Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

BRS YR2 > Hyperthyroidism > Flashcards

Hyperthyroidism Flashcards

1
Q

What inhibits TRH and therefore TSH?

A

T4 and T3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is Graves’ disease?

A

Autoimmune
Antibodies bind and stimulate the TSH receptor in the thyroid
Causing a smooth goitre and hyperthyroidism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are common symptoms of Graves’ disease?

A

Exophthalmos

Pretibial myxoedema

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What causes exophthalmos in people with Graves’ disease?

A

Antibodies binding to the muscles behind the eye

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is pretibial myxoedema?

A 
The swelling (non-pitting) that occurs on the shins of patients with Graves' disease (growth of soft tissue)
associated with hyperthyroidism NOT hypothyroidism
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Describe the goitre caused by Graves’ disease.

A

Diffuse enlargement and engorgement of the thyroid gland

with uniform radioiodine uptake

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the difference between Plummer’s disease and Graves’ disease?

A

Plummers is:

  • not autoimmune
  • no pretibial myxoedema
  • no exophthalmos
  • non-symmetrical and non-diffuse goitre
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is Plummer’s disease?

A

Characterised by:

  • toxic nodular goitre
  • benign adenoma (overactive) produces excess thyroxine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How does thyroxine impact the sympathetic nervous system?

A

It sensitises beta adrenoreceptors to the ambient levels of adrenaline and noradrenaline - causing apparent sympathetic activation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How does the impact of thyroxine on the sympathetic nervous system present?

A
  • tachycardia
  • palpitations
  • tremor in the hands
  • lid lag
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the symptoms of hyperthyroidism?

A
  • weight loss (despite increased appetite)
  • breathlessness
  • palpitations
  • tachycardia
  • sweating
  • heat intolerance
  • diarrhoea
  • lid lag (+ other sympathetic features)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is a thyroid storm?

A

A medical emergency resulting in a 50% mortality if untreated
(aggressive treatment is required)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the characteristics of a thyroid strom?

A
  • Hyperpyrexia (>41)
  • accelerated tachycardia/arrhythmia
  • cardiac failure
  • delirium/frank psychosis
  • hepatocellular dysfunction; jaundice
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the possible treatments for hyperthyroidism?

A
  • surgery (thyroidectomy)
  • radioiodine
  • drugs
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the 4 classes of drugs involved in the treatment of hyperthyroidism?

A 
Thionamides (thiourylenes; anti-thyroid drugs)
- propylthiouracil (PTU)
- carbimazole (CBZ)
Potassium Iodide
Radioiodine
Beta-Blockers
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the aim of thionamides, potassium iodide and radioiodine?

A

To reduce thyroid hormone synthesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the aim of Beta-blockers?

A

To help with the symptoms associated with hyperthyroidism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the 2 main hormones involves in thyroid hormone synthesis?

A
  • Thyroperoxidase

- Peroxidase transaminase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the mechanism of action of thionamides?

A

The inhibition of thyroid peroxidase and therefore T3/4 synthesis and secretion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How long does it take for thionamides to come into effect?

A

biochemical effect: hours

clinical effect: weeks

21
Q

What drug often accompanies thionamides in a treatment plan?

A

Propanolol (beta-blockers)

rapidly reduces tremors, and tachycardia

22
Q

Describe the synthesis of thyroid hormones

A
  • Uptake of iodide via active transport
  • Iodination
  • Coupling reaction: storage in the colloid
  • Endocytosis and secretion
23
Q

What are the symptoms of hyperthyroidism?

A
  • weight loss (despite increased appetite)
  • breathlessness
  • palpitations
  • tachycardia
  • sweating
  • heat intolerance
  • diarrhoea
  • lid lag (+ other sympathetic features)
24
Q

What is a thyroid storm?

A

A medical emergency resulting in a 50% mortality if untreated
(aggressive treatment is required)

25
Q

What are the characteristics of a thyroid strom?

A
  • Hyperpyrexia (>41)
  • accelerated tachycardia/arrhythmia
  • cardiac failure
  • delirium/frank psychosis
  • hepatocellular dysfunction; jaundice
26
Q

What are the possible treatments for hyperthyroidism?

A
  • surgery (thyroidectomy)
  • radioiodine
  • drugs
27
Q

What are the 4 classes of drugs involved in the treatment of hyperthyroidism?

A 
Thionamides (thiourylenes; anti-thyroid drugs)
- propylthiouracil (PTU)
- carbimazole (CBZ)
Potassium Iodide
Radioiodine
Beta-Blockers
28
Q

What is the aim of thionamides, potassium iodide and radioiodine?

A

To reduce thyroid hormone synthesis

29
Q

What is the aim of Beta-blockers?

A

To help with the symptoms associated with hyperthyroidism

30
Q

What are the 2 main hormones involves in thyroid hormone synthesis?

A
  • Thyroperoxidase

- Peroxidase transaminase

31
Q

What is the mechanism of action of thionamides?

A

The inhibition of thyroid peroxidase and therefore T3/4 synthesis and secretion

32
Q

When is radioiodine contrindicated?

A

Pregnancy

33
Q

What drug often accompanies thionamides in a treatment plan?

A

Propanolol

rapidly reduces tremors, and tachycardia

34
Q

Describe the synthesis of thyroid hormones

A
  • Uptake of iodide via active transport
  • Iodination
  • Coupling reaction: storage in the colloid
  • Endocytosis and secretion
35
Q

What are the unwanted actions of thionamides?

A
  • rashes (common)

- Agranulocytosis (normally a reduction in neutrophils) - rare, and reversible by stopping the drug

36
Q

How to follow up on the patient using drugs to treat hyperthyroidism?

A
  • aim to stop the anti-thyroid drug treatment after 18 months
  • review patient periodically, including thyroid function tests for remission/relapse.
37
Q

Why are beta-blockers like propanolol involved in treatment plans with anti-thhyroid drugs?

A

Anti-thyroid drugs take several weeks to have clinical effects, therefore non-selective beta-blockers do so in the interim.

38
Q

When is potassium iodide used?

A
  • in preparation for surgery
  • during a thyroid storm (severe thyrotoxic crisis)
    usually in doses >30x daily requirement
39
Q

What is the mechanism of action of potassium iodide?

A
  • Inhibits the iodination of thyroglobulin

- Inhibits hydrogen peroxide generation and thyroperoxidase

40
Q

What is the impact of potassium iodide in hyperthyroidism?

A
  • inhibition of thyroid hormone synthesis and secretion
  • Wolff-Chaikoff effect
  • hyperthyroid symptoms reduce in 1-2 days
  • vascularity and size of the gland reduce in 10-14 days
41
Q

What is the Wolff-Chaikoff effect?

A

A presumed auto-regulatory effect

42
Q

What are the risks involved in surgery/thyroidectomy?

A
  • risk of voice change
  • risk of parathyroid gland loss
  • scarring
  • risk involved in anaesthesia
43
Q

What is the process involved in radioiodine?

A
  • swallow a capsule containing 370MBq (10mCi) of the isotope I (131)
  • need to avoid children and pregnant mums for a few days
  • for scans ONLY: 99-Tc pertechnetate is an option
44
Q

When is radioiodine contrindicated?

A
  • pregnancy
45
Q

What are the symptoms of Viral (de Quervain’s) thyroiditis?

A
  • painful dysphagia
  • hyperthyroidism
  • pyrexia
  • thyroid inflammation
  • one-sided visible enlargement of the thyroid gland
46
Q

What causes Viral (de Quervain’s) thyroiditis?

A
  • virus attacks the thyroid gland causing pain and tenderness
  • thyroid stops making thyroxine and makes viruses instead
  • therefore no iodine uptake (ZERO)
  • stored thyroxine is released
  • thus, toxic with 0 reuptake
  • 4 weeks later, stores are exhausted > hypothyroidism
  • 8 weeks later, resolution occurs
  • patient becomes euthyroid
47
Q

How does Viral (de Quervain’s) thyroiditis present?

A
  • painful neck
  • all stored thyroxine is released
  • fT4 levels rise
  • TSH levels drop
  • 1 month of hyperthyroidism
  • no new thyroxine synthesis
  • fT4 slowly falls
  • patients becomes hypothyroid (thyroid just replicates the virus)
    lasts another month
  • after 3 months, slow recovery
48
Q

What is the difference between viral (de Quervain’s) thyroiditis and postpartum thyroiditis?

A

postpartum thyroiditis has no pain, and only occurs post pregnancy

BRS YR2 (70 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions