Pituitary Disease

Question 1

how are pituitary tumours classified?

Answer 1

by their size

Question 2

what is a pituitary adenoma <1cm called?

Answer 2

microadenoma

Question 3

what is a pituitary adenoma >1cm called?

Answer 3

macroadenoma

Question 4

why can a benign pituitary adenoma still be very damaging?

Answer 4

there is very little space available to them for growth before causing problems

Question 5

what structures can a pituitary adenoma compress?

Answer 5

optic chiasma
cranial nerves
internal carotid arteries

Question 6

how is a pituitary adenoma managed?

Answer 6

transsphenoidal surgery to remove

hormone replacement

Question 7

what are three physiological causes of raised prolactin?

Answer 7

pregnancy
stress
lack of sleep

Question 8

what drugs can cause a raised prolactin?

Answer 8

anything that reduces dopamine levels

dopamine antagonists, anti-psychotics

Question 9

what are three pathological causes of raised prolactin?

Answer 9

hypothyroidism
lesions on the pituitary stalk
prolactinoma

Question 10

how does hypothyroidism lead to a raised prolactin?

Answer 10

TRH stimulates prolactin - elevated in hypothyroidism due to loss of negative feedback

Question 11

what value of prolactin suggests a prolactinoma?

Answer 11

over 5000

Question 12

do men or women with prolactinoma present earlier?

Answer 12

women

Question 13

how does a prolactinoma present in females?

Answer 13

galactorrhoea
menstrual irregularities
infertility

Question 14

how does a prolactinoma present in males?

Answer 14

impotence
visual field abnormalities
anterior pituitary problems

Question 15

what medication is used to treat a prolactinoma?

Answer 15

dopamine agonists

Question 16

name a dopamine agonist

Answer 16

cabergoline

Question 17

what causes acromegaly?

Answer 17

GH excess

Question 18

what does GH excess in children cause?

Answer 18

gigantism

Question 19

how is a diagnosis of acromegaly confirmed?

Answer 19

measure IGF-1

OGTT

Question 20

what is the gold standard test for diagnosing acromegaly?

Answer 20

OGTT

Question 21

how is an OGTT performed?

Answer 21

give 75g glucose orally and measure GH every 30 mins for two hours

Question 22

what is a normal response to an OGTT?

Answer 22

GH suppresses to <0.4 after glucose

Question 23

what is the response to an OGTT in acromegaly?

Answer 23

GH unchanged or raised

Question 24

what is the main treatment for acromegaly?

Answer 24

pituitary surgery

Question 25

what drugs can be used to manage acromegaly?

Answer 25

somatostatin analogues dopamine agonists GH antagonists

Question 26

what management for acromegaly is done if drugs fail?

Answer 26

radiotherapy

Question 27

what is cushing's syndrome?

Answer 27

excess cortisol

Question 28

what is the gold standard test for diagnosing cushing's syndrome?

Answer 28

low dose dexamethasone suppression test

Question 29

what is the main cause of cushing's syndrome?

Answer 29

a pituitary adenoma - called cushing's disease

Question 30

what factors could create a false positive when doing tests for cushing's disease?

Answer 30

alcohol depression steroid medication

Question 31

how would a pituitary cause of cushing's be diagnosed?

Answer 31

low dose dex test = abnormal | ACTH = slightly raised

Question 32

how would a adrenal cause of cushing's be diagnosed?

Answer 32

low dose dex test = abnormal | ACTH = low

Question 33

how would a ectopic cause of cushing's be diagnosed?

Answer 33

low dose dex test = abnormal | ACTH = very raised

Question 34

name some of the main causes of hypopituitarism

Answer 34

pituitary tumours brain tumours invading side effect of surgery

Question 35

name some signs and symptoms of anterior hypopituitarism

Answer 35

``` menstrual irregularities infertility impotence gynaecomastia obesity dry skin ```

Question 36

what is given in hypopituitarism to replace TSH?

Answer 36

thyroxine 100-150mcg/day

Question 37

what is given in hypopituitarism to replace ACTH?

Answer 37

hydrocortisone 10-15 split over the day - largest dose in the morning

Question 38

what is given in hypopituitarism to replace ADH?

Answer 38

desmopressin tablets or desmospray

Question 39

what is given in hypopituitarism to replace GH?

Answer 39

subcutaneous GH nightly

Question 40

what is given in hypopituitarism to replace sex steroids?

Answer 40

HRT/COCP for females | testosterone for males

Question 41

what is the test used to diagnose diabetes insipidus?

Answer 41

water deprivation test

Question 42

what is involved in the water deprivation test?

Answer 42

nil by mouth for 8-12 hours check serum and urine osmolalities for 8h and then 4h after giving IM DDAVP

Question 43

what are the options for treating diabetes insipidus?

Answer 43

desmospray | desmopressin oral tablets