Define hypothyroidism
this is defined as an underachieve thyroid gland leading to deficiency of thyroid hormones
define Myxoedema
when hypothyroidism becomes symptomatic
What are the key things that hypothyroidism causes
- Cold intolerance
- Have a low metabolism
- decreased cognitive function
What are some of the features of hypothyroidism
- Peaches and cream complexion
- Loss of outer 1/3 of the eyebrow
- Bradycaria
- neuropathy and myopathy
- costipation
- Slow relaxation on reflexes
What are the features of myxodema
in severe hypothyroidism you get swelling of the subcutaneous tissues = bunch of banana hands
What are some of the key causes of hypothyroidism
In developing countries = iodine deficienc
in developed countries - hashimotos thryoditis
also
- ineffective (subacute thyroiditis - chronic is de quirvans)
- post thyroidectomy
- Drugs (amiodarone, lithium)
- Tumour
What are some of the secondary causes of hypothyroidism
- Hypopituitism
- Hypothalamic disorders
Investigations in hypothyroidism
Bloods:
- FBC
- TFTs
- TPO antibodies (increased in hashimotos)
- LFTs (can be raised)
- CK (raised due to myopathy)
How is hypothyroidism diagnosed
TFTs (have a very low threshold for doing these as complications include heart disease and dementia)
in what forms of hypothyroidism do you get a goitre and do you not get a goitre
Goitre:
- Hashimotos
No Goitre
- Autoimune
Treatment of hypothyroidism
young: lifetime treatment with levothyroxine 500mg daily (dose changes at 6 weeks)
Elderly: start on 25mg of levothyroxine and increase at 25mg intervals
you want to normalise but not surprise TSH so aim for >0.5
