Test 2 - RU thyroid Flashcards
what are the two thyroid hormones
thyroxine (T4)
triiodothyronine (T3)
the rate of extraction of ______ from the bloodstream and the rate at which T3 and T4 are synthesized are released from storage
regulated by _____
iodine
pituitary TSH
general term for enlargment of the thyroid
goiter
causes of a goiter
physiologic enlargemnt
iodoine def.
hashimoto thyroiditis
goitrogens - food or drugs that suppress synth of thyroid hormones
dyshormonogenesis - failure of hormone synth
goiter without thyroid hormone dysfunction
simple goiter
goiter associated with hyperthyroidism
toxic goiter
goiter occurring with high freq. in iodine def. geographic areas
endemic goiter
irregular enlargemnt of thyroid, resulting in nodule formation
nodular goiter
late stage of simle goiter in which goiter is most often nodular
nodular colloid goiter
decreased serum free T4
increased serum TSH
hypothyroidism
caused by iodine def.
seen in early childhood
cretinism
more common in women than men
primary idopathic
idoine def.
decreased cardiac output
decreased sympathetic activity
enlargment of tongue
accumulation of matrix in skin and viscera
myxedema
most common cause of hyperthyroidism
age 20-40 women
autoimmune with antibody to TSH receptor (results in increase TSH production and stimulation)
diffuse toxic goiter
exopthalmos (wide eyes)
grave’s disease
chronic autoimmune thyroiditis
inadequate production of thyroid hormones
women > men
slow, often inapparent course of enlarged and tender thyroid
massive formation of lymphoids with germinal centers
autoantibodies
hashimoto thyroiditis
viral infection - resulting in autoimmunity
enlarged thyroid
onset with neck pain
transient hyperthyroidism followed by hypothyroidism
subacute thyroiditis
“painless or silent thyroiditis”
upper respiratory viral infection
painful enlargement of thyroid gland with presence of giant cells
subacute granulomatous thyroiditis (DeQuervain’s disease)
benign tumor
adenomas
malignant tumor
carcinomas
most common thyroid cancer
often metastasizes to the cervical lymphnodes
psammoma bodies present (histologically)
papillary carcinoma
cancer originates from C cells of the thyroid
produces calcitonin - calcium lowering hormone
multiple endocrine neoplasia (MEN) syndrome IIa and IIb
medullary carcinoma