w4 - Physiology of Pit- Tumorus, Prolactinoma, Acromegaly

Question 1

microadenoma is defined as ___, and macro is ____ in pit tuumours

Answer 1

less/than equal o 1cm

gr9er than 1cm

Question 2

pit tumours which are ‘too big’ will compress on

Answer 2

optic chiasm

craniel nerve 3,4,6

Question 3

‘too little’ pit tumours causes 5

Answer 3

hypoadrenalism (cortisol) 
hypothyroidsim (TSH)
hypogonadism (LH/FSH)
diabetes insipidus (ADH)
GH deficiency

Question 4

if tumour in ant pit, post pit is likely to be affected t/f

Answer 4

false

due to embroloyigical difference

Question 5

most common visual field defect

Answer 5

bitemporal hemianopia

Question 6

during stroke, a visual defect can occur, but is differen tthan bitemporal hemianopia, how is it different

Answer 6

only effects one eye

Question 7

causes of raised prolactin

pphysioLOGICal
PHARMACOLOGICAL
pathological

Answer 7

physiological

• breast feeding
• -pregnancy
• stress
• sleep

pharmacological

• dopamine antagonists (MEtoclopramide)
• antipsychotics (Phenothiazines)
• antidepressants (TCA,SSRIs)
• estrogens, coke

pathological

• hypothyroidism
• stalk lesions (IAtrogenic, RTA)
• prolactinoma

Question 8

signs and symptoms of prolactinoma in females

Answer 8

early presentation 
galactorrhea 
menstrual irregularity
ammenorrhoea
infertility

Question 9

signs and symptoms of prolactinoma in males

Answer 9

LATE Presentation
Impotence
Visual field abnormal
Headache
Ant pit malfunction

Question 10

investigations for prolactinoma

Answer 10

serum prolactin con
MRI pituitary (MICRO<1cm), pIt stalk, optic chiasma
visual fields
pit function tests

Question 11

treatment for prolactinoma

Answer 11

dopamine agonists

- cabergoline (1/2 /wk)

Question 12

side effects of dopamine agonists

Answer 12

nausea/vomiting
low mood
fibrosis (for bigger doses of same drug)

Question 13

acromegaly

Answer 13

too much growth hormoen

Question 14

how is acromegaly diagnosed

Answer 14

too much GH? measure
if so, IGF-1 will be produced, check this

suppression test
glucose tolerance test (GLucose inhibits GH)

Question 15

treatment for acromegaly

Answer 15

pit surgery 
retest GTT (GH<0.4ug/l) 
if gr8er 
-drugs
radio
-repeat surgerty

Question 16

drugs for acromegaly

Answer 16

1) somatostatin analogues
sandostatin LAR (IM)/Lanreotide (SC) (ocreotide)
(causes stinging/flatulance + diarrhoea/Ab pains/gallstones)

2) Dopamine agonist (works around 10/15%)
- cabergoline 3g/wk
- better if co-secreting prolactin

3) GH antagonist - Pegvisomant
- SC injection 10-30mg/d
- binds to GH receptor

Question 17

other than GH, what els is checked in follow up for acromegaly

Answer 17

IGF-1
other pit hormones - esp thyroid 
cancer surveillance 
-colon + tubulo-villous adenoma 
CV risk factors
sleep apnoea