Thyrotoxicosis

Question 1

What are the symptoms of thyrotoxicosis?

Answer 1

Diarrhoea, weight loss, increased appetite, labile emotions, oligomenorrhoea +/- infertility, heat intolerance, sweats, palpitations, tremors, irritability, overactive

Rare: psychosis, urticaria, Alopecia, chorea, itch

Question 2

What are the signs of thyrotoxicosis?

Answer 2

Lid retraction, lid lag
Fast/irregular heart rate (AF, SVT)
Fine tremor
Warm, moist skin
May have goitre, thyroid nodules
May have bruit

Question 3

What are the 3 signs of thyrotoxicosis?

Answer 3

Eye disease - exophthalmos, ophthalmoplegia
Pretibial myxoedema
Thyroid acropachy

Question 4

What are the causes of thyrotoxicosis?

Answer 4

Graves’ disease 2/3
Toxic multinodular goitre
Toxic adenoma 
Ectopic thyroid tissue
Exogenous - iodine excess (food contamination, contrast media), levothyroxine excess

Question 5

What is Graves’ disease?

Answer 5

More common in women, 40s-60s
Autoimmune
Triggers: stress, infection, child-birth

Question 6

What is a toxic multinodular goitre and when is surgery indicated?

Answer 6

Seen in the elderly and iodine deficient areas
Nodules secrete thyroid hormones
Surgery indicated for compressive symptoms from the enlarged thyroid gland - dysphasia, dyspnoea

Question 7

What is a toxic adenoma?

Answer 7

A solitary module producing thyroid hormones
The nodule is hot on an isotope scan and the rest of the gland is suppressed

Question 8

What are the tests used in thyrotoxicosis?

Answer 8

TSH (low), T4, T3 (high)
May be mild anaemia and neutropenia in Graves
Raised ESR
Raised calcium
Raised LFTs
Check thyroid autoantibodies
Isotope scan (if cause unclear) - nodular disease
Visual fields, acuity and eye movements if ophthalmopathy

Question 9

What is the treatment for thyrotoxicosis?

Answer 9

Drugs

• beat blockers (rapid symptom control)
• carbimazole, reducing dose every 1-2 months according to TFTs
• OR carbimazole and levothyroxine simultaneously (reduces risk of iatrogenic hypothyroidism)

Radioiodine

• most become hypothyroid post-treatment
• careful in active hyperthyroidism as thyroid storm
• CI: pregnancy and lactation

Thyroidectomy

• risk of damage to the recurrent laryngeal nerve and hypoparathyroidism
• become hypo after

Question 10

What are the complications of thyrotoxicosis?

Answer 10

Heart failure, angina, AF, osteoporosis, ophthalmopathy, gynaecomastia, thyroid storm