Thyroid disease Flashcards
Thyroid function tests
TSH - tells you if problem is because of thyroid (primary) or secondary (pit/hyp)
FT4 - hypo or hyper
FT3
Thyroid autoantibodies
Anti-TPO AB - thyroid peroxidase autoantibody
TRAB TSH receptor autoantibody
best biomarker of thyroid status
TSH
What are the different types of thyroid autoantibodies?
Destructive - target thyroid for autoimmune destruction
Stimulatory - stimulate TSH receptor
Symptoms of hypothyroidism
lethargy mild weight gain cold intolerance constipation dry skin hair loss
Signs of hypothyroidism
puffy face pale periorbital oedema diffuse hair loss goitre croaky voice
What are causes of primary hypothyroidism?
thyroiditis autoimmune drugs hypo after treatment congenital
Primary hypothyroidism levels
raised TSH
reduced T4 /3
secondary hypothyroidism
Low TSH T3 T4
What is myxoedema ?
Accumulation of glycosaminoglycans in interstitial spaces of tissues
when thyroid hormones become very low causing symptoms of confusion, hypothermia and drowsiness
What are symptoms of thyrotoxicosis?
weight loss lack of energy heat intolerance anxiety thirst palpitations
sign of thyrotoxicosis
tremor warm moist skin tachycardia brisk reflexes thyroid bruit eye signs
What are symptoms of thyroid eye disease?
inflammation of all orbital tissues except the eye
fat, muscles, conjunctiva, eyelids
mild symptoms - itchy dry eyes, prominent eyes
worrisome symptoms - loss of sight, loss of colour vision, unable to close eyes fully, ache/pain/tightness in eye
sign associated with thyrotoxicosis
hands - fine tremor/warm
pulse - sinus tachycardia/atrial fibrillation
neck - goitre, move when swallow
eyes - lid retraction/proptosis
Causes of thyrotoxicosis?
Autoimmune hyperthyroidism (graves disease) autoantibody stimulates TSH receptor causing excess thyroid hormone production and thyroid growth (goitre).
toxic multinodular goitre
toxic adenoma
thyroiditis
drugs - amiodarone
gestational thyrotoxicosis
more likely in twin pregnancy
placental BHCG is structurally similar to TSH and similar action on the thyroid.
settles after 1st trimester
Graves disease treatment options
medical therapy - carbimazole o PTU rare side effect - agranulocytosis surgery - subtotal thyroidectomy symptom control - BB Radioactive iodine treatment I-131 radiation kills thyroid cells
Treatment for a toxic adenoma or toxic multinodular goitre
initially - short term medical treatment to control TFT
subsequent treatment - radioiodine
Treatment options for thyroid eye disease?
Encourage smoking cessation
steroids - prednisolone
radiotherapy
surgical treatment - orbital decompression/eye lid surgery
Thyroid storm
usually secondary to graves disease
triggered by childbirth, surgery, acute severe illness such as infection, trauma, diabetic ketoacidosis, stroke
What are the features of thyroid storm?
affects many systems
CNS - agitation/delirium
GI - nausea/vomiting/diarrhoea
Cardiovascular - tachy, atrial dysrhytmias, ventricular dysfunction, heart failure
Thyroiditis
Mild thyrotoxicosis that always resolves 1-2 months
longer hypothyroid phase 4-6 months
Who would you consider to test for thyroiditis?
pregnant, within 1 year post partum, increased risk T1D, smoker, tender thyroid
What other associations are there with autoimmune thyroid disease?
type 1 diabetes penicious anaemia coeliac disease premature ovarian failure addisons disease syndromes - turners and downs medications - lithium (inhibits thyroid hormone synthesis)
