Parathyroid

Question 1

What is the affect of the parathyroid hormone?

Answer 1

• normally secreted in response to low Ca2+
• increases osteoclast activity
• increases Ca2+ reabsorption in kidneys
• activates vitamin D3

Question 2

Overall affect of normal parathyroid hormones?

Answer 2

• increase calcium

- decrease phosphate

Question 3

Where is vitamin D3 activated?

Answer 3

• kidneys

- by PTH

Question 4

Where are calcium sensing receptors located?

Answer 4

• parathyroid glands

- G-protein coupled receptor

Question 5

What are symptoms of hypercalcaemia?

Answer 5

• Stones
• Bones
• groans
• psychiatric overtones
• thirst
• dehydration

Question 6

Chronic affect of hypercalcaemia?

Answer 6

• myopathy

- fractures

Question 7

What are some causes of hypercalcaemia?

Answer 7

• primary hyperparathyroidism

- malignancy

Question 8

High Calcium
High PTH
Low urinary excretion of CAa2+

What could it be?

Answer 8

• Familial hypocalciuria hypercalcaemia

Question 9

Causes of primary hyperparathyroidism?

Answer 9

• adenoma

- hyperplasia of parathyroid gland

Question 10

Tests and results for primary hyperparathyroidism?

Answer 10

• high calcium
• high PTH
• increased urine calcium
• low phosphate

Question 11

Treatment of primary hyperparathyroidism?

Answer 11

• increase fluids
• avoid thiazides
• removal of gland

Question 12

Explain hypercalcaemia associated with malignancy?

Answer 12

• PTHrP from solid tumours

- drives osteoclast activity

Question 13

What is PTHrP

Answer 13

• parathyroid related protein
• released from a malignant tumour
• increases calcium levels

Question 14

Treatment of hypercalcaemia?

Answer 14

• fluids
• bisphosphonates
• surgery

Question 15

What scan should be performed before surgery of the parathyroid glands?

Answer 15

• Sestamibi scan

Question 16

Explain secondary hyperparathyroidism?

Answer 16

• low Ca2+
• high PTH
• physiological response to low Ca2+ or vitamin D

Question 17

Explain tertiary hyperparathyroidism?

Answer 17

• autonomous overproduction of PTH
• high PTH
• high calcium

Question 18

Explain Familial hypocalciuria hypercalcaemia (FHH)

Answer 18

• genetic
• autosomal dominant
• low excreted calcium
• high serum calcium
• calcium receptor less sensitivity

Question 19

Symptoms of hypocalcaemia?

Answer 19

• paraesthesia
• muscle cramps and weakness
• fatigue
• Chvostek’s sign
• Trousseaus sign

Question 20

Explain Chvostek’s sign?

Answer 20

• hypocalcaemia

- twitching of facial muscles upon tapping of facial nerve

Question 21

Explain Trousseaus sign?

Answer 21

• contraction of hands/feet when inflating BP cuff

Question 22

Emergency treatment of hypocalcaemia?

Answer 22

• Prolonged QT

- IV calcium gluconate

Question 23

Test results with hypocalcaemia?

Answer 23

• decreased PTH
• Decreased Ca2+
• increased phosphate

Question 24

Long term treatment of hypocalcaemia?

Answer 24

• calcium supplements

- vitamin D tablets

Question 25

Explain pseudohypoparathyroidism?

Answer 25

• low calcium
• high PTH
• bone abnormalities

Question 26

Explain pseudo-pseudohypoparathyroidism?

Answer 26

• morphological features

- normal biochemistry

Question 27

Calcium release from cells is dependant on what?

Answer 27

• magnesium

Question 28

Calcium levels in magnesium deficiency?

Answer 28

• intracellular calcium high

Question 29

Causes of hypomagnesaemia?

Answer 29

• alcohol

- drugs (PPI and thiazide)

Question 30

Calcium levels in osteomalacia?

Answer 30

• low calcium

- high PTH

Question 31

Chronic renal disease can cause what?

Answer 31

• secondary hyperparathyroidism