Hyperparathyroidism

Question 1

what is primary hyperparathyroidism?

Answer 1

• one or more of the parathyroid glands is over-secreting PTH despite normal serum calcium, which over time leads to hypercalcemia
• may be adenoma (85%), hyperplasia (14%), or carcinoma (<1%)

Question 2

what is secondary hyperparathyroidism?

Answer 2

• due to a disorder in calcium-phosphate-bone metabolism
• in response to low serum calcium levels as a result of another condition (e.g. CKD, or vitamin D deficiency), the parathyroid glands secrete PTH
• this may or may not normalise serum calcium levels, depending on the underlying condition

Question 3

what is tertiary hyperparathyroidism?

Answer 3

• may occur following a prolonged period of secondary hyperparathyroidism
• in response to chronic PTH secretion, the glands may become hyperplastic and begin to secrete PTH autonomously
• this can lead to hypercalcaemia as in primary hyperparathyroidism

Question 4

what are the risk factors for hyperparathyroidism?

Answer 4

• sporadic
• post-menopause
• previous radiation exposure to the neck
• lithium
• genetic (e.g. MEN)
• CKD

Question 5

what are the symptoms of hyperparathyroidism?

Answer 5

• asymptomatic
• fatigue
• polyuria
• polydipsia
• constipation
• abdominal pain
• vomiting
• confusion
• depression
• bone pain
• renal stones

Question 6

what is a mnemonic to remember the features of hypercalcaemia?

Answer 6

‘stones (renal stones), bones (bone pain), moans (abdominal pain, constipation) and groans (lethargy, depression)’

Question 7

what are the investigations for hyperparathyroidism?

Answer 7

• corrected calcium
• serum PTH
• vitamin D
• U&Es
• DEXA
• ? US KUB
• ? US neck / nuclear imaging (e.g. sestamibi scan)

Question 8

what is the acute management of severe hypercalcaemia?

Answer 8

• IV fluid
• IV bisphosphonate (e.g. pamidronate)

Question 9

what is the management of hyperparathyroidism?

Answer 9

• bisphosphonates
• cinacalcet
• ? phosphate binder
• ? vitamin D/calcium supplement
• partial/total parathyroidectomy

Question 10

what are the long-term complications of hyperparathyroidism?

Answer 10

• osteoporosis
• renal impairment/calculi
• pseudogout
• pancreatitis
• CVD