mix of endo

Question 1

Diabetes insipidus is due to lack of ___

Answer 1

ADH

Question 2

classification of Dibaetes insipidus

Answer 2

cranial or nephrogenic

Question 3

2 symptoms of diabetes insipidus

Answer 3

polyuria & polydipsia

Question 4

type of diabetes where the collecting ducts of the kidney do not respond to ADH

Answer 4

Nephrogenic diabetes insipidus

Question 5

type of diabetes where the hypothalamus does not produce ADH

Answer 5

cranial diabetes insipidus

Question 6

drug causing nephrogenic DI

Answer 6

lithium

Question 7

electrolyte imbalance in diabetes insipidus

Answer 7

hypernatraemia

Question 8

osmolality findings in diabetes insipidus

Answer 8

low urine osmolality
&
high serum osmolality

Question 9

test for diagnosing diabetes insipidus?

Answer 9

Water deprivation test
/
desmopressin stimulation test

Question 10

where is ADH released from

Answer 10

posterior pituitary gland

Question 11

ectopic ADH secretion?

Answer 11

small cell lung ca

Question 12

mechanism of ADH

Answer 12

acts on distal convoluted tubule & collecting duct to increase water reabsorption independant of sodium

ADH stimulates the insertion of aquaporin-2 channels onto the luminal membrane, allowing free entry of water

Question 13

sodium level in SiADH

Answer 13

euvolemic hyponatraemia

due to dilution

Question 14

urine osmolality is ___

Answer 14

low

Question 15

what can severe hyponatraemia cause?

Answer 15

seizures & reduced consciousness

Question 16

medications that can cause SiADH

Answer 16

• thiazide diuretics
• carbmazepine
• cyclophosphamide
• antipsychotivs
• SSRI
• NSAIDs

Question 17

why is it important to correct sodium level slowly?

Answer 17

prevent; ‘Central pontine myelinolysis’

Question 18

e.g. of ADH receptor blockers

Answer 18

Tolvaptan

Question 19

1st phase of central pontine myelinolysis & why?

Answer 19

water moves from blood to cells in the brain across BBB. causing brain to swell

• encephalopathic
• confused

Question 20

2nd phases of central pontine myelinolysis

Answer 20

demyelination of the neurones, particularly in the pons. May present as cog&behavioural changes, spastic quadriparesis, pseudobulbar palsy

Question 21

what is ADH produced by?

Answer 21

magnocellular neurons in the paraventricular & supraoptic nuclei of the hypothalamus

Question 22

what triggers release of ADH

Answer 22

rising plasma osmolality

Question 23

urinary test results in SiADH

Answer 23

high urine osmolality
&
high urinary sodium

Question 24

what produces calcitonin?

Answer 24

parafollicular C cells

Question 25

effect of Calcitonin on: a) intestines b) bones c) kidneys

Answer 25

Intestines - reduces calcium absorption

Bones - stimulates osteoblasts & inhibits osteoclasts

Kidneys - inhibits phosphate reabsorption

Question 26

what electrolyte imbalance calcitonin be used to treat?

Answer 26

hypercalcaemia

Question 27

what marker can be used for recurrence of medullary thyroid cancer?

Answer 27

calcitonin

Question 28

inheritance pattern of MEN 1&2

Answer 28

autosomal dominant

Question 29

3 P’s of MEN 1

Answer 29

• Parathyroid hyperplasia
• Pituitary adenoma
• Pancreatic tumours

Question 30

syndrome characterised by gastrinoma & recurrent peptic ulcers & diarrhoea

Answer 30

Zollinger-Ellison syndrome

Question 31

what mutation causes MEN 2

Answer 31

mutation of RET proto-oncogene

Question 32

3 conditions predominantly in MEN 2

Answer 32

• Parathyroid hyperplasia
• Medullary thyroid ca
• Phaechromocytoma

Question 33

difference between MEN 2a & 2b

Answer 33

2a - normal appearance & parathyroid hyperplasia is common

2b - marfanoid habitus & parathyroid hyperplasia is rare