Pathology of the Thyroid I Flashcards
thyroid axis
hypothalamus - TRH
anterior pituitary - TSH
thyroid - T3 and T4
T3 and T4 negative feedback on hypothalamus and anterior pituitary
TSH receptor - GPCR
42yo F sweating, pounding heart, weight loss, enlarged nontender thyroid, wide eye gaze
hyperthyroidism
eye protrusion in graves
accumulation of loose CT behind eyeballs
thyroid function testing
serum TSH and T4
ultrasound/radionucleotide uptake studies
serum Abs
low TSH and high T4
hyperthyroid
high TSH and low T4
hypothyroid
normal thyroid
euthyroid
ultrasound of thyroid
tells you cystic vs. solid
toxic
hyperfunctioning
elevated T3 and T4
thyrotoxicosis
-hypermetabolic state
majority of hyperthyroid
graves disease
diffuse hyperplasia of thyroid
also caused by multinodular goiter and thyroid adenoma
3 most common causes of thyrotoxicosis
graves disease**
multinodular goiter
thyroid adenoma
T4 vs. T3
T3 higher activity
T4 higher levels (10:1)
overactive sympathetics
with hyperthyroidism
increased metabolism, heat intolerance, weight loss with increased appeitite, tachycardia, palpitations, cardiomegaly, anxiety, insomnia
hyperthyroidism
early manifestations of hyperthyroidism
cardiac manifestations
tachy, palps, cardiomegaly
also atrial fib possible
complication - CHF
low output heart failure
thyrotoxic cardiomyopathy
reversible left ventricular dysfunction
individuals with hyperthyroidism
GI and hyperthyroid
hypermotility, diarrhea, malabsorption
lid lag
seen with hyperthyroid
-due to sympathetic overstiulation of mullers muscle (superior tarsal m)
proptosis
graves disease
protrusion of eyeballs
skeletal system and hyperthyroid
thyroid hormone - stimulates osteoporosis and increased fracture risk
sudden onset of severe hyperthyroid
thyroid storm
patient with graves disease and sudden increase in stress on body (infection, surgery,, etc.)
febrile and tachycardia
complication - untreated patient can die due to cardiac arrhythmias
women with hypothyroid
don’t overtreat - can lead to osteoporosis
teratoma
commonly has thyroid tissue as well**
exopthalmos
graves disease
rash on front of shins
pretibial myxedema
-seen in graves disease