Thyrotoxicosis

Question 1

what is thyrotoxicosis?

Answer 1

the clinical effect of ↑T4, usually from gland

hyperfunction.

Question 2

symptoms of thyrotoxicosis

Answer 2

• Diarrhoea
• ↑ appetite but ↓ wt.
• Sweats, heat intolerance
• Palpitations
• Tremor
• Irritability
• Oligomenorrhoea ± infertility

Question 3

signs of thyrotoxicosis in the hands

Answer 3

• Fast / irregular pulse
• Warm, moist skin
• Fine tremor
• Palmer erythema

Question 4

signs of thyrotoxicosis in the face

Answer 4

• thin hair
• lid lag
• lid retraction

Question 5

signs of thyrotoxicosis in the neck

Answer 5

goitre or nodules

Question 6

signs specific to Graves

Answer 6

1. Ophthalmopathy
   - Exophthalmos
   - Ophthalmoplegia: esp. up-gaze palsy
   - Eye discomfort and grittiness
   - Photophobia and ↓ acuity
   - Chemosis
2. Dermopathy: pre-tibial myxoedema
3. Thyroid acropachy

Question 7

investigations in thyrotoxicosis

Answer 7

Bloods:
-↓TSH, ↑T4/↑T3
- Antibodies: TSH receptor, TPO
- ↑Ca, ↑LFTs
Isotope scan
- ↑ in Graves’
- ↓ in thyroiditis
Ophthalmopathy: acuity, fields, movements

Question 8

most common cause of thyrotoxicosis?

Answer 8

Graves disease

Question 9

triggers of Graves disease

Answer 9

• stress
• infection
• child-birth

Question 10

conditions associated to Graves disease

Answer 10

• type 1 diabetes mellitus
• vitiligo
• Addison’s

Question 11

other causes of thyrotoxicosis

Answer 11

• toxic multinodular goitre (Plummer’s disease)
• toxic adenoma
• thyrotoxic phase of thyroiditis (Hashimoto’s, de Quervain’s, subacute lymphocyctic)
• drugs (thyroxine, amiodarone)

Question 12

medical treatment for thyrotoxicosis

Answer 12

1. Symptomatic: β-B (e.g. propranolol 40mg/6h)
2. Anti-thyroid: carbimazole (inhibits TPO)
   - Titrate according to TFTs or block and replace
   - In Graves’ Rx for 12-18mo then withdraw
   (~50% relapse → surgery or radioiodine)
   - SE: agranulocytosis

Question 13

radiological treatment for thyrotoxicosis

Answer 13

radio-iodine

• most become hypothyroid
• contraindicated in pregnancy and lactation

Question 14

surgical treatment for thyrotoxicosis

Answer 14

thyroidectomy

• recurrent laryngeal nerve damage → hoarseness
• hypoparathyroidism
• hypothyroidism

Question 15

what is a thyroid storm?

Answer 15

thyrotoxic crisis
- acute, life-threatening, hypermetabolic state induced by excessive release of thyroid hormones (THs) in individuals with thyrotoxicosis.

Question 16

clinical features of thyroid storm

Answer 16

• ↑ temp
• Agitation, confusion, coma
• Tachycardia, AF
• Acute abdomen
• Heart failure

Question 17

precipitants to thyroid storm

Answer 17

• Recent thyroid surgery or radio-iodine
• Infection
• MI
• Trauma

Question 18

treatment for thyroid storm

Answer 18

1. Fluid resuscitation + NGT
2. Bloods: TFTs + cultures if infection suspected
3. Propranolol PO/IV
4. Digoxin may be needed
5. Carbimazole then Lugol’s Iodine 4h later to inhibit thyroid
6. Hydrocortisone
7. Rx cause