question 7

What investigations should be ordered for PHPT?

Answer 7

• Serum calcium
• Serum intact PTH with immunoradiometric or immunochemical assay

Question 8

What 2 parameters are needed for a diagnosis og PHPT?

Answer 8

Diagnosis of PHPT is confirmed with repeat measurements of serum calcium and serum intact parathyroid hormone (PTH). In PHPT both are normal-high or elevated.

Question 9

Why investigate serum calcium? And what may this show?

Answer 9

• If elevated, suggests disease. Diagnosis of PHPT requires elevated serum calcium, inappropriately unsuppressed serum intact PTH levels, and a normal or raised urinary calcium in the presence of normal renal function.
• From high-normal to raised.

Question 10

Why investigate using serum intact PTH with immunoradiometric or immunochemical assay? And what may this show?

Answer 10

• The diagnosis of PHPT, along with repeated elevated serum calcium, is confirmed with an inappropriate elevation in serum intact PTH. If calcium is high, and the feedback loop is intact, PTH should be low. If instead PTH is high, then it is inappropriately elevated and the diagnosis of PHPT is secured so long as the urinary calcium is not low (instead suggestive of familial hypocalciuric hypercalcaemia).
• From normal-high to elevated.