Pituitary Physiology

Question 1

What are the pituitary and peripheral steroid hormones

Answer 1

ACTH and cortisol

Question 2

What are the pituitary and peripheral thyroid hormones

Answer 2

TSH and thyroxine

Question 3

What are the pituitary and peripheral sex hormones

Answer 3

LH/FSH and testosterone or oestradiol

Question 4

What are the pituitary and peripheral growth hormones

Answer 4

GH and IGF-1

Question 5

What are the pituitary and peripheral steroid hormones

Answer 5

Only pituitary hormone which is prolactin

Question 6

What can be compressed if a pituitary tumour grows extensively

Answer 6

Cranial nerves
Optic chiasma
Internal carotid arteries
Sphenoid sinus

Question 7

By what route do we usually remove a pituitary tumour

Answer 7

Though the sphenoid sinus

Question 8

If we think the pituitary is secreting too much hormone, what test do we do

Answer 8

One to try and suppress the hormone

Question 9

If we think the pituitary is secreting too little hormone, what test do we do

Answer 9

One to try and stimulate the hormone

Question 10

How do we know if there is a problem in a dynamic test

Answer 10

There will be no response to either suppression or stimulation of the hormone

Question 11

How can we do a dynamic pituitary test

Answer 11

Insulin stress test

Question 12

Describe the normal result of a stress test to insulin

Answer 12

The blood glucose will decrease dramatically for the first half hour before insulin, growth hormone and cortisol will all increase to compensate and react to the hypoglycaemic environment

Question 13

What patients should not be subjected to an insulin stress test

Answer 13

Those with epilepsy or ischaemic heart disease

Question 14

What should be used instead of an insulin stress test in patients with epilepsy or ischaemic heart disease

Answer 14

prolonged Glucagon test

Question 15

How can we test ADH

Answer 15

Deprive the patient of water and make them dehydrated

Question 16

How can we diagnose Diabetes Insipidus

Answer 16

If there is an abnormal Urine/serum Osmolality is less than 2, 8 hours after a water deprivation test

Question 17

What is the name of a pituitary tumour

Answer 17

Microadenoma

Question 18

What is the name of pituitary tumour >1cm

Answer 18

Macroadenoma

Question 19

What are the chances of a non-functioning pituitary being benign

Answer 19

90%

Question 20

Do non-funcitoning pituitary adenomas produce hormones

Answer 20

No

Question 21

Why are non functioning adenomas a problem

Answer 21

They can wipe out the cells of the pituitary that do produce hormones

Question 22

What can a non functioning pituitary adenoma cause

Answer 22

Hypoadrenalism
Hypothyroidism
Hypogonadism
Growth hormone deficiency

Question 23

What is bitemporal hemianopia

Answer 23

When the temporal visual field is obliterated due to a pituitary tumour

Question 24

What are some physiological causes of raised prolactin

Answer 24

Breast feeding
Pregnancy
Stress
Sleep

Question 25

What drugs can cause an increase of prolactin

Answer 25

Dopamine antagonists Antipsychotics Antidepressants

Question 26

What is elevated in an underachieve thyroid

Answer 26

TRH and TSH

Question 27

If there is elevated, TRH what can occur

Answer 27

Increased stimulation of prolactin

Question 28

What are some examples of cases where there will be an increase in prolactin

Answer 28

Hypothyroidism | Road accidents or iatrogenic causes of stalk lesion

Question 29

What are some of the clinical signs in a female of increased prolactin

Answer 29

Galactorrhoea Menstrual irregularity Ammenorrhoea Infertility

Question 30

What are some of the clinic signs in a male of increased prolactin

Answer 30

Impotence Visual field abnormalities Headache Anterior pituitary malfunction

Question 31

Males will present earlier than females with increased prolactin

Answer 31

No - they always present late

Question 32

What are the main investigations for prolactinoma

Answer 32

Prolactin concentrations MRI pituitary Visual fields Pituitary function tests

Question 33

What should also be checked when checking for prolactin in the serum

Answer 33

Thyroid function test

Question 34

What are the 3 main dopamine agonists to treat prolactinoma

Answer 34

Bromocriptine Quinagolide Cabergoline

Question 35

What do dopamine agonists do

Answer 35

reduce prolactin levels and can make tumours shrink

Question 36

What dopamine agonist is usually used in prolactinoma and why

Answer 36

Cabergoline (Dostinex) | it has the least side effects

Question 37

What is the cause of acromegaly

Answer 37

Growth hormone excess

Question 38

What are some features of acromegaly

Answer 38

thickened and soft skin, large jaw, sweaty, large hands

Question 39

What are some side effects of acromegaly

Answer 39

``` Hypertension, cardiac failure Headaches Snoring/ sleep apnoea Diabetes mellitus Early CV death colonic polyps and colon cancer ```

Question 40

How can we make a diagnosis of acromegaly

Answer 40

GTT suppression test | - GH will have no change after glucose

Question 41

What other tests should be done for suspected acromegaly

Answer 41

Visual field CT or MRI pituitary scan Pituitary function tests

Question 42

What are the treatment options for acromegaly

Answer 42

Pituitary surgery External radiotherapy to pituitary fossa Rest GTT

Question 43

What are some side effects of somatostatin analogues

Answer 43

Local stinging Short term include flatulence, diarrhoea and abdominal pains Long term include gastritis and gallstones

Question 44

What are the 2 more commonly used somatostatin analogues in acromegaly

Answer 44

Sandostatin LAR and Lanreotide autogel

Question 45

Why is Pegvisomant hardly ever used

Answer 45

It is extremely expensive and most patients will respond to other treatment

Question 46

What should be involved in an acromegaly follow up

Answer 46

Other pituitary hormones should be checked Cancer surveillance Cardiovascular risk factors Sleep apnoea

Question 47

Dopamine inhibits release of prolactin. True or false

Answer 47

True

Question 48

What does ACTH do to the adrenal glands

Answer 48

Stimulates them to produce cortisol

Question 49

What is the first line treatment for prolactinoma

Answer 49

Dopamine agonists

Question 50

What is the most common cause of an acromegalic headache

Answer 50

Vascular effects such as increased blood flow