Pituary Disease

Question 1

Describe the pituitary gland

Answer 1

Pea-sized
10-17 x 5-15 x 5-10 mm in size
Sits in bony cavity at the base of the brain
Consists of two lobes
Connected to the hypothalamus by a stalk
Hypothalamus produces hormones directly affecting activity of the pituitary

Question 2

What are the major causes of hypopituitarism?

Answer 2

Pituitary/parapituitary tumours
Radiotherapy
Pituitary infarction
Sheehan's syndrome
Trauma
Isolated hypothalamic releasing hormone deficiency

Question 3

What is growth hormone?

Answer 3

Released by the pituitary in response to growth hormone releasing hormone. Inhibited by somatostatin. Triggers the liver to produce IGF-1
Pulsatile release

Question 4

What are the symptoms of growth hormone deficiency?

Answer 4

In children: poor growth
In adults: increased abdominal fat, decreased muscle mass, impaired lipid profile, decreased muscle strength and exercise capacity, decreased cardiac function, decreased bone mineral density, impaired psychological wellbeing

Question 5

How is GH deficiency diagnosed?

Answer 5

GH stimulation tests

Question 6

What is the treatment for GH deficiency?

Answer 6

Hormone replacement therapy

Question 7

What are the symptoms of GH excess?

Answer 7

Acromegaly: acral enlargement, increased thickness of soft tissue of hands and feet
Gigantism, prognathism, jaw malocclusion, hypertrophy of frontal bones, cardiomyopathy, hypertension, visceromegaly, reproductive issues

Question 8

How is GH excess diagnosed?

Answer 8

OGTT, IGF-1

Question 9

What is the treatment for GH excess?

Answer 9

Surgery, radiotherapy or pharmacological
Drugs: somatostatin analogues such as octreotide and lanreotide
Pegvisomant is a GH receptor antagonist blocking IGF-1 secretion

Question 10

What are the side effects of LH/FSH deficiency?

Answer 10

Children: delayed puberty
Men: decreased libido, impotence, fertility and secondary sex characteristics
Also decreased muscle mass strength, mood and wellbeing. Osteporosis and anaemia
Women: decreased libido, menstrual disorders, infertility, dyspareunia, osteoporosis and premature atheroscelrosis

Question 11

How is LH/FSH deficiency diagnosed?

Answer 11

FSH/LH levels
Oestradiol levels
Menstruation history
Morning testosterone levels

Question 12

How is LH/FSH deficiency treated?

Answer 12

Hormone replacement therapy

Question 13

What are the causes of high prolactin?

Answer 13

Stress, pregnancy, lactation, sex, sleep, anti-depressants, hypothyroidism, prolactinoma, PCOS, ectopic secretion

Question 14

What are the symptoms of high prolactin?

Answer 14

Men: fatigue, low libido, headaches, visual loss, gynaecomastia
Women: amenorrhea, oligomenorrhoea, headaches, infertility, fatigue

Question 15

What is treatment for a prolactinoma?

Answer 15

Dopamine agonists (inhibits secretion of prolactin)
eg. bromocriptine, cabergoline, pergolide, quinagolide
Aims to return prolactin levels to normal, reduce tumour size and restore gonadal function
Decrease of serum prolactin within 2 hours. Normal within weeks/months
Tumour shrinks within 48 hours
Resistance possible - failure to shrink tumour less than 50%

Question 16

What are the symptoms of ACTH deficiency?

Answer 16

Fatigue, weakness, nausea, anorexia, weight loss, hypoglycaemia, hypotension, anaemia

Question 17

How is ACTH deficiency diagnosed?

Answer 17

9am serum cortisol and ACTH
Insulin tolerance test
Glucagon test
CRH test

Question 18

How is ACTH deficiency treated?

Answer 18

Hormone replacement therapy

Question 19

What are the symptoms of Cushing’s syndrome?

Answer 19

Weight gain, slow healing, increased risk of infections, fatigue, glucose intolerance

Question 20

How is Cushing’s syndrome diagnosed?

Answer 20

24 hour urinary free cortisol 
Midnight serum cortisol
Overnight low dexamethasone suppression test
9am ACTH
Imaging

Question 21

How is Cushing’s disease managed?

Answer 21

Pituitary surgery
Radiotherapy
Drugs
Bilateral adrenalectomy

Question 22

What are non functioning pituitary adenomas and how do they present?

Answer 22

Benign pituitary neoplasms from adenohypophyseal cells. No clinical evidence of hypersecretion
Cause headaches, visual loss, nerve palsy, tiredness, low libido

Question 23

What genetics are involved in pituitary tumours?

Answer 23

MEN1 and McCurie-Albright syndromes
Carney complex
FIPA
X-linked acrogigantism
Prevalence of AIP mutations