Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key

image

Play button

image

Play button

image

Progress

1/29

Click to flip

29 Cards in this Set

  • Front
  • Back
embryological origin of thyroid

(and congenital disorder)
between 2nd & 3rd pharyngeal pouches
migrates

thyroglossal cyst= remnant of thyroid at base of tongue

pyramidal lobe=remnant of thyroid duct
histology of thyroid
columnar epis
TSH causes to grow
only cells to uptake iodine
full of colloid
colloid
contents of thyroid epis
thyroglobulin & tyrosein
production of thyroid hormone
peroxidase
-oxidize iodine
-add iodine to tyroseine (MIT then DIT)
-couple 2 DIT to make T4

deiodinase
-activates T4 to T3 (mostly in blood)
-T3 enters nucleus
thyroid hormone in circulation
bound to thyroid binding globulin

(albumin 15%, transthrine 10%)
factors affecting TBG
(thyroid binding globin)

increased
-estrogen
-(congenital excess)

decreased
-hepatic dz
-(congenital defect)
function of Thyroid hormone
4 B's

bone growth (synergism w/GH)
brain maturation
beta adrenergic
-(increased CO, HR, SV & Ctx)
BMR increase
regulation of TH
TRH (in hypothal)
-stim'd by increased glyc use, GNG, lipolysis
-stims TSH in pit

inhibited by
-feedback inhibition by T3
-ant pit decreases sensitivity to TRH

TSI stimulates TSH
(Graves Dz)
thyroid abnormalities
TH excess
TH defic
Thyroid nodules/Ca
TH resistance
Nonthyroidal illness
autoimmune destruction of thyroid cells
Hashimoto's
causes of hypothyroid
hashimotos (#1 cause US)
iodine def (#1 cause world)
surgery
Pituitary
congenital
cretinism
big belly, infantile, decreased growth
cretinism
(congenital hypothyroid)
fatigue, dry skin, hair loss, weight gain, cold intolerance
hypothyroid
hypothermia, bradycardia, thickened dry skin
hypothyroid
hyporeflexia

(myxedema coma if severe)
hypothyroid (pathogmnemonic)
treatment for hypothyroid
replacement
-porcine
-synthetic (levothyroxine, liothyronine)
TH4 replacement
levothyroxine
7 day t 1/2
TH3 replacement
liothyronine
8 hr t 1/2
causes of goiters
TSH elevation (regardless of thyroid fctn)
-iodine deficiency
-Grave's (TSI stims R)
-primary hypothyroid
-thyroid adenoma (multinodular "goiter")
-secondary hyperthyroid (TSH secreting pituitary tumor)
causes of hyperthyroid
Grave's (most common)
Thyroiditis
Adenoma ("hot nodule", T3)
receptor cross reactivity (HCG, molar pregnancy, HCG, LH, FSH activate beta)
TSH secreting pituitary tumor
Iatrogenic/facticious
ectopic (struma ovari makes T4)
weight loss, increased appetite, BMR increased,

tachy, mental status, poor sleep

weak, fatigue, decreased ex tol
hyperthyroid
mechanism of Graves
autoimmune production of TSI (activates TSH R's)
pretibial edema
EOM hypertrophy
Grave's
(hyperthyroid)
thyroid storm
clinical dx (don't wait for labs)
tachy, diaphoretic (sweat)
tachy, diaphoretic, cardiac, neuro thermo instability
thyroid storm
underlying tyroid
-MVA
-accident
drugs that block TH synthesis
(peroxidases)

PTU
Methimazole
diffuse toxic goiter
Grave's
nodular toxic goiter
hyperthyroid (Plummer's-selective T3 secreting tumor)
diffuse simple goiter
iodine deficiency