Pituitary

Question 1

Order of anterior pituitary failure

Answer 1

Good Grief That’s Cortical Profanity

Gonadotrophins, GH, TSH, ACTH, Prolactin

Question 2

Post-partum

Can’t breastfeed then becomes really tired

Answer 2

Sheehan’s syndrome following PPH = pituitary infarct
No breastfeeding as no prolactin
Become really tired due to no TSH, ACTH

Question 3

Procedure pituitary function testing

Answer 3

Give Insulin 0.15U/kg, TRH, GnRH
Insulin causes hypoglycaemia - stimulates GH, ACTH > cortisol
Measure Cortisol, GH, TSH, LH/FSH at 30, 60, 90 and 120m intervals
LH + FSH should peak at 30 or 60m - only apply post puberty

Question 4

Pituitary adenoma - >1cm vs. <1cm

Answer 4

Macroadenoma vs. microadenoma

Question 5

Pituitary adeoma - functioning vs. non-functioning

Answer 5

Functioning - produce hormones + compress structures (e.g. prolactinoma, somatotrophinoma)
Non-functioning - don’t produce hormones + compress structures
Compression of optic chiasm = bitemporal hemianopia

Question 6

Raised prolactin

Prolactinoma vs. Non-functioning adenoma

Answer 6

Prolactinoma = functioning adenoma producing lots of prolactin = Prolactin >6000 (massively raised)
Non-functioning adenoma = compresses pituitary stalk _ vessels from hypothalamus - reduces dopamine supply so increases prolactin secretion = Mildly raised prolactin

Question 7

Tx pituitary failure

Answer 7

Complete pituitary hormone replacement - hydrocortisone + thyroxine + oestrogen + GH
If prolactinoma - CABERGOLINE (dopamine agonist)

Question 8

Acromegaly (somatotrophinoma)

Answer 8

Ix: OGTT (IGF-1 not enough)
Tx: Surgery, radiotherapy, cabergoline, octreotide