Hyperthyroidism

Question 1

What is thyrotoxicosis?

Answer 1

The clinical effect of excess thyroid hormone, usually from hyper function of the gland

Question 2

What are the main causes of hyperthyroidism?

Answer 2

1. GRAVES’ DISEASE (2/3) - IgG autoantibodies bind to receptors causing thyroid enlargement and increased hormone production
2. TOXIC MULTINODULAR GOITRE - seen in the elderly and iodine-deficient areas, formation of thyroid-secreting nodules
3. TOXIC ADENOMA - solitary nodule producing T3+T4

Question 3

How does hyperthyroidism present?

Answer 3

-Diarrhoea
-Weight loss, increased appetite
-Over-activity
-Sweats
-Heat intolerance
-Palpitations, tremor
-Irritability, emotional lability
-Oligomenorrhoea +/- infertility

Question 4

What signs might a patient with hyperthyroidism have?

Answer 4

-Irregular / fast pulse
-Fine tremor
-Palmar erythema
-Goitre, thyroid nodules
-Lid lag / retraction / exophthalmos (thyroid eye disease)

Question 5

What are the 3 key signs of Graves’ disease?

Answer 5

1. Eye disease (exophthalmos, ophthalmoplegia)
2. Pretibial myxoedema
3. Thyroid acrophacy (clubbing, painful finger and toe swellings)

Question 6

How would you investigate someone with hyperthyroidism?

Answer 6

-TFTs (low TSH, raised T3)
-FBCs (Graves’ may cause anaemia / neutropenia)
-Raised LFTs
-Thyroid autoantibodies
-Isotope scan if cause is unclear
-Test visual fields / acuity / eye movements if eye disease is present

Question 7

How would you treat hyperthyroidism?

Answer 7

DRUGS
-beta blockers (symptom control)
-carbimazole (20-40mg)
-carbimazole + levothyroxine
RADIOIODINE
-most become hypothyroid so require levothyroxine
THYROIDECTOMY