Hypoparathyroidism

Question 1

Define hypoparathyroidism

Answer 1

Occurs when there is relative or absolute deficiency of parathyroid hormone (PTH) leading to hypocalcaemia and hyperphosphatemia

Question 2

What is the biochemistry results for hypoparathyroidism

Answer 2

Low Serum Calcium

Low or inappropriately normal PTH

High Phosphate

Question 3

Name four potential causes of hypoparathyroidism

Answer 3

Secondary to thyroidectomy

Pseudohypoparathyroidism – insensitivity of target cells (PTH will be high)

Autoimmune destruction of the gland

Radiation

Question 4

Name some clinical features of hypoparathyroidism

Answer 4

Can be asymptomatic

Symptoms are manifestations of the hypocalcaemia

Tetany: muscle twitching, cramping and spasm

Trousseau’s sign: carpal spasm if the brachial artery occluded by inflating the blood pressure cuff and maintaining pressure above systolic

Chvostek’s sign: tapping over parotid causes facial muscles to twitch

ECG: prolonged QT interval

Question 5

What is Trousseau’s sign

Answer 5

Carpal spasm if the brachial artery occluded by inflating the blood pressure cuff and maintaining pressure above systolic

Question 6

What is Chvostek’s sign

Answer 6

Tapping over parotid causes facial muscles to twitch

Question 7

What is an ECG features suggestive of hypoparathyroidism

Answer 7

Prolonged QT interval

Question 8

How is hypoparathyroidism managed

Answer 8

Calcium supplements and calcitriol

+/-

Parathyroid hormone replacement

Question 9

What is calcitriol

Answer 9

Biologically active form of vitamin D

Question 10

When is parathyroid hormone replacement considered as adjunctive therapy in managing hypoparathyroidism

Answer 10

In patients lacking response to calcium supplements and calcitriol alone.