Hyperparathyroidism

Question 1

What is osteoitis fibrosa cystica?

Answer 1

Skeletal disorder resulting in a decrease in bone mass and the formation of cyst like brown tumours in and around the bone.
Caused by hyperparathyroidism = stimulates the activity of osteoclasts
Osteoclastic bone resorption results in elevated calcium levels and softening of bones.

Question 2

Where is PTH produced?

Answer 2

Chief cells in parathyroid glands

Question 3

What is primary hyperparathyroidism and what are the features?

Answer 3

Excess PTH due to a tumour of the parathyroid glands
Leads to hypercalcaemia
Treatment is surgery

‘Bones, stones, abdominal groans and psychic moans’ (polydipsia, peptic ulceration, pancreatitis, bone pain, renal stones, depression)

Question 4

What happens in secondary hyperparathyroidism?

Answer 4

Decreased vitamin D or chronic renal failure leads to hypocalcaemia, resulting in a compensatory increase in PTH

Over time, hyperplasia of the parathyroid glands occurs

The serum calcium level will either be low or normal. Phosphate is increased.

Treat by correcting the underlying cause

Question 5

What happens in tertiary hyperparathyroidism?

Answer 5

Tertiary HPTH occurs when secondary HPTH goes on for too long. The baseline of how much PTH is secreted dramatically increases, so even when the underlying cause is treated PTH levels still remain high.

Leads to a high absorption of calcium and thus hypercalcaemia.

Question 6

In what group of patients is primary hyperparathyroidism most commonly seen?

Answer 6

Elderly females with an unquenchable thirst and an inappropriately normal or raised PTH level

Most commonly due to a solitary adenoma

Question 7

What are the investigations of hyperparathyroidism?

Answer 7

Technetium-MIBI subtraction scan

Pepperpot skull

Question 8

What is the treatment of hyperparathyroidism?

Answer 8

Definitive treatment is total parathyroidectomy
Conservative management may be offered if the calcium level is less than 0.25 the upper level of normal AND the patient is >50 with no end organ damage

Question 9

What are the indications for surgery for primary hyperparathyroidism?

Answer 9

Age <50
Elevated serum calcium >1mg/dL above normal
Episode of life threatening hypercalcaemia
Nephrolithiasis
T score lower than -2.5

Question 10

What are the indications for surgery for secondary hyperparathyroidism?

Answer 10

Bone pain
Persistent pruritis
Soft tissue calcifications