Pituitary Pathology

Question 1

describe hypopituitarism

Answer 1

reduced function of the pituitary gland, can be isolated to a specific hormone or all hormones - panhypopituitarism

Question 2

list causes of hypopituitarism

Answer 2

hypothalamic - tumour, genetic, infection eg TB, syphilis or meningitis
pituitary stalk - trauma, surgery, aneurysm
pituitary - radiation, non-functioning adenoma or ischaemia

Question 3

what is sheenans syndrome

Answer 3

pan hypopituitarism due to ischaemia and necrosis following a post partum haemorrhage, presents with failure to lactate

Question 4

how does hypopituitarism present

Answer 4

insufficiency of specific hormones eg hypothyroidism etc

Question 5

what are the signs and symptoms of reduced GHRH

Answer 5

atherosclerosis and lack of balance

Question 6

what are the signs and symptoms of reduced GRH in males and females

Answer 6

males - ED, reduced libido and muscle bulk

females - amenorrhoea, reduced fertility and libido

Question 7

what is the management of hypopituitarism

Answer 7

once underlying cause is established treat it and manage any hormone deficiencies correctly

Question 8

what type of tumour is a pituitary tumour normally

Answer 8

bengin adenoma

Question 9

define a microadenoma and macroadenoma

Answer 9

microadenoma - <1cm

macroadenoma - >1cm

Question 10

what is a non-functioning adenoma

Answer 10

a pituitary tumour that does not secrete any hormones

Question 11

what is the most common type of pituitary tumour

Answer 11

prolactinoma, secretes excess prolactin

Question 12

how does a pituitary tumour present

Answer 12

pressure headache
bitemporal hemianopia
hormonal symptoms depending on what is being over or under secreted

Question 13

list the investigations for a pituitary tumour

Answer 13

MRI of brain

hormonal testing

Question 14

how is a pituitary tumour treated

Answer 14

surgical removal via trans-sphenoidal approach

Question 15

list some physiological causes of hyperprolactinaemia

Answer 15

breast feeding
pregnancy
stress
sleep

Question 16

list some pathological causes of hyperprolactinaemia

Answer 16

prolactinoma
hypothyroidism
compression of pituitary stalk through trauma

Question 17

list some drugs that cause hyperprolactinaemia

Answer 17

anti-emetics eg metaclopramide and anti-psychotics

both inhibit dopamine

Question 18

describe the presentation of hyperprolactinaemia in both females and males

Answer 18

females - galactorrhoea, reduced libido, amenorrhoea

males - reduced facial hair, ED, galactorrhoea less common

Question 19

what is the first line treatment of hyperprolactinaemia

Answer 19

dopamine agonists eg cabergoline and bromocriptine

must also stop any dopamine antagonists

Question 20

what is the second line treatment of hyperprolactinaemia

Answer 20

surgical excision of the tumour if drugs are ineffective

Question 21

what is acromegaly

Answer 21

excessive growth hormone production usually due to pituitary adenoma

Question 22

acromegaly is usually part of what condition

Answer 22

MEN 1 tumours

Question 23

what is the presentation of acromegaly

Answer 23

giantism in children if bones haven’t fused
growth of soft tissues in hand, feet, jaw and tongue
widening of the nose
pituitary tumour symptoms

Question 24

what investigations are carried out for acromegaly

Answer 24

IGF1 and glucose - high

glucose tolerance test to confirm diagnosis

Question 25

what is the 1st line treatment of acromegaly

Answer 25

surgical excision of tumour with radiotherapy

Question 26

what is the 2nd line treatment of acromegaly

Answer 26

give somatostatin analogue (reduces secretions of GH and will shrink tumour) examples are octreotide and sandostatin

Question 27

what are the side effects of somatostatin analogues

Answer 27

GI upset and gallstones

Question 28

are dopamine agonists effective in treating acromegaly

Answer 28

yes as they suppress GH secretion but do not cure the condition

Question 29

what is diabetes insipidus

Answer 29

passing large volumes of urine (>3L each day)

Question 30

define central DI and nephrogenic DI

Answer 30

central - occurs when pituitary fails to secrete ADH eg due to tumour, genetics or sarcoidosis nephrogenic - occurs when the kidneys fail to respond to the secretion of ADH eg due to CKD, genetics or drugs such as lithium

Question 31

how does diabetes insipidus present

Answer 31

polydipsia polyuria dehydration

Question 32

what test diagnoses diabetes insipidus

Answer 32

water deprivation test, assesses the bodys ability to concentrate urine by measuring urine osmolarity

Question 33

diabetes insipidus is excluded when serum osmolarity is

Answer 33

>600

Question 34

to determine the difference between central and nephrogenic DI what is given following water deprivation test

Answer 34

ADH, central DI will respond to it and urine osmolarity is restored

Question 35

outline the management of central and nephrogenic DI

Answer 35

central - synthetic ADH (desmopressin) | nephrogenic - thiazide diuretics to generate hyponatraemia which drives water reabsorption in the kidneys