Thyroid Pathology

Question 1

What is Thyrotoxicosis

Answer 1

• AKA hyperthryoidism

- Increased levels of circulating free thyroid hormone

Question 2

What are the three main causes of Thyrotoxicosis

Answer 2

• Grave’s disease (75%)
• Toxic multinodular goitre (15%)
• Toxic Adenoma (5%)

Question 3

What are the other causes of Thyrotoxicosis (not main 3)

Answer 3

• Hashimoto’s thyroiditis
• Post-partum hyperthyroidism
• Viral (De Quervain’s)
• Drugs (e.g. amiodarone)

Question 4

What are the clinical features of Thyrotoxicosis

Answer 4

CHAMPS

• Diarrhoea, hair loss
• Increased appetite, weight loss
• Oligo/amenorrhoea
• Heat intolerance
• Sweaty skin

Other

• Lid lag
• Clubbing
• Proximal myopathy
• Tachycardia/Atrial fibrillation

Question 5

What are the additional clinical features of Graves’ disease

Answer 5

Eye disease

• Exophthalmos
• Proptosis

Other
- Pretibial myxoedema

Question 6

What are the pathophysiologies of each cause of Thyrotoxicosis

Answer 6

• Graves’: autoimmune anti-TSH receptor antibodies
• Toxic multinodular: mutliple Thyroid secreting nodules
• Toxic adenoma: single thyroid secreting nodule
• Hashimotos: autoimmune anit-TPO antibodies

Question 7

What are the investigations for Thyrotoxicosis

Answer 7

TFTs

• Increased T3/T4
• TSH: Decreased (primary), Increased/normal (secondary)

Autoimmune screen

• Anti-TSH receptor antibodies (Graves’)
• Anti-TPO antibodies (Hashimotos)

Thyroid uptake scan

Question 8

What are the Thyroid uptake scan results for different causes of Thyrotoxicosis

Answer 8

• Graves: global increased uptake
• Toxic multinodular: pathcy increased uptake
• Toxic adenoma: single hot spot of increased uptake

Question 9

What is the management of Thyrotoxicosis

Answer 9

First line

• Medication: carbimazole
• Radioactive iodine (have to stop anti-thryoid drugs a week before)

Second line: Surgery

• Thyroidectomy (partial or total)
• Complications: hoarse voice, hypo-thyroidism/parathyroidism