Hyperthyroidism & Graves

Question 1

What is the definition of hyperthyroidism?

Answer 1

Clinical effect of excess thyroid hormone

Question 2

What is primary and secondary hyperthyroidism?

Answer 2

Primary - abnormal increased thyroid function
Secondary - abnormal increased TSH production (problem in hypothalamus or pituitary)

Question 3

What is thyrotoxicosis?

Answer 3

Increased thyroid hormone in body

Question 4

Epidemiology

Answer 4

Mainly young women (20-40)
Prevalence of 0.5%

Question 5

Causes of hyperthyroidism

Answer 5

Graves’ disease (65 - 75%)
Toxic multinodular goiter (TMG)
Toxic adenoma
De quervain’s thyroiditis
Drugs: amiodarone, iodine, lithium

Secondary causes= TSH secreting pituitary tumour

Question 6

What is Graves’ disease?

Answer 6

IgG autoantibodies
TSH receptor antibodies - mimic TSH, bind to receptors and stimulate TSH receptors in thyroid gland = increased thyroid hormone

Question 7

What is a toxic multinodular goitre?
What do they do?

Answer 7

Nodules secrete thyroid hormones (plummers disease)

Question 8

What is de quervains thyroiditis?
What happens to the thyroid levels?
What is the treatment for it?

Answer 8

Swollen, red, tender goitre post vial infection

Initially increase thyroid in blood then hypo

Aspirin, prednisone is very severe

Question 9

What do amiodarone and iodine cause?
What is this called?

Answer 9

Hyper/hypo thyroidism
Wolff-chaikoff effect

Question 10

Signs and symptoms of hyperthyroidism

Answer 10

Goitre (usually diffuse unless TMG)
Tachycardia
Heat intolerance
Diarrhoea
Weight loss
Hyperphagia
Anxiety/irritability
Oligomenorrhoea
Fatigue

Question 11

What are symptoms specific to graves?

Answer 11

Thyroid eye disease - eyelid retraction, pre orbital swelling , exophthalmos (bulging of eye ball due to inflammation and swelling & hypertrophy of tissue behind the eye)

Pre tibial myxoedema (deposits of mucin under skin, discolored waxy, reaction to tissue under skin to TSH receptor Ab)

Thyroid acropachy (triad of digital clubbing, soft tissue swelling, periosteal new bone formation)

Diffuse goitre

Question 12

What do you use to diagnose hyperthyroidism?

Answer 12

TFTs
Thyroid function tests

Question 13

What is the TFT going to show for?
1^ hyperthyroidism (graves)
2^ hyperthyroidism
Subclinical hypo
Subclinical hyper

Answer 13

Decreased TSH, increased T4

Increased TSH, increased T4

Increased TSH, T4

Decreased TSH, T4

Question 14

Treatment for hyperthyroidism

Answer 14

1. Carbimazole
2. Propylthiouracil
3. Radioiodine
4. Thyroidectomy

Question 15

What does carbimazole do and side effects?

Answer 15

Blocks synthesis of T4

Agranulocytosis - presents as sore throat

Question 16

What does propylthiouracil do?

Answer 16

Prevents T4 to T3 conversion

Question 17

What does radioiodine do?

Answer 17

Definitive treatment
Destroys excess thyroid tissue

Question 18

What else can be given to relieve symptoms?

Answer 18

Beta blockers
Propranolol
Tachycardia, anxiety, sweating, tremor

Question 19

What is a complication of hyperthyroidism?

Answer 19

Thyroid storm

Question 20

What is thyroid storm?
Symptoms

Answer 20

Rapid deterioration of thyrotoxicosis & increased T4
Acute, severe presentation

Systemic decompensation = AF, tachycardia, coma, hypertension, delirium

Question 21

Treatment for thyroid storm

Answer 21

Propylthiouracil and beta blockers (propranolol)