Calcium Disorders

Question 1

List clinical features of hypercalcaemia

Answer 1

Thirst, dehydration
Confusion
Polyuria
Myopathy
Osteopenia, fractures
Hypertension
Abdo pain (renal stones, pancreatitis)

Question 2

List the main causes of hypercalcaemia

Answer 2

Hyperparathyroidism
Malignancy
Drugs (vit D, thiazides)
TB, sarcoidosis
High cell turnover (Paget's)
FHH

Question 3

If you could do one test to investigate hypercalcaemia, what would you do?

Answer 3

Measure PTH levels

Question 4

Outline management of hypercalcaemia

Answer 4

Fluid replacement
Loop diuretic
Biphosphonate

Question 5

What is the difference between primary, secondary and tertiary hyperparathyroidism?

Answer 5

Primary: overactivity of PT gland due to adenoma
Secondary: physiological response to low Ca
Tertiary: PT becomes autonomous after years of secondary hyperparathyroidism

Question 6

In primary hyperparathyroidism, PTH levels are high/low and calcium levels are high/low

Answer 6

PTH high

Calcium high

Question 7

In secondary hyperparathyroidism, PTH levels are high/low and calcium levels are high/low

Answer 7

PTH high

Calcium low

Question 8

What investigation is done for hyperparathyroidism?

Answer 8

Sestamibi scan - localises adenoma

Question 9

What is FHH?

Answer 9

Familial hypercalciuric hypercalcaemia

Autosomal dominant disease where CaSR is mutated

Question 10

List clinical features of hypocalcaemia

Answer 10

Paraesthesia
Muscle cramps/tetany/weakness
Fatigue
Bronchospasm
Chovstek sign
Trousseau sign

Question 11

What is Chovstek sign in hypocalcaemia?

Answer 11

Tapping over facial nerve produces a twitch of muscle on the ipsilateral side

Question 12

What is Trousseau sign in hypocalcaemia?

Answer 12

Carpopedal spasm when BP cuff is inflated + held for 3mins

Question 13

What are the main causes of hypocalcaemia?

Answer 13

Hypoparathyroidism
Vitamin D deficiency
Chronic renal failure

Question 14

List causes of hypoparathyroidism

Answer 14

Congenital (DiGeorge syndrome)
Trauma/iatrogenic
Autoimmunity
Low magnesium

Question 15

What would levels of calcium, phosphate, PTH and ALP be like in hypoparathyroidism?

Answer 15

Calcium low
Phosphate high
PTH low
ALP normal

Question 16

Which disease(s) are extreme manifestations of vitamin D deficiency?

Answer 16

Osteomalacia (adults)

Rickets (children)

Question 17

What would levels of calcium, phosphate, PTH and ALP be like in osteomalacia?

Answer 17

Calcium normal/low
Phosphate low
PTH normal
ALP high

Question 18

Outline treatment for (chronic) vitamin D deficiency

Answer 18

Vitamin D3 tablets
Calcitriol
Alfacalcidol

Question 19

What is pseudo-hypoparathyroidism?

Answer 19

Resistance to PTH, causing hypocalcaemia (even though PTH may very well be high)

Question 20

Which gene is defect in pseudo-hypoparathyroidism?

Answer 20

GNAS1 (causing dysfunction of G-protein)

Question 21

What (the fck) is pseudo-pseudo-hypoparathyroidism?

Answer 21

Phenotypically the individual has pseudo-hypoparathyroidism, but biochemical aspects are normal (i.e. normal calcium)

Question 22

Outline treatment of hypocalcaemia

Answer 22

IV calcium gluconate (acute)
Calcium supplements
Vitamin D supplements

Question 23

What are calcium, PTH, ALP and phosphate levels like in hyperparathyroidism?

Answer 23

Calcium high
PTH high
ALP normal/high
Phosphate normal

Question 24

What are calcium, PTH, ALP and phosphate levels like in bone malignancy?

Answer 24

Calcium high
PTH low
ALP high
Phosphate normal

Question 25

What are calcium, PTH, ALP and phosphate levels like in FHH?

Answer 25

Calcium high
PTH normal/high
ALP normal
Phosphate high

Question 26

What are calcium, PTH, ALP and phosphate levels like in hypoparathyroidism?

Answer 26

Calcium low
PTH low
ALP normal
Phosphate normal/high