Thyroid Flashcards
what is the thyroid
a 2 in butterfly shaped gland in the neck
secretes t3 and t4
iodine is a ______ component in the _____ of ________ hormone
necessary, synthesis, thyroid
negative feedback loop for thyroid
hypothalamus (releasing hormone TRH) anterior pituitary (releasing TSH) thyroid gland thyroxine then back to hypothalamus OR anterior pituitary T4 is released the most
two types of thyroid dysfunctions
hypothyroidism and hyperthyroidism
which type of thyroid disorder is most common?
primary
what is primary thyroid disorder?
involves the gland itself
thyroid problems are most common in?
women
an enlargement can occur in which thyroid disorders?
hypo and hyper
what is a goiter
enlargement of thyroid gland with or without thyroid dysfunction
what causes goiters?
excessive pituitary TSH
low iodine levels (decreased TSH manufacturing)
what are goitrogens?
foods or substances that promote thyroid gland enlargement
goitrogens promote thyroid gland enlargement
Ex: Lithium
which type of goiters are larger?
iodine deficient
what is hypothyroidism?
insufficient levels of T3 and T4
2 types primary and secondary
what is primary hypothyroidsim?
increase in release of TSH from pituitary
decrease in thyroid level
release of TSH indicates a hypoactive thyroid
low hormone secretion by thyroid gland, constantly signals pituitary to secrete TSH
what is secondary hypothyroidism?
pituitary not secreting TSH, T3 and T4
all 3 low
hashimotos thyroiditis
autoimmune
most common cause of hypothyroidism
increased TSH
decreased T3 and T4
what is the hallmark of hashimotos?
antithyroperoxidase antibody
what specific antibodies do you look for in hashimotos?
thyroid receptor antibodies
antithyroglobin antibody
antithyroperoxidase antibody
these antibodies attack the thyroid
risk factors for hashimotos
female older than 50 Caucasian pregnancy hx autoimmune dx family hx meds treatment for hyerthyroidism
why can treatment for hyperthyroidism cause hashimotos?
tx goes to far and ends up low, ex: radiation to the neck damaging thyroid
early manifestations of hypothyroidism
cold intolerance weight gain fatigue poor attention/memory probs high cholesterol yellow skin (carotene) hair loss puffy face brittle nails
late manifestations of hypothyroidism
below normal temp bradycardia THICK skin cardiac problems weight gain decreased LOC
hypothyroidism causes
raised cholesterol raised carotene levels anemia decreased filtration by kidneys causing medication toxicity HOARSE VOICE
what does severe hypothyroidism cause
myxedema ( loss of brain function, life threatening, dermatological changes, extreme hair loss)
