thyroid Flashcards
thyroid functions
2” butterfly shaped gland in neck
secretes triiodothyronine (T3) and thyroxine (T4)
regulates body metabolism, which influences almost every body system
what is a necessary component in the synthesis of thyroid hormone?
iodine
thyroid dysfunctions
hyper or hypo
*primary disorders most common
*more likely in women
*thyroid enlargement (goiter) can occur with both
goiter
enlargement of thyroid gland with or without symptoms of thyroid dysfunction
*excess pituitary TSH
*low iodine levels
*enlargment can occur from goitrogens (food/substances that promote enlargemnet)
hypothyroidism
insufficient levels of the thyroid hormones T3 and T4
(primary + secondary)
primary hypothyroidism
increase in release of TSH from pituitary
release of TSH indicates a …
hypoactive thyroid
what is the most common cause of hypothyroidism?
hasimoto’s thyroiditis, autoimmune disorder
(decrease T3 and T4, increase TSH)
Hashimoto’s thyroiditis
hypothyroidism
thyroid receptor antibodies
antithyroglobulin antibody
antithyroperoxidase antibody (hallmark of disorder)
risk factors for hypothyroidism
female
>50
white
pregnant
hx of autoimmune disorders
fam hx
meds (lithium, amiodarone)
HYPERthyroidism treatments
EARLY s/s of hypothyroidism
intolerant to cold
weight gain
lethargy, fatigue
memory deficit
poor attention span
increased cholesterol
muscle cramps
increased carotene levels
constipation
decreased fertility
puffy face
hair loss
brittle nails
LATE s/s of hypothyroidism
below normal temp
bradycardia
weight gain
decreased LOC
thick skin
cardiac complications [cardiomegaly (enlarged heart)]
how does hypothyroidism affect the body?
raises cholesterol; HLD
raises carotene; yellows skin
causes anemia
decreased kidney filtration (risk medication toxicity)
hoarse voice
myxedema
severe hypothyroidism (COMA)
dermatological change –> thick skin and nails, extreme hair loss, puffy face
diagnosing hypothyroidism
high TSH level
low T3 and T4
antithyroglobulin (anti-Tg)
antithyroperoxidase (anti-TPO) ATBs
diagnosing primary hypothyroidism
high TSH
low T4
diagnosing secondary hypothyroidism
normal TSH
low T4
treatment for hypothyroidism
levothyroxine
*replacement hormone therapy (T4)
MOA: converted to T3 in body
half life= 7 days
surgery, if necessary
*watch for bleeding/warfarin
hyperthyroidism
aka thyrotoxicosis
excessive secretion of T3 and T4
*primary: thyroid
*secondary: pituitary
*tertiary: hypothalamus
most common cause of hyperthyroidism
grave’s disease
autoimmune stimulation of thyroid gland
causes of hyperthyroidism
thyroid adenoma
subacute thyroiditis
toxic multinodular goiter
excessive iodine ingestion (jod-besedow syndrome)
excessive thyroid hormone replacement
risk factors of hyperthyroidism
female
>40
white
pregnant
fam hx of graves
meds (amirodarone)
excess iodine intake
grave’s disease
hyperthyroidism
autoimmune disorder
excess T3 and T4
thyroid stimulation ATBs
s/s of graves disease
nervous
insomnia
sensitive to heat
weight loss
enlarged/palpable gland
bruit (d/t high blood flow in gland)
atrial fibrillation
myxedema
exophthalmos
