Thyroid

Question 1

The thyroid fx

Answer 1

produces thyroxine (T4) and triiodothyronine (T3)
these hormones act as as cellular energy release catalysts and influences the fx and health of every cell in the body

Question 2

Hypothyroid =

Answer 2

reduced cellular energy

Question 3

Hyperthyroid =

Answer 3

excessive cellular energy

Question 4

symptoms of hypothyroid

Answer 4

thick, dry skin
hyporeflexia
slow thoughts
weight gain of about 5-10 lbs
constipation
menorrhagia
easily chilled

Question 5

symptoms of hyperthyroid

Answer 5

smooth, silky skin
hyperreflexia
mind racing
weight loss of about 10 lbs
frequent stools
oligomenorrhea
heat intolerance

Question 6

Etiology of Hypothyroid

Answer 6

hashimoto thyroiditis
post-radioactive iodine
meds

Question 7

Meds causing hypothyroid

Answer 7

lithium
amiodarone
interferone

Question 8

hashimoto thyroiditis

Answer 8

autoimmune

Question 9

post-radioactive iodine treatment cause of hypothyroid

Answer 9

Graves disease tx

thyroid cancer tx

Question 10

Etiology of hyperthyroid

Answer 10

graves disease
toxic adenoma
thyroiditis
meds

Question 11

Toxic adenoma causing hyperthyroid

Answer 11

metabolically active lesion

Question 12

thyroiditis causing hyperthyroid

Answer 12

viral
autoimmune
postpartum
transient

Question 13

Meds causing hyperthyroid

Answer 13

Amiodarone

interferon

Question 14

Test for thyroid

Answer 14

TSH
Free T4
Total T4
Free T3
Total T3
Antiperoxidase

Question 15

TSH lab

Answer 15

evaluates hypothalmic pituitary thyroid axis function
TSH receptors are found in follicular cells
most common way to determine hypo/hyper thyroid
N: 0.4-4.0

Question 16

free thyroxine (FT4) lab

Answer 16

this is the unbound, metabolically active potion of thyroxine
N: 10-27

Question 17

total thyroxine ( Total T4) lab

Answer 17

rarely indicated
total protein bound and free thyroxine
altered in the absence of thyroid disease from pregnancy, hepatitis, estrogen, methadone
N: 4.5-12.0

Question 18

Free T3 lab

Answer 18

rarely indicated test
unbound metabolically active portion of triidothyronine
4x more active than FT4
only 20% is from the thyroid, the rest from conversion of T4 to T3
N: 3.5- 7.7

Question 19

Antiperoxidase antibody lab

Answer 19

a test to help detect autoimmune thyroid disease
measures an antibody against peroxidase
N: depends on lab

Question 20

If low thyroxine (FT4) and high TSH

Answer 20

hypothyroid

Question 21

Treating hypothyroid with levothyroxine

Answer 21

1.6mcg/kg in adults
1.0mcg/kg in elderly
4.0mcg/kg in children
> 50% in pregnancy (start with initial 33% increase)
Check TSH 8 weeks after therapy started
take with water on empty stomach
2 hours between calcium, iron, aluminum, magnesium

Question 22

If high thyroxine (FT4) and low TSH

Answer 22

hyperthyroid or hypothyroid that is over treated

Question 23

Hyperthyroid Tx

Answer 23

start beta blocker for tachy
PTU or methimazole
radioactive iodine with end results of thyroid ablation or hypothyroid

Question 24

If elevated TSH and normal FT4

Answer 24

subclinical hypothyroid
would recommend tx for TSH > 5 if pt has goiter or pos antibodies
tx if trying to achieve pregnancy

Question 25

After 8 weeks of levothyroxine therapy

Answer 25

repeat TSH if > 4 increase dose by 12.5-25 If < 0.5 decrease dose by 12.5-25 if 0.5-2.0 keep dose same and rpt in 6 months

Question 26

thyroid nodule =

Answer 26

palpable mass not a dx low risk of malignancy

Question 27

Suspect malignancy of nodule if

Answer 27

``` hx of head or neck irradiation pain dysphonia hemoptysis regional lymphadenopathy hard, fixed mass ```

Question 28

If there is a thyroid nodule

Answer 28

Draw TSH If suppressed do a scan if "hot" nodule do ablation (not cancer). If not "hot" do fine-needle aspiration biopsy If TSH not suppressed then fine needle aspiration