Thyroid (mine

Question 1

Exophthalmos

Answer 1

bulging of the eyes

most common cause Graves (hyper)

Question 2

TPOAB

Answer 2

thyroid peroxidase antibody

Question 3

what is the first and primary test done to check thyroid function

Answer 3

TSH

• esp if no history of thyroid illness but have symptoms
• if it is high or low, then consider checking thyroid panel

Question 4

what condition would you expect in a person with a HIGH thyroid stimulating hormone (TSH)

Answer 4

high TSH indicates that you have low thyroid hormones

TSH is from the pituitary

Question 5

what condition would you expect in a person with a HIGH thyroid stimulating hormone (TSH)

Answer 5

high TSH indicates that you have low thyroid hormones
TSH is from the pituitary

Conditions:
HYPOthyroidism (congenital=cretinism and primary)

secondary HYPERthyroidism

pituitary adenoma

hashimoto’s thyroditis (autoimmune)

amiodarone/ dopamine antagonist= drugs

ectopic TSH producing tumors

TSH producing pituitary adenoma

Question 6

what condition would you expect in a person with LOW TSH

Answer 6

primary HYPERthyroidism

secondary HYPOthyroidism
- TSH near zero!!

Tertiary HYPO thyroidism

graves disease (autoimmune)- has no effect on TSH levels

glucocorticoids= drugs

excessive exogenous thyroid hormone

high levels of chronic gonadotropin

Question 7

how much more active is T3 than T4

Answer 7

4-5 X more active

Question 8

what are the indications of performing a TSH test

Answer 8

screening for congential hypothyroidism

diagnose hypothyroidism, hyperthyroidism, pituitary or hypothalamic dysfunction

differentiate primary (thyroid) hypothyroidism from secondary (pituitary) and tertiary (hypothalamus) hypothyroidism

Question 9

what are the indications of performing a TSH test

Answer 9

screening for congential hypothyroidism

diagnose hypothyroidism, hyperthyroidism, pituitary or hypothalamic dysfunction

differentiate primary (thyroid) hypothyroidism from secondary (pituitary) and tertiary (hypothalamus) hypothyroidism

Question 10

what is TSH also called

Answer 10

thyrotropin

Question 11

what is the best test for screening of hypothyroid and hyperthyroid

!!!!

Answer 11

TSH

Question 12

what is the best test for screening of hypothyroid and hyperthyroid

!!!!

Answer 12

TSH

if normal= no other test needed

Question 13

what is it called when we treat hypothyroidism

Answer 13

levothyroxine treatment

aka the medication

Question 14

what is it called when we treat hypothyroidism

Answer 14

levothyroxine treatment

aka the medication

Question 15

what are the indications for Total T4 test

Answer 15

evaluates for hypo and hyper

newborn screening of congenital hypo

monitor therapy response for hypo or hyper

Question 16

what is the drawback to Total T4 test

Answer 16

con be influenced by elevations or declines in serum proteins giving false assumption of low or high levels

Question 17

what causes high total T4

Answer 17

excessive intake of iodine

hyperthyroidism (graves)

high doses of levothyroxine meds (for hypo Tx)

familial dysalbuminemic hyperthyroxinemia

hepatitis

Question 18

what decreases total T4

Answer 18

hypothyroid

pituitary, hypothalamic and iodine insufficiencies

protein def

• nephrotic syndrome
• reduced TBG and albumin = reduced protein bound to T4

Question 19

what are the indications for getting a free T4 test

Answer 19

evaluate signs of hypo or hyper

monitor Tx response of hypo or hyper

Question 20

what causes elevations in free T4

Answer 20

primary HYPERthyroidism (graves)

acute thyroiditis (hashimotos) - initial excess T4

fictitious hyperthyroidism

Question 21

what is fictitious hyperthyroidism

Answer 21

caused by treatment for hypo by too much levothyroxine

Question 22

what causes decreased T4 levels

Answer 22

primary hypothyroidism

pituitary/hypothalamic/iodine insuf

Question 23

Total T3

Answer 23

rarely checked

influenced by non thyroid diseases like liver problems

Question 24

why check Total T3

Answer 24

mainly to assist in diagnosis of hyper

suspected T3 toxicosis (rare)

administering drugs that interfere with conversion of T4 to T3 (amiodarone)

Question 25

what causes elevation in free T3

Answer 25

high altitude

HYPERTHYROIDISM

T3 toxicosis

Question 26

what causes decreased Free T3

Answer 26

HYPOTHYROIDISM

malnutrition (iodine def)

late pregnancy

Question 27

what test do we run if patient has no symptoms, but a decreased free T4 and is suspected of having a hereditary condition that would cause an increase in TBG

Answer 27

TBG test would be run

would also run to assess thyroid cancer

Question 28

when to order TgAB

Answer 28

in addition to TPOAb and TRAb for evaluating autoimmune thyroid disesase

or monitor cancer

Question 29

what are the two types of TRAb tests

Answer 29

TSI= thyroid stimulating immunoglbulin antibody

• measures net activity of TRAb
• good for graves and goiter

TBII- TSH receptor binding inhibiotr immunoglobulin

Question 30

when do you order TSI and TBII

Answer 30

for patients with extrathyroidal manifestations like exophtalmos but have a euthyroid

Question 31

what conditions do you see an increase in radioactive iodine uptake

Answer 31

graves
plummer disease (toxic multinodular goiter)
toxic adenoma (uninodular goiter)
thyroiditis (early hashimoto)

Question 32

what casues RAIU to decrease

Answer 32

hypo
thyroiditis late stages
iodine induced hyperthyroidism
drugs

Question 33

who to check thyroid labs on

Answer 33

newbors for congenital hypo
screening (TSH only) 
screen pt with hyperlipidemia
unknown cause of hyponatremia
consider hypertensive pt

Question 34

what does hypothyroidism cause in infants

Answer 34

irreversible damage to CNS
developmental defects
mental retardation

Tx is levothyroxine

Question 35

what to do if you get a low TSH

Answer 35

repeat TSH and check free T4 and T3 (thyroid panel)

if TSH normal, free T4/3 normal= lab error
if TSH low and free T4/3 high= hyperthyroid