Pit pathology

Question 1

What are the three broad categories of pathology of the pit gland?

Answer 1

Too little hormone
Too much hormone
Too big

Question 2

How do you test for too much/little hormone?

Answer 2

Blood tests

Question 3

How do you test for a pit gland that is too big?

Answer 3

Imaging- MRI or US

Question 4

In a dynamic endocrine test for too much hormone what do you do?

Answer 4

See if you can suppress the hormone

Question 5

In a dynamic endocrine test for too little hormone what do you do?

Answer 5

See if you can stim hormone

Question 6

Give examples of a dynamic endocrine test for too little hormone?

Answer 6

Insulin stress test
Water deprivation test
Synacthen test

Question 7

How does the insulin stress test work?

Answer 7

Drop blood glucose to <2.2 using insulin to stim cortisol and GH release

Question 8

What is a safer alternative to the insulin stress test?

Answer 8

Prolonged glucagon test

Question 9

What should cortisol rise to in the insulin stress test for it to be normal?

Answer 9

> 500

Question 10

What should GH rise to in the insulin stress test for it to be normal?

Answer 10

> 7 micrograms/l

Question 11

How does the water deprivation test work?

Answer 11

Deprive of liquid for 8h and check is Ur/Serum osmol ratio is >2.

Question 12

What does a Ur/Serum osmol ratio of <2 suggest?

Answer 12

Diabetes insipidus

Question 13

When do you not need to do a water deprivation test?

Answer 13

If the baseline reading is >2

Question 14

What is the second part of the water deprivation test?

Answer 14

Give desmopressin. If it improves after DDAVP then problem with pit/hypo if not problem with kidneys.

Question 15

What are two causes of too little pit hormone?

Answer 15

Panhypopituitarism

Tumour in one cell type squeezing out others

Question 16

What is the main cause of too little pit hormone?

Answer 16

Panhypopituitarism

Question 17

What causes panhypopituitarism?

Answer 17

Pit tumour
Pit apoplexia
Lung/breast met
Infection- TB/sarcoidosis
Vascular disease 
Trauma/ iatrogenic
Hypothalamus disease- TB/meningitis
Autoimmune 
Sheehan's syndrome
Congenital
Drugs

Question 18

What is Sheehan’s syndrome?

Answer 18

Necrosis of pit due to blood loss during birth

Question 19

How can panhypopituitarism present?

Answer 19

Menstrual irregularities 
Infertility/impotence
Gynaecomastia
Abdo obesity
Dry skin/ pale
Hypothyroid face
Growth retardation
Lack of sexual charcteristics

Question 20

How can you test for panhypopituitarism?

Answer 20

Blood tests for:
TSH/fT4
LH/FSH (naturally increased post menopause)
Prolactin
IGF-1
Test/oestrogen
Random cortisol
Synacthen/ITT for cortisol
Symptoms of DI

Question 21

How do you treat panhypopituitarism?

Answer 21

Hormone replacement: 
Thyroxine
Hydrocortisone- Give first
ADH
GH
Testosterone- in males
Oestrogen/progesterone- in females

Question 22

How important is GH in adults?

Answer 22

Not needed but good for quality of life.

Question 23

How is testosterone normally given?

Answer 23

IM injection or daily topical

Question 24

What are some side effects of testosterone?

Answer 24

Enlarged prostate- Does not cause cancer
Hepatitis from tablets.
Blood count issues
Fusion of growth plates

Question 25

What two sizes of pit tumours are there?

Answer 25

Microadenoma <1cm | Macroadenoma >1cm

Question 26

What to categories of pit tumours are there?

Answer 26

Functioning | Non-functioning

Question 27

What pathology can non-functioning pit tumours cause?

Answer 27

Too big | Too little hormone

Question 28

What pathologies can a 'Too big' tumour cause?

Answer 28

Compression of optic chiasm Compression of CN 3, 4, 6 Compression of carotid artery

Question 29

What pathologies can a 'Too little hormone' cause?

Answer 29

``` Hypoadrenalism Hypothyroidism Hypogonadism GH defects DI- rare as anterior tumours rarely impact on post ```

Question 30

What pathologies can a functioning pit tumour cause?

Answer 30

``` Too much hormone: Prolactin GH ACTH TSH ```

Question 31

What is the most common functional pit adenoma?

Answer 31

Prolactinoma

Question 32

Are TSH secreting tumours common or rare?

Answer 32

Rare

Question 33

What is a craniopharyngioma?

Answer 33

Tumour derived from the remnants of Rathke's pouch

Question 34

How do craniopharyngiomas present?

Answer 34

Cystic 5-15 and 60-70 Headaches + visual disturbances

Question 35

What can cause increased prolactin production?

Answer 35

Prolactinoma Physio- Breastfeeding, pregnancy, sleep Pharma- DA antagonists: antipsychotics/depressants Patho- Hypothyroidism (TRH can stim prolactin release) Stalk lesion (prevent DA reaching pit)

Question 36

How does increased prolactin production present in females?

Answer 36

Early presentation Galactorrhoea Menstrual irregularities Infertility

Question 37

How does increased prolactin production present in males?

Answer 37

``` Late presentation Impotence Visual field abnormalities Headaches Ant pit function ```

Question 38

How do you test for increased prolactin production?

Answer 38

Serum prolactin conc MRI Visual fields Pit function tests

Question 39

How do you treat increased prolactin production?

Answer 39

DA agonists- will shrink but not cure: | Cabergoline- best option

Question 40

What complications can too little prolactin production cause?

Answer 40

None known

Question 41

What can excessive GH production produce?

Answer 41

Acromegaly

Question 42

How can acromegaly present?

Answer 42

``` Giant if occurs before epiphyseal fusion Thickened soft tissue Hypertension -> LVH -> CF Headaches- due to vascular complications DM due to increased blood glucose Colon cancer and polyps ```

Question 43

How do you test for acromegaly?

Answer 43

``` Blood IGF-1 and GH levels- not diagnostic GTT Insulin suppression test Visual fields MRI/CT pit function test ```

Question 44

How do you perform a GTT for acromegaly?

Answer 44

Give 75g oral glucose. Check GH levels at: 0, 30, 60, 120 If <0.4 then normal

Question 45

How do you treat acromegaly?

Answer 45

Pit surgery- transsphenoidal common Radiotherapy Somatostatin analogues (suppress GH)- Can cause gall stones GH antagonists- Block GHR but can increase tumour size- last resort.

Question 46

What complications can a lack of growth hormone cause?

Answer 46

Growth retardation in children | Increased abdo fat and decreased muscle in adults

Question 47

Is GH essential in adults?

Answer 47

No but needed for a good quality of life

Question 48

What can lack of LH and FSH cause?

Answer 48

Genital atrophy

Question 49

What is pituitary apoplexy?

Answer 49

Hemorrhage into pit leading it be compressed and die

Question 50

What happens after a pit apoplexy?

Answer 50

When it drains get an open cavern and no pit

Question 51

What kind of prolactin levels can prolactinomas cause?

Answer 51

Big- 15000mU/l due to prolactin production | Small- ~1500mU/l due to pressing on stalk

Question 52

What physiological things can cause increase prolactin levels?

Answer 52

Just about anything: Exercise Stress

Question 53

What is the main chemical treatment for acromegaly?

Answer 53

Somatostatin analogues

Question 54

In panhypopituitary which treatment should you give first and how long for?

Answer 54

Cortisol replacement for 72hrs | Then thyroxine

Question 55

Can you give thyroxine to someone who is steroid deplete?

Answer 55

No!!!

Question 56

Which type of pit tumour (micro or macro) tends to be the most hormonally active?

Answer 56

Micro

Question 57

How does a macroadenoma cause issues?

Answer 57

Non-functioning but produces problems due to mass effect