Pituitary Disorders

Question 1

size of microadenoma

Answer 1

<1cm-1cm

Question 2

size of macroadenoma

Answer 2

> 1cm

Question 3

physiological causes of raised prolactin

Answer 3

breast feeding
pregnancy
stress
sleep

Question 4

pharmacological causes of raised prolactin

Answer 4

dopamine antagonists e..g metoclopramide
phenothiazines
TCA
SSRIs
oestrogens
cocaine

Question 5

pathological causes of raised prolactin

Answer 5

hypothyroid
stalk lesions
prolactinoma

Question 6

how does hypothyroidism cause raised prolactin?

Answer 6

dopamine requires tyrosine- thyroxine is made from tyrosine and iodine

Question 7

what is a prolactinoma?

Answer 7

adenoma of the pituitary gland that overproduces prolactin

Question 8

presentation in females with prolactinoma

Answer 8

earlier presentation usually
galactorrhoea
menstrual irregularity
infertility
visual field abnormality
headache

Question 9

presentation in males with prolactinoma

Answer 9

impotence
visual field abnormality
headache

Question 10

diagnosis of prolactinoma

Answer 10

high serum prolactin
MRI
visual fields e.g. bitemporal hemianopia

Question 11

prolactin levels in macroadenoma?

Answer 11

20,000+

Question 12

prolactin levels in microadenoma?

Answer 12

3,000+

Question 13

management of prolactinoma

Answer 13

dopamine agonist e.g. cabergoline causes tumour shrinkage

Question 14

adverse of cabergoline

Answer 14

nausea
vomiting
low mood
fibrosis of heart valves and retroperitoneum

Question 15

what is acromegaly?

Answer 15

excess of GH

Question 16

presentation of acromegaly

Answer 16

children gigantism (if before epiphyseal fusion)
thickened soft tissues
hypertension, early CV death
headaches
DM
sleep apnoea, snoring
carpal tunnel 
colonic polyps and colon cancer

Question 17

thickened soft tissues examples in acromegaly

Answer 17

increased shoe size
spade hands
wedding ring too tight

Question 18

diagnosis of acromegaly

Answer 18

measure IGF1
OGTT
visual fields
visualise the pituitary e.g. MRI

Question 19

why do you measure IGF1 in acromegaly?

Answer 19

GH secretion is pulsatile

GH stimulates release of IGF1 from the liver

Question 20

describe the OGTT in acromegaly

Answer 20

75g PO glucose and check GH every 30 minutes

normal= <0.4ug/l after glucose whereas in acromegaly it is unchanged/risen

Question 21

management of acromegaly

Answer 21

transsphenoidal pituitary surgery
radiotherapy
somatostatin analogues
dopamine agonists
GH antagonists
cancer surveillance, cardiovascular RF and sleep apnoea management

Question 22

what can radiotherapy on the pituitary lead to?

Answer 22

hypopituitarism

Question 23

somatostatin analogue use in acromegaly

Answer 23

sandostatin, octreotide and lareotide

relieve headaches and reduce tumour size

adverse if GI upset

Question 24

dopamine agonist use in acromegaly

Answer 24

cabergoline and bromocriptine

better if co-secreting prolactin)

Question 25

what is Cushing's disease?

Answer 25

an excess of cortisol caused by pituitary adenoma secreting excess ACTH

Question 26

what is Cushing's syndrome?

Answer 26

signs/symptoms of excess cortisol caused by adrenal adenomas, ectopic or pseudo causes

Question 27

ectopic production of ACTH

Answer 27

thymus lung pancreas

Question 28

pseudo production of ACTH

Answer 28

alcohol | steroids

Question 29

presentation of Cushing's

Answer 29

myopathy, proximal wasting (proteolysis) thin skin, striae, bruising OP hypertension, obesity, DM (stress hormone) oedema (mineralocorticoids) virilism, hirutism, oligo/amenorrhoea (androgen excess)

Question 30

diagnosis of Cushing's

Answer 30

screening= urine free cortisol and diurnal variation low dose dexamethasone test measure ACTH

Question 31

management of Cushing's disease

Answer 31

hypophysectomy (radiotherapy and bilateral adrenalectomy if recurs)

Question 32

management of Cushing's if unfit for surgery?

Answer 32

metyrapone

Question 33

what is panhypopituitarism?

Answer 33

absence of pituitary hormones

Question 34

causes of panhypopituitarism

Answer 34

pituitary tumours surgery granulomatous disease

Question 35

presentation of panhypopituitarism

Answer 35

``` hypothyroid face abdominal obesity infertility, menstrual irregularity gynaecomastia loss of facial hair ```

Question 36

diagnosis of panhypopituitarism

Answer 36

PFTs | can do suppression/stimulation tests

Question 37

management of panhypopituitarism

Answer 37

hormone replacement

Question 38

which hormone is abused in sport?

Answer 38

GH

Question 39

why is cortisol replaced before levothyroxine in panhypopituitarism?

Answer 39

activates sympathetics and can cause adrenal crisis

Question 40

adverse of testosterone therapy?

Answer 40

risks making cancers grow more polycythaemia (stroke/MI) hepatitis (LFTs)

Question 41

cranial DI

Answer 41

problem with ADH in posterior pituitary

Question 42

causes of cranial DI

Answer 42

familial (DIDMOAD) | acquired (tumour, trauma, idiopathic, inflammation)

Question 43

diagnosis of cranial DI

Answer 43

water deprivation test/ desmopressin

Question 44

water deprivation test result in cranial DI

Answer 44

osmol ratio >2 is negative | if low and improves after desmopressin, then cranial not nephrogenic

Question 45

management of cranial DI

Answer 45

desmospray or desmopressin tablets/injections