Pituitary Disorders

Question 1

This deck covers

Answer 1

Hypersecretion disorders:

• Cushing’s Disease
• Hyperprolactinaemia
• Acromegaly

Hyposecretion
including Cranial Diabetes Insipidus

Question 2

What is Acromegaly?

Answer 2

Excess production of Growth Hormone after the long bones fuse (i.e. in adults)

Question 3

How does acromegaly present?

Answer 3

• Enlarged hands/feet (rings dont fit, shoe size increases)
• Coarse facial features
• Thick lips & tongue
• Carpal Tunnel Syndrome
• Sweating

Question 4

What complications can arise from excess GH?

Answer 4

• Headaches
• Chiasmal Compression
• DM
• Hypertension
• Cardiomyopathy
• Sleep Apnoea
• Accelerated Osteoarthritis
• Colonic Polyps & adenoma

Question 5

How would you test someone for Acromegaly?

Answer 5

Visual Field Testing (chiasmal compression –> Bitemporal Hemianopia)

Screen potential patients for IGF-1 Elevation.

Confirm diagnosis with an OGTT, normally glucose loading suppresses GH.

MRI for pituitary tumour

Question 6

What is Cushing’s Disease?

Answer 6

Excessive Glucocorticoids due to the excessive ACTH release from pituitary

Question 7

How would cushing’s disease present?

Answer 7

• DM
• Na retention –> Hypertension & HF
• Thin skin
• Spontaneous purpura (looks like bruising)
• Proximal myopathy (weakness)
• Osteoporosis
• Pink striae
• Facial mooning, pendulous breasts & abdomen
• Hirsutism
• Oedema (fluid retention)

Question 8

What are the various causes of Cushing’s?

Answer 8

ACTH dependant:

• Pituitary Tumour
• Ectopic ACTH (Lung cancer)

ACTH independant:

• Adrenal tumour
• CCS therapy

Question 9

How do we test for Cushing;s?

Answer 9

Random Blood Cortisol

Overnight Dexamethasone Test & 24 hour free urine cortisol.

Confirm by repeating 24 hour urine cortisol.

Paired morning & midnight Cortisol & ACTH test

High Dose Dex Test (suppresses excess pituitary ACTH but not Ectopic)

Localise with MRI, CT adrenal r CT chest as appropriate

Question 10

What is hyperprolactinaemia?

Answer 10

Excessive prolactin in the blood

Question 11

What can cause hyperprolactinaemia?

Answer 11

Physiological - Pregnancy/lactation/stress

Pharmacological - Dopamine antagonists/oestrogens/antidepressants

Pathological - Primary hypothyroidism or Pituitary tumour

Question 12

How do we classify the scales of prolactinoma?

Answer 12

A microprolactinoma is <10mm

A macroprolactinoma is >10mm

Question 13

How does hyperprolactinaemia present?

Answer 13

Women:

• Galactorrhoea
• Menstrual irregularity
• Infertility

Men:

• Impotence
• Visual field abnormalities
• Headache
• Extraocular muscle weakness
• Other pituitary malfunction
• Eventual galactorhea

Men present later due to less obvious early warning symptoms

Question 14

How do you manage hyperprolactinaemia?

Answer 14

Test Serum PRL
Elevated? –> Pituitary MRI
Treat with dopamine agonist Cabergoline

Question 15

What is the primary management for all pituitary tumours?

Answer 15

Transphenoidal surgery to remove it +/- radiotherapy

Prolactinoma is the only one where we use drugs first

Question 16

What drug therapies are there for acromegaly?

Answer 16

Somatostatin Analogues

GH receptor antagonists

Question 17

What are the signs of hypopituitarism?

Answer 17

Tiredness
Weight gain
Depression
Lost libido
Impotence
Menstrual problems
Skin pallor
Reduced body hair

Question 18

What is Cranial Diabetes Insipidus?

Answer 18

A specific type of hypopituitarism in what there is no vasopressin released.

Question 19

How does CDI present?

Answer 19

No vasopressin means huge amounts of urine and consequent thirst

Risk of dehydration & hypokalemia

Question 20

What causes CDI?

Answer 20

Idiopathic
Trauma to pituitary (incl surgery)
brian tumours pressing on stalk

Question 21

How do we test for CDI?

Answer 21

Water deprivation test

Unlike normal they don’t conserve water, instead they keep pissing buckets.

Question 22

What could a pituitary tumour press on?

Answer 22

• Optic chiasm

- Cavernous sinus nerves