Hyperthyroidism

Question 1

1) What is hyperthyroidism?
2) What is thyrotoxicosis?
3) What is the commonest cause of hyperthyroidism?

Answer 1

1) Overproduction of the thyroid hormone by the thyroid gland
2) Excessive thyroid hormone in the body
3) Grave’s disease

Question 2

1) What is the problem in primary hyperparathyroidism?
2) What is the problem in secondary hyperparathyroidism?
3) Where is the problem in secondary hyperparathyroidism?

Answer 2

1) A thyroid pathology where the thyroid itself is producing excessive thyroid hormone
2) Thyroid is producing excessive thyroid hormone as a result of overstimulation by thyroid stimulating hormone
3) Hypothalamus or pituitary

Question 3

1) Is Grave’s disease a primary or a secondary hyperthyroidism?
2) What is the pathophysiology of hyperthyroidism?

Answer 3

1) Primary
2) Autoimmune condition where TSH receptor antibodies (abnormal antibodies that mimic TSH) stimulate the TSH receptors on the thyroid

Question 4

What is the pathophysiology of toxic multinodular goitre?

Answer 4

Nodules develop on the thyroid gland that act independently of the normal feedback system and continuously produce excessive thyroid hormone

Question 5

Name another cause of hyperthyroidism

Answer 5

• Solitary toxic thyroid nodule
• Causes of thyroiditis i.e. De Quervain’s, Hashimoto’s, postpartum and drug-induced thyroiditis

Question 6

Name 4 universal features of hyperthyroidism

Answer 6

• Anxiety and irritability
• Sweating and heat intolerance
• Tachycardia
• Weight loss
• Fatigue
• Frequent loose stools
• Sexual dysfunction

Question 7

1) Name 2 unique features of Grave’s disease
2) Why are these features unique to hyperthyroidism?
3) What is the greatest risk factor for developing thyroid eye disease in patients with Grave’s disease?

Answer 7

1) Diffuse goitre (without nodules), graves eye disease, bilateral exophthalmos, pretibial myxoedema
2) Presence of TSH antibodies
3) Smoking

Question 8

1) What is exophthalmos?
2) What causes it in Grave’s disease?
3) What is pretibial myxoedema?
4) How does it appear in Grave’s disease

Answer 8

1) Bulging forward of the eyeball out of the socket
2) Inflammation, swelling and hypertrophy of the tissue behind the eyeball that forces the eyeball forward
3) Deposits of mucin under the skin on the anterior aspect of the leg
4) Discoloured, waxy, oedematous appearance to the skin over this area

Question 9

1) What is the first line anti-thyroid drug?
2) What is the second line anti-thyroid drug?
3) Why is it second line (and not 1st)?

Answer 9

1) Carbimazole
2) Propylthiouracil
3) Small risk of severe hepatic reactions

Question 10

How does treatment with radioactive iodide work?

Answer 10

Drinking a single dose of iodide and it’s taken up by the thyroid gland and the emitted radiation destroys a proportion of the thyroid cells. The reduction in functioning cells results in a decrease of thyroid hormone production

Question 11

1) Why are beta blockers occasionally used in the management of hyperthyroidism?
2) Why is propranolol a suitable drug?

Answer 11

1) They block the adrenalin related symptoms of hyperthyroidism
2) It’s non-selective

Question 12

1) What is the definitive option for the treatment of hyperthyroidism?
2) If a patient undergoes this treatment option, what drug do they need to take for the rest of their lives?

Answer 12

1) Surgical removal
2) Levothyroxine