day 2 Flashcards
what cells are round the outside of colloid
follicular
what levels can discriminate between hyper, hypo and euthydroidism
TSH levels
exceptions of when low TSH and low/normal T3 and T4
hypopituitarism
tests for hyperthyroidism
TSH plus free T4 or T3
tests for hypothyroidism
TSH plus serum free T4
what levels are greatly increased in pregnancy
TBG and total T4 but free T4 is normal.
what does amiodarone do
decrease t4 to t3 conversion and so t4 level may be higher than expected
what antibodies are specific for graves
TSH receptor IgG antibodies
what is the most common hypothyroidism
atrophic
what autoimmune thyroiditis leads to goitre formation
Hashimotos thyroiditis
what may cause hyperthyroidism, hypothyroidism or the 2 sequentially
post partum thyroiditis
post partum thyroididits has a high chance of proceeding to permanent
hypothyroidism
what is the mechanism of goitre
borderline hypothyroidism leading to TSH stimulation and thyroid enlargement in the face of continuing iodine deficiency
specific signs of hypothyroidism
dry thin hair, bradycardia, dry skin, slow relaxing reflexes
slow, dry haired, thick skinned, deep voiced, weight gain, cold intolerance, bradycardia and constipation is a classic picture of
hypothyroidism
what confirms primary hypothyroidism
high TSH levels with low T4
why should complete suppression of TSH be avoided
risk of atrial fib and osteoporosis
pregnant woman should have optimal replacement as mothers with elevated TSH during pregnancy can result in kids with
reduction in cognitive function
severe hypothyroidism may present with
confusion or even coma
what mental health illness is common in hypothyroidism
depression
nearly all cases of hyperthyroidism are caused by
intrinsic thyroid disease
most common cause of hyperthyroidism
graves disease
what condition produces antibodies that pretend to be TSH
graves
signs of thyrotoxicosis, diffuse goitre and extra thyroidal manifestations eg opthalmopathy
graves
signs of thyrotoxicosis, palpable solitary nodule or multinodualr goitre
solitary multinodular thyrotoxicosis
signs of thyrotoxicosis, diffuse goitre and tender on palpation
thyroiditis
specific signs of hyperthyroidism
tremor, hyperkinesis (excessive restlessness), tachycardia or atrial fibrillation, full pulse, warm vasodilator peripheries, exophthalmus( bulging eyes), lid lag and stare (upper eyelid retraction), goitre bruit
what is transient hyperthyroidism from an acute inflammatory process, probably viral in orgin
de quervains thyroiditis
what may flow after de quervains thyroiditis after a few weeks
hypothyroidism
what may flow after de quervains thyroiditis after a few weeks
hypothyroidism
treatment of de quervains thyroiditis
acute phase - aspirin
short term in severely symptomatic - prendisolone
what drug has high iodine content
amiodarone
some cancer drugs eg ipilimumab can cause
thyroiditis
what is infiltration. of the skin on the shin
pretibial myxoedema
frequently present with atrial fib is common in elderly in
hyperthyroidism/ graves - not sure which one
children with excessive height, weight gain and hyperactivity have
hyperthyroidism
very useful clinical symptom of hyperthyroidism
weight loss despite normal appetite
signs that differentiate hyperthyroidism from anxiety
eye signs, diffuse goitre, proximal myopathy and wasting
what confirms the diagnosis fo hyperthyroidism
serum TSH is suppressed and raised free T3 or T4
antibodies seen in graves
TSH receptor stimulating antibodies and thyroid peroxidase antibodies (TPO)
Tsh is 97-99% specific for graves
TPO are present in80% of graves but are also found in normal individuals
most used anti thyroid drug in UK
carbimazole
what is another option that is also an antithyroid drug
propylthiouracil
how long does it take for anti thyroid drugs. to work
10-20 days
what drug can provide symptomatic control in hyperthyroidism
beta blockers eg propanolol
what % of patients relapse after a course of carbimazole or propylthiouracil within the following 2 years
50
side effects of carbimazole
angranuclocytosis
may develop sore throat or unexplained fever and should have white blood cell counted
when is radioactive iodine contraindicated
pregnancy and while breast feeding
patients should not be on antithyroid drugs when on
radio iodine
is there increased risk of malignancy after radioactive iodine
no
some drugs given in thyroid storm
propranolol immediately, potassium iodide, antithyroid drugs, corticosteroids
what is the preferred antithyroid drug at conception and during first trimester
propythiouracil
why is propythiouracil given during conception and first trimester in hyperthyroidism
due to rare reports of congenital abnormalities
why is carbimazole recommended during 2 and 3 trimester
as liver problems more frequently described on PTU
high levels of HCG found in pregnancy causes what to TSH receptor and t3 and t4
suppressed TSH with slightly elevated T3/4
if a mother has ever had graves she may still have circulating thyroid stimulating immunoglobulin and so
may stimulate metal thyroid and so foetus can become hyperthyroid
what do you measure in foetus for thyroid status
foetal heart rate
thyroid hormone resistance is an – condition
inherited
what is mutated and abnormal in thyroid hormone resistance
thyroid hormone receptor
thryroid hormone resistance is diagnosed on basis of
raised t3/4 and normal TSH
long term risk of hyperthyroidism may cause
osteoporosis and atrial fib which may predispose to thromboembolic disease
graves orbitopathy can cause swelling and oedema of the muscles around the eye leading to
limitation of movement and proptosis
proptosis and lid retraction in graves may limit the ability to
close eyes completely
is goitre physiological or pathological
can be either
excessive doses of what will induce goitre
carbimazole or PTU
what Amy produce a diffuse increase in size of the thyroid
puberty and pregnancy
goitre which is smooth and soft and may be associated with thyroid growth stimulating antibodies
simple goitre
what 2 diseases are associated with firm diffuse goitre of variable size
Hashimoto’s thyroididits and graves disease thyrotoxicosis
when is a bruit in a goitre often present
thyrotoxicosis
