Hyperthyroidism (Thyrotoxicosis) Flashcards
HYPERthyroidism = HYPER symptoms
1) what symptom combo are patients particularly confused about?
2) what happens in terms of muscle weakness?
3) name some features
1) ^^weight loss + ^appetite
2) proximal muscle weakness - ‘can’t stand up from the chair’, ‘brushing hair’, ‘beans in cupboard’
3) diarrhoea, heat intolerance, sweaty, palpitations (neuro - tremor, anxiety, restless, brisk reflexes)
signs of hyperthyroidism on examination?
signs of graves’ disease in hyperthyroidism?
fine tremor
irregular/fast pulse (AF)
lid retraction (staring appearance)
may be a goitre
1) thyroid eye disease
2) pretibial myxoedema (swellings above lateral malleoli)
3) thyroid acropachy (clubbing, painful finger)
what do you often find in the following lab results with regards to hyperthyroidism?
1) TSH
2) T3/4
3) ESR
4) LFT
1) LOW
2) HIGH but T4 may not always be high but T3 will always be
3) high
4) high
would you choose radio-isotope Xray + US over CT when imaging hyperthyroidism?
yes
most common cause of hyperthyroidism?
graves’ disease
what is the F:M ratio in graves’ and hashimoto’s (also in all autoimmune conditions)
10/9:1 F:M
pathophysiology of graves’ disease
think G for graves’
circulating IgG autoantibodies
–>
activating G protein coupled thyrotropin receptors
–>
smooth thyroid enlargement + hormone production
second most common cause of hyperthyroidism?
difference between the two?
toxic multinodular goitre + toxic adenoma
toxic multinodular goitre
- seen in elderly
- multiple benign nodules secreting hormones
- surgery is indicated for compressive symptoms (dysphagia/dyspnoea) from goitre
toxic adenoma
- singular benign nodule producing T3/T4
- on isotope scan this is hot
what drug can cause both hypo and hyperthyroidism?
explain how each is caused by the drug?
Amiodarone (iodine rich drug structurally similar to T4)
hypothyroisim can be caused by iodine toxicity inhibiting T4
hyperthyroidism can be caused by destructive thyroiditis.
is thyroid eye disease specific to Graves’?
main RF for thyroid eye disease?
YES
seen in 25-50% of Graves’ pts.
Smoking
Explain the following signs of thyroid eye disease?
Exophthalmos
Proptosis
Diplopia
what is lost first before blindness
exopthalmos - protruding of the eye
Proptosis - eyes protude beyond orbit
Diplopia - blurred vision
colour vision is lost first
what is the Tx for thyroid eye disease?
Tx underlying hyperthyroidism
Elevate bed to reduce oedema
Severe: high dose steroids (IV methylprednisolone)
Tx of Hyperthyroidism
1) first drug you’d give to relieve symptoms?
2) a) antithyroid medication can be given in two ways: explain?
b) what are the SE of this antithyroid medication?
c) how long are they on antithyroid medication?
d) BUT if they have Graves’ disease what is the regimen?
e) what % of graves’ patients will relapse?
1) Beta-blocker (propanolol - short acting)
2) a) Titrated - carbimazole - then increase/decrease dose by routinely checking TFTs to ensure they don’t become hypothyroid.
Block Replace (carbimazole + levothyroxine) to reduce risk of hypothyroidism.
b) Carbimazole SE: agranulocytosis (no WBC) - Risk of sepsis and infection
c) 4 weeks
d) continue on antithyroid for 12-18 months.
e) 50%
Tx of Hyperthyroidism (cont’d)
3) a) if B-blocker and antithyroid med has been attempted, what is next?
b) how is it given?
c) risk of?
d) if pregnant - what are the rules?
4) a) surgery options?
b) risk of damage to which nerve?
c) what medication will they be on for life and why?
3) a) Radioiodine
b) tablet
c) risk of hypothyroidism
d) contraindicated and if thinking about pregnancy - can’t get pregnant for 6 months
4) a) thyroidectomy
b) recurrent laryngeal nerve - hoarse voice
c) thyroid replacement therapy for life as they will be hypothyroid
complications of hyperthyroidism?
HF
Angina
AF
Osteoporosis
