Pituitary

Question 1

pituitary adenomas are the main cause of pituitary ________

Answer 1

hyperfunction

Question 2

T/F: pituitary adenoma has more correlation with MEN2a

Answer 2

F: more with MEN1

Question 3

functional pituitary adenomas tend to be classed by…

Answer 3

cells involved

Question 4

which pituitary tumour is the most common

Answer 4

prolactinoma

Question 5

prolactinoma occurs due to…

Answer 5

-ve dopamine control (dopamine inhibits prolactin)

Question 6

aetiology of inc prolactin

Answer 6

Physiology: breast feeding
Pathology: adenoma
Pharma: dopamine antagonist

Question 7

s/s of prolactinoma

Answer 7

early in females: galactorrhea, menstrual irregularity, amenorrhea

males- late: impotence, bitemporal hemianopia

Question 8

what is dx of prolactinoma

Answer 8

Sr prolactin >5000

Question 9

mx of prolactinoma

Answer 9

dopamine antagonists, surgical removal

Question 10

pituitary adenoma may be non-functional- why may this still be an issue

Answer 10

can compress optic chiasma, CN 3,4,6 etc

Question 11

what is the main surgical technique for pituitary adenoma removal

Answer 11

transphenoidal surgery

Question 12

acromegaly is a tumour of…

Answer 12

growth hormone secretion resulting in inc GH

Question 13

s/s of acromegaly

Answer 13

thick soft tissue (large tongue, forehead), sweaty, HT, headaches, gigantism

Question 14

ix for acromegaly

Answer 14

glucose tolerance test (as GH is insulin-like growth factor), suppression test of GH +ve if >0.4mg/l

Question 15

tx for acromegaly

Answer 15

1st line: surgery
2nd line: somatostatin, dopamine antagonists
3rd line: Radiotherapy

Question 16

Cushing’s is an inc in…

Answer 16

cortisol

Question 17

difference between Cushing’s disease and Cushing’s syndrome

Answer 17

Cushing’s disease= ACTH dependent- pituitary adenoma

Cushing’s syndrome: ACTH independent- adrenal adenoma, pseudocushing’s etc

Question 18

3 types of Cushing’s

Answer 18

cushion’s disease, cushion’s syndrome, paraneoplastic cushings(ACTH released from small cell lung cancer)

Question 19

s/s of Cushing’s

Answer 19

round person, thin limbs
moon face, buffalo hump
myopathy (muscle wasting)

Question 20

ix for Cushing’s

Answer 20

overnight dexamethasone suppression test (low dose)
then high dose given to identify origin
KNOW THE RESULTS

Question 21

mx for Cushing’s

Answer 21

pituitary cause= surgery, radiotherapy

adrenal: surgery

Question 22

pituitary hypofunction is due to…

Answer 22

no specific hormone- usually panhypopituitarism

Question 23

aetiology of pituitary hypofunction

Answer 23

iatrogenic* (surgery), tumours, sudden haemorrhage, ishaemic necrosis, granulomatous inflammation, hypothalamic lesions

Question 24

s/s of hypofunction

Answer 24

obesity, hair loss, dry skin, dull face, growth retardation, menstrual irregularities, infertility, gynecomastia

Question 25

mx of hypofunction

Answer 25

hormone replacement therapy (hydrocortisone, ADH, thyroxine, GH etc)

Question 26

which hormone do athletes use illegally

Answer 26

GH

Question 27

craniopharyngeoma is a cause of hypo function, what is it?

Answer 27

bengin tumour of the hypothalamus (remnant from Rethke's pouch). may present with headache, visual disturbance

Question 28

posterior pituitary hyperfunction

Answer 28

SIADH- syndrome of inappropriate ADH

Question 29

what is SIADH

Answer 29

ectopic production of ADH leading to large amounts of ADH= concentrated urine

Question 30

why does SIADH cause a big Na dec in blood

Answer 30

large amounts being reabsorbed in kidney tubules > diluted blood so diluted Na [ ]

Question 31

2 etiological features of SIADH

Answer 31

post pit secreting too much ADH: iatrogenic, head injury non-osmotic stimuli: hypovolaemia, hypotension ectopic: small cell lung cancer

Question 32

what are the s/s of SIADH

Answer 32

usually only due to hyponatraemia- seizures, headache, fatigue, muscles aches, confusion

Question 33

what are some findings for U&Es of SIADH

Answer 33

hyponatrameia, high Na in urine

Question 34

mx of SIADH

Answer 34

fluid restriction, tolvaptan (ADH blocker)

Question 35

main complication of SIADH Na resuc

Answer 35

central pontine myelinolysis: Na reintroduced too fast so brain cells don't have time to adjust- H2O leaves brain cells too fast

Question 36

posterior pituitary hypo function is....

Answer 36

Diabetes insipidus

Question 37

what is DI

Answer 37

lack of ADH or lack of ADH response = dilute urine as ADH causes reabsorption of H2O from tubules to blood, high Sr Na

Question 38

types of DI

Answer 38

cranial: hypothalamus doesn't produce ADH nephrogenic: collecting ducts don't respond to ADH (resistant)

Question 39

s/s of DI

Answer 39

polyuria, polydipsia, hypernatraemia

Question 40

main sign of hypernatraemia

Answer 40

oedema

Question 41

Ix for DI

Answer 41

low urine osmolarity, high serum osmolarity | water deprivation test: norm urine: SR osmolarity >2. desmopressin then given, if ratio normalises then it is cranial DI

Question 42

mx of DI

Answer 42

cranial- desmopressin | nephrogenic: thiazide & NSAIDs