Anterior pituitary - hypersecretion

Question 1

What is the most common cause of hypersecretion of pituitary hormones?

Answer 1

Pituitary tumour

Question 2

Describe how pituitary tumours can lead to bitemporal hemianopia

Answer 2

Temporal aspects of light hit nasal aspects of retina, fibres from nasal aspect meet at optic chiasm, compression by tumour –> bitemporal hemianopia

Question 3

What pathology is caused by an excess of ACTH?

Answer 3

Cushing’s

Question 4

What pathology is caused by an excess of TSH?

Answer 4

Thyrotoxicosis

Question 5

What pathology is caused by an excess of LH/FSH?

Answer 5

Precocious puberty

Question 6

What pathology is caused by an excess of prolactin?

Answer 6

hyperprolactinaemia

Question 7

What pathology is caused by an excess of GH?

Answer 7

Gigantism/ acromegaly

Question 8

Recall the pathologies associates with excess GH in adults and children

Answer 8

Adults: acromegaly
Children: gigantism

Question 9

Describe the onset of acromegaly

Answer 9

Insidious

Question 10

Recall 5 things that grow excessively in acromegaly

Answer 10

1. Periosteal bone
2. Cartilage
3. Fibrous tissue
4. Connective tissue
5. Internal organs (heart/spleen/liver)

Question 11

Recall the 11 clinical features associated with acromegaly. Which of these are the main two?

Answer 11

HYPERHIDOSIS
HEADACHE
Facial changes
Prognathism
Carpal tunnel
Barrel chest
Kyphosis
Diabetes
Hypertension
Cardiomyopathy
Increased cancer risk

Question 12

Recall the facial changes associated with acromegaly

Answer 12

Enlargement of:

1. supraorbital ridges
2. Nose
3. lips
4. Tongue

Question 13

Recall and explain 2 methods of diagnosing acromegaly

Answer 13

1. Measure IGF-1 (not pulsatile, elevated in acromegaly)

2. Oral glucose test (acromegaly -> failure to suppress GH)

Question 14

What is the first-line treatment for acromegaly?

Answer 14

Surgery to remove adenohypophysial tumour

Question 15

Recall 2 options for medical treatment of acromegaly, and give an example of each

Answer 15

Somatostatin analogues (octreotide)
DA agonists (cabergoline)

Question 16

Recall 3 side effects of cabergoline

Answer 16

Nausea
Diarrhoea
Gall stones

Question 17

What is cabergoline’s main clinical use?

Answer 17

Pre-operative tumour reduction

Question 18

Why is octreotide known as “endocrine cyanide”?

Answer 18

Inhibits many peptides (not GH specific)

Question 19

Describe the effect of hyperprolactinaemia on GnRH

Answer 19

Suppresses GnRH pulsatility

Question 20

Recall 4 symptoms of hyperprolactinaemia in women

Answer 20

Galactorrhoea
Amenorrhoea
Loss of libido
Infertility

Question 21

Recall 4 symptoms of hyperprolactinaemia in men

Answer 21

Loss of libido
Erectile dysfunction
Infertility

Question 22

Recall the hormone-receptor interaction controlling prolactin secretion

Answer 22

Dopamine - D2 receptors on lactotrophs –> inhibition of prolactin release

Question 23

What is the first-line treatment for hyperprolactinaemia? Name 2 examples

Answer 23

D2 receptor agonist: cabergoline, bromocriptine

Question 24

Recall 5 side-effects of cabergoline

Answer 24

1. Pathological gambling
2. Dyskinesia
3. Postural hypotension
4. Depression
5. Nausea and vomiting