Hyperthyroidism

Question 1

TSH stimulates which processes?

Answer 1

uptake of iodine into the thyroid gland and proteolytic enzyme to release thyroxine from follicles into the bloodstream.

Question 2

how much thyroxine is stored in the thyroid gland?

Answer 2

enough for 1 month

Question 3

Body attacking thyroid so it cannot make T3 and T4 is an example of?

Answer 3

primary hypothyroidism

Question 4

treatment for primary hypothyroidism

Answer 4

levothyroxine until TSH falls into normal range

Question 5

What happens in graves disease?

Answer 5

antibodies bind to and stimulate TSH receptor in thyroid causing smooth goitre

Question 6

graves disease is an example of?

Answer 6

primary hyperthyroidism

Question 7

In Grave’s disease, what happens to the metabolism?

Answer 7

speeds up

Question 8

which scan is used to diagnose graves disease, plummers disease and viral thyroiditis?

Answer 8

radioactive iodine uptake scan

Question 9

what happens in exophthalmos? Which disease is it associated with?

Answer 9

an antibody binds to muscles behind the eye and stimulates growth factor receptors causing them to bulge, graves disease

Question 10

pretibial myxoedema (swelling of shins) is associated with?

Answer 10

graves disease

Question 11

what type of goitre is caused by graves disease?

Answer 11

smooth goitre

Question 12

what type of goitre is caused by Plummer’s disease?

Answer 12

toxic nodular goitre

Question 13

How does Plummer’s disease work?

Answer 13

benign adenoma that is overactive making thyroxine

Question 14

What does excess thyroxine do to the sympathetic nervous system?

Answer 14

sensitises beta adrenoreceptors to ambient levels of adrenaline and noradrenaline

Question 15

what are 5 symptoms of hyperthyroidism?

Answer 15

weight loss
increased appetite
heat intolerance
diarrhoea
lid-lag

Question 16

what causes lid-lag in hyperthyroidism?

Answer 16

excess T3 makes adrenaline hold eyelids back

Question 17

propyl-thio uracil and carbimazole are which type of drug?

Answer 17

thionamides (anti-thyroid)

Question 18

how do the thionamides work?

Answer 18

block thyroid peroxidase and prevent synthesis of T3/T4

Question 19

how does potassium iodide work?

Answer 19

used in preparation of hyperthyroid patients for surgery and turns everything off for 10 days because of iodine overload

Question 20

how does radioiodine work?

Answer 20

goes into thyroid and destroys it

Question 21

name 2 side effetcs of thionamides

Answer 21

agranulocytosis (reduction in neutrophils), rashes

Question 22

What are 5 symptoms of thyroid storm?

Answer 22

• hyperpyrexia > 41 degrees
• accelerated tachycardia/ arrythmia
• cardiac failure
• delirium / frank psychosis
• hepatocellular dysfunction; jaundice

Question 23

how many of the 5 symptoms for thyroid storm must be present for diagnosis?

Answer 23

2

Question 24

what is the follow up for thionamide treatment?

Answer 24

Follow up after 18 months, maybe try them longer if not working –> surgery/ radioidine

Question 25

state 3 risks of thyroidectomy

Answer 25

voice change, losing parathyroid glands, anaesthetic

Question 26

what are beta blockers used for?

Answer 26

control of symptoms while waiting for thionamides to work

Question 27

how would viral thyroiditis present in a radioiodine scan?

Answer 27

no iodine uptake - nothing

Question 28

painful dysphagia, hyperthyroidism, pyrexia and thyroid inflammation are a sign of?

Answer 28

viral thyroiditis

Question 29

what is the presentation of viral thyroiditis?

Answer 29

1 month hyperthyroidism, 1 month hypothyroidism, then normal again

Question 30

why do viral thyroiditis patients have hyperthyroidism during the first month?

Answer 30

thyroid cells damaged and release lots of stored thyroxine

Question 31

A 30 year old woman attends clinic and presents you with a letter from a private health clinic. She has been experiencing palpitations. The letter contains the following results:

fT4 30 pmol/L (9 - 23)

fT3 11 pmol/L (3.1 – 6.8)

TSH <0.01 mU/L (0.3 – 4.2)

what’s the diagnosis?

Answer 31

primary hyperthyroidism

Question 32

what conditions can cause primary hyperthyroidism?

Answer 32

• graves - autoimmune
• plummer’s disease - toxic multi-nodular goitre or a singe adenoma/ hot nodule
• Inflammation of the thyroid - post-partum or viral
• Drug-induced

Question 33

On examination a patient with primary hyperparathyroidism had a fine tremor and looked thin. Her pulse was 112 beats per minute and her blood pressure 106 / 70 mmHg. Examining her neck, there was a mass in the centre of her neck, which was soft, extended symmetrically either side of the midline and was not tender to touch. This mass moved with swallowing. She had bilateral exophthalmos (prominent eyes).

What’s the diagnosis? Why?

Answer 33

grave’s disease

exopththalmos and smooth, symmetrical goitre

Question 34

What investigation could be used to confirm the cause of her hyperthyroidism?



Answer 34

Anti-TSH receptor antibody test

Radioactive iodine scan

Question 35

what is the first line of treatment for hyperthyroidism?

Answer 35

beta blockers and thionamides

Question 36

what is potassium iodide used for? How does it work and for how long?

Answer 36

preparation of hyperthyroid patients for surgery, turns everything off for 10 days due to iodine overload

also used in severe thyrotoxic crisis

Question 37

after 18 months of thionamides, what should the doctor do?

Answer 37

1. prescribe further thionamides and monitor

2. Radioiodine OR thyroidectomy

Question 38

give two examples of thionamides

Answer 38

propyl-thio uracil

carbimazole

Question 39

what precaution should you take if taking radioiodine?

Answer 39

avoid people for several days