2: Hyperparathyroidism

Question 1

What is hyperparathyroidism

Answer 1

High parathyroid hormone

Question 2

What is primary hyperparathyroidism

Answer 2

Excess secretion PTH from parathyroid gland

Question 3

What is secondary hyperparathyroidism

Answer 3

Hypocalcaemia leads to excess PTH secretion

Question 4

What is tertiary hyperparathyroidism

Answer 4

Hypocalcaemia results in autonomous secretion of PTH from pituitary gland

Question 5

What causes 80% of primary hyperparathyroidism

Answer 5

Pituitary adenoma

Question 6

What are two other causes of primary hyperparathyroidism

Answer 6

• Hyperplasia (20%)

- Carcinoma (0.5%)

Question 7

What is the main cause of secondary hyperparathyroidism

Answer 7

• CKD

Question 8

What does CKD cause

Answer 8

Renal Osteodystrophy

Question 9

What is another cause of secondary hyperparathyroidism

Answer 9

Vitamin D Deficiency

Question 10

What causes tertiary hyperparathyroidism

Answer 10

Chronic Renal Failure

Question 11

What is malignant hyperparathyroidism

Answer 11

Release of PTHrp by cancers

Question 12

What 3 cancers release PTHrp

Answer 12

• Renal Cell Carcinoma
• Breast Cancer
• Squamous Cell Carcinoma

Question 13

What endocrine disorder can parathyroid also be related to

Answer 13

Multiple Endocrine Neoplasia (MEN)

Question 14

What is multiple endocrine neoplasia

Answer 14

Collection of hormone secreting tumours

Question 15

What is the inheritance of MEN

Answer 15

Autosomal Dominant

Question 16

What gene is mutated in MEN 1

Answer 16

MEN1 gene

Question 17

How does MEN 1 usually present

Answer 17

Hypercalcaemia

Question 18

What are the 3 P’s of MEN 1

Answer 18

1. Parathyroid
2. Pancreas (Insulinoma, Gastrinoma)
3. Pituitary

Question 19

What tumours are other tumours are present in MEN1

Answer 19

Adrenal

Thyroid

Question 20

What gene is mutated in Men IIa

Answer 20

RET Oncogene

Question 21

What cancer is men IIa most commonly associated with

Answer 21

Medullary Thyroid Cancer (90%)

Question 22

What is medullary thyroid cancer

Answer 22

Cancer of C-cells

Question 23

What are 2P’s of Men IIa

Answer 23

Pheochromocytoma

Parathyroid

Question 24

What gene is mutated in men IIb

Answer 24

RET oncogene

Question 25

What P is present in men IIb

Answer 25

Phaeochromocytoma

Question 26

What other cancers occur in men IIb

Answer 26

- Neurofibromatosis

Question 27

What is men IIb specially associated with

Answer 27

- Marfinoid body habits | - NF

Question 28

What does neurofibromatosis cause

Answer 28

Bilateral vesicular schwanomas

Question 29

How is hyperparathyroidism usually found

Answer 29

Incidentally, symptoms are often retrospective

Question 30

What is the menumonic for symptoms of hypercalcaemia

Answer 30

stones, bones, groans and psychiatric overtones

Question 31

Explain 'stones'

Answer 31

Renal stones

Question 32

Explain 'bones'

Answer 32

- Pain - Weakness - Fractures - Osteoporosis

Question 33

Explain 'groans'

Answer 33

- Tiredness - Duodenal ulcer - Pancreatitis - Polyuria, Polydipsia

Question 34

Explain 'psychiatric overtones'

Answer 34

- Depression

Question 35

What are symptoms of hyperparathyroidism due to BP

Answer 35

- HTN

Question 36

what is the role of PTH

Answer 36

- Stimulates osteoclasts and hence bone reabsorption and serum calcium - Inhibits phosphate reabsorption - Increases vitamin D

Question 37

explain renal osteodystrophy

Answer 37

- CKD reduces hydroxylation and activation of vitamin D - This reduces calcium reabsorption in the gut and renal tubules - causing hypocalcaemia - Hypocalcaemia causes hyperparathyroidism - This leads to bone reabsorption

Question 38

what is first-line investigation for hyperparathyroidism

Answer 38

Bone profile

Question 39

what is adjusted calcium accounting for

Answer 39

Albumin. | As low albumin will cause hypocalcaemia on assay (despite normal calcium)

Question 40

how will phosphate present in hyperparathyroidism

Answer 40

Low

Question 41

when will PTH be high

Answer 41

1' and 2' hyperparathyroidism

Question 42

explain PTH in malignant hyperparathyroidism

Answer 42

PTH will be low. PTHrp released from cancers is not detected on the assay. However, will cause hypercalcaemia which activates negative feedback inhibiting PTH release

Question 43

if pTH is normal what should you consider

Answer 43

lithium thiazide diuretics familial hypocalciuric hypocalcaemia

Question 44

what is second line for hyperparathyroidism

Answer 44

X-ray | DEXA scan

Question 45

what scan is used to detect pituitary adenoma

Answer 45

Technitium and Sestimibi scanning

Question 46

what is osteitis fibrosa cystica

Answer 46

occurs due to severe periosteal reabsorption. Presents with: - Brown tumours - Erosions - Cysts - Pepper pot skull

Question 47

how is mild hyperparathyroidism managed

Answer 47

Increase fluid intake (prevent stones) | Reduce calcium intake

Question 48

what is first-line for moderate hyperparathyroidism

Answer 48

Parathyroidectomy

Question 49

what are 4 indications of parathyroidectomy

Answer 49

- Osteoporosis - Renal Stones - High Serum Calcium - Decrease renal function

Question 50

what is an alternative to parathyroidectomy

Answer 50

calcimimmetics (cinacalcet)

Question 51

what is role of cinacalcet

Answer 51

Increase sensitivity of chief cells to calcium and therefore reduces parathyroid secretion

Question 52

what artery innervates parathyroid glands

Answer 52

Inferior thyroid artery

Question 53

where do superior parathyroid glands arise

Answer 53

3rd pharyngeal pouch

Question 54

where do inferior parathyroid glands arise

Answer 54

4th pharyngeal pouch

Question 55

what can thyroid surgery lead to

Answer 55

hypocalcaemia

Question 56

what is required to monitor following parathyroidectomy

Answer 56

Calcium Phosphate Magnesium

Question 57

what is given following parathyroidectomy

Answer 57

Calcium | Vitamin D replacement