FN: Hypothyroidism Flashcards
1
Q
Epi
A
4/1000/yr
Sex: F»M = 6:1
Age: >40yrs
2
Q
Symptoms
A
Letheragy Cold intolerance reduced appetite and weight ain constipation Menorrhagia reduced mood
3
Q
Signs
A
Cold hands Bradycardic Slow-relaxing reflexes Dry hair and skin Puffy face Goitre Myo[athy, neruopathy Ascites Myxoedema 1. SC tissue swelling in severe hypothyroidism 2. Typically around eyes and dorsum of hand
4
Q
Causes
A
Primary
Post surgical
Secondary
5
Q
Primary causes
A
Atrophic thyroiditis (commonest UK) Hasimoto's thyroiditis Subacute thyroiditis (e.g. post-partum) Post De Quervains thyroiditis Iodine deficiency (commonest worldside) Drugs: carbimazole, amiodarone, lithium Congenital: thyroid agenesis
6
Q
Post-surgical
A
thyroidectomy
Radioioding
7
Q
Secondary
A
Hypopituitarism (v.rare cause)
8
Q
Atrophic thyroiditis
A
- Thyroid antibodies +ve: anti-TPO, anti-TSH
- Lymphoctic infiltrate –> atrophy (no goitre)
- Associations
9
Q
Atrophic thyroiditis associatinos
A
Pernicious anaemia
Vitiligo
Endocrinopathies
10
Q
Hasimotos thyroiditis
A
TOP +ve
Atrophy + regeneration –> goitre
May go through initial thyrotoxicosis phase
May be euthyroid or hypothyroid
11
Q
Investigations
A
- Raised TSH, reduced T3/T3
- Raised MCV ± normochromic anaemia
- raised triglyceride + raised cholesterol
- Hyponatraemia (SIADH)
- raised CK if assoc. myopathy
- Abs: TPO, TSH
12
Q
Treatment
A
Levothyroxine
- titrate to normalise TSH
- Enzyme inducers raised thyroxine metabolism
- Clinical improvement takes - 2wks
Check for other AI disease e.g. addison’s PA
13
Q
Myxoedema Coma features
A
looks hypothyroid Hypothermia Hypoglycaemia HEart failure: bradycardia and reduced BP Coma and seizures
14
Q
Myxoedema Coma precipitants
A
- radioiodine
- Thyroidectomy
- Pituitary surgery
- Infection, trauma, MI, stroke
15
Q
Myxoedema Coma management
A
Bloods: TFTs, FBC, U+E, glucose, cortisol
Correct any hypoglycaemia
T3T4 IV slowly (may ppt. myocardial ischaemia)
Hydrocortisone 100mg IV
Treat hypothermia and heart failure
