Pituitary Disease

Question 1

What are pituitary adenomas?

Answer 1

Benign tumours of the glandular tissue

Can be life threatening - mass effects/secretory actions

Question 2

How are pituitary adenomas classified according to size?

Answer 2

Microadenoma <1cm

Macroadenoma >1cm

Question 3

How are pituitary adenomas classified according to function?

Answer 3

Functioning

Non-functioning

Question 4

How do non-functioning adenomas present?

Answer 4

Mass Effects
-bitemoporal heminaopia
-ocular palsies
-signs of raised ICP
-hypothalamic compression sx
Hypopituitarism

Question 5

How do functioning adenomas present?

Answer 5

Acromegaly
Hyperprolactinemia
Cushing’s syndrome
Mass effects as in non-functioning adenomas

Question 6

What causes bitemoporal heminaopia?

Answer 6

Compression of optic chiasm

Question 7

What causes ocular palsies?

Answer 7

Compression of CN III, IV & VI

Question 8

What causes hypopituitarism?

Answer 8

Destruction of normal functioning tissue

Question 9

What are the symptoms of hypothalamic compression?

Answer 9

Altered appetite
Thirst
Abnormal sleep/wake cycle

Question 10

What are the signs of raised ICP?

Answer 10

Headache
Nausea/Vomiting
Confusion (time - location+place)
Double vision
Pupils w/o light response

Question 11

What is hyperprolactinaemia?

Answer 11

Excessive prolactin production,stimulating milk production and inhibiting GnRH + gonadotropin production

Question 12

What are the symptoms of hyperprolactinaemia?

Answer 12

Galactorrhoea (f)
Subfertility (m)
Oligo/Amenorrhoea
Decreased libido
Arrested puberty
Osteoporosis (long term)

Question 13

What is acromegaly?

Answer 13

Syndrome characterised by excessive GH production with effects on skeletal/soft-tissue growth

Question 14

What are the symptoms of acromegaly?

Answer 14

Change in appearance
Increased hand/foot size
Tiredness
Excessive sweating
Poor libido
Headaches
Visual deterioration
Sx of DM
Sx of hypopituitarism

Question 15

What are the signs of acromegaly?

Answer 15

Protruding mandible
Prominent supraorbital ridge
Interdental separation
Large tongues
Spade-like hands/feet
Tight rings
Visual field defects
Hypertension

Question 16

What effect does excess GH have in children?

Answer 16

Gigantism (if prior to epiphyseal plate closure)

Question 17

What is Cushing’s syndrome?

Answer 17

Syndrome characterised by Sx of increased circulating glucocorticoid

Question 18

What are the symptoms of Cushing’s?

Answer 18

Central weight gain
Change of appearance
Depression
Insomnia
Poor libido
Thin skin/easy bruising
Excess hair growth/acne
Sx of DM

Question 19

What are the signs of Cushing’s?

Answer 19

Moon face
Frontal balding
Striae
Hypertension
Pathological fractures
Dorsal fat pad (buffalo hump)
Proximal myopathy

Question 20

What is the management for a prolactinoma?

Answer 20

Dopamine agonists (Ropinarole/Bromocriptine) lifelong
Reduce tumours but sx arise again if medications stopped

Question 21

What are the side effects of Ropinarole/Bromocriptine?

Answer 21

Nausea/Vomiting
Dizziness
Syncope
Pulmonary/cardiac/retroperitoneal fibrosis

Question 22

What is the most common cause of acromegaly?

Answer 22

Almost exclusively a pituitary tumour

Paraneoplastic release of GH from non-pituitary tumours

Question 23

What investigations are appropriate in suspected acromegaly/gigantism?

Answer 23

IGF-1 (raised, correlated w/ GH)

OGTT (failure to suppress GH secretion, >2mcg/ml at 2hrs)

Question 24

What is the management for acromegaly?

Answer 24

Somatastatin analogues shrink tumour

Surgery via transphenoidal approach

Question 25

What is the most common cause of Cushing's Syndrome?

Answer 25

Exogenous administration of steroids

Question 26

What are the endogenous causes of Cushing's syndrome?

Answer 26

Cushing's disease - increased ACTH from pituitary (65%) Ectopic ACTH - non pituitary tumour, SCLC (10%) Excess adrenal cortisol - adrenal tumour/nodular hyperplasia (25%)

Question 27

What investigations are appropriate in suspected Cushing's syndrome?

Answer 27

``` Cortisol (raised) Dexamethasone suppression (failure to suppress cortisol) 24hr urinary free cortisol ```

Question 28

What investigations can be used to localize the cause of Cushing's syndrome?

Answer 28

Plasma ACTH low - adrenal likely, CT ACTH detectable --> 48hr, high dose dexamethasone suppression test: -complete/partial suppression = pituitary (MRI sella) -no suppression = ectopic (CXR) CRH --> cortisol raised w/ pituitary sources of ACTH

Question 29

What is the management for a pituitary adenoma?

Answer 29

Transphenoidal surgery

Question 30

What is the main complication of delaying surgery?

Answer 30

Permanent loss of vision due to prolonged chiasm compression

Question 31

What is Panhypopituitism?

Answer 31

Defective production of all pituitary hormones

Question 32

How does Panhypopituitism present?

Answer 32

Fatigue, myalgia, hypotension (GH) Diabetes insipidus (ADH) Hypothyroidism (TSH)

Question 33

What are the pituitary causes of Panhypopituitism?

Answer 33

``` 1o/metastatic tumour Surgical removal/irradiation of pituitary Ischaemic necrosis (hypotensive shock) ```

Question 34

What are the hypothalamic causes of Panhypopituitism?

Answer 34

1o brain tumour (craniopharyngoma) Infarction Sarcoid Infection

Question 35

How is Panhypopituitism diagnosed?

Answer 35

Pituitary hormones (low) Effector gland hormones (low) Low response to stimulation tests Imaging

Question 36

What is the main cause of diseases of the neurohypothesis?

Answer 36

Damage to hypothalamus - tumour invasion - infarction

Question 37

How do diseases of the neurohypothesis present?

Answer 37

``` Diabetes insipidus (polyuria & polydipsia) if low ADH SIADH if high ADH ```