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Flashcards in Thyroid Deck (28):
1

therapuetic effect Radioactive idoine

 

contraindicated

hyperfunction thyroid takes up and is ablated

most patients will develop lifelong hypothyroidism and require lifetime thyroid hormone

 

contraindicated in severes Grave's orbitopathy, especially in smokers with eye involvement and in pregnancy 

2

secondary hypothyroidism = 

 

tertiary = 

inadequate secretion or production of TSH from pituitary

 

inadequate secretion or production of TRH from hypothalamus

3

not always found in Grave's patients, but a very specific finding

TSI thyroid stimualting imunnoglobulins

3

for secondary hyperthyroidism

TSH

T4

TSI

Thyroid uptake

Thyroid Scan

Treatment

TSH high or high normal

T4 high

TSI negative

Thyroid uptake NA

Thyroid Scan NA

Treatment pituitary surgery (pituitary adenoma)

4

TSH, T3/T4 levels in  Graves

TSH low

high normal

4

mechanism+indication methmazole

 

side effects

hyperthyroidism

inhbits synthesis of thyroid hormes by blocking oxidation of iodine in the thyroid gland

 

reversible agranulocytosis

rash, joint pain, headache

5

driving force for thyrotoxicosis

thyroid stimualting immunoglobulin TSI

6

first step in differentiating between causes of primary hyperthyroidism

 

findings

radioiodine uptake/scan

Graves = high uptake, diffuse, bilateral

Hashimotos, granulomatous thyroiitis = low uptake

Toxic nodule or multinodular goiter = focused intense uptake

8

pathogenesis of lymphocytic (Hashimotos) thyroiditis

sensitization of lymphocytes to thryoglobulin, thyroid peroxidase, TASH receptor

cytokine release and inflammation ulitimately result in glandular destruction 

9

in secondary/tertiary hypopthyroidism 

TSH

Free T4, T3

thryroid peroxidase, thyroglobulin antibodies

TSH low or low normal

Free T4, T3 low

thryroid peroxidase, thyroglobulin antibodies negative

10

mxedema coma

severe hypothyroidism

multiorgan dysfunction

hypoventilation

hypotension

CNS changes

12

for toxic multinodal goiter or solitary toxic nodule

TSH

T4

TSI

Thyroid uptake

Thyroid Scan

Treatment

TSH low

T4 high

TSI negative

Thyroid uptake high

Thyroid Scan nodular, focal

Treatment - Methimazole, PTU, radioactive iodide, resection

13

Common symptoms hyperthyroidism

emotional lability
palpitations
weakness/fatigability
voracious apetit with weight loss
hyperkinesia, rapid speach
fine tremor
most skin
lid lag, state, proptosis
tachycardia, accentuated first heart sound, A-fib
heat intolerance

14

halflife Levothyroxine (T4)

 

liothyronine (T3)

Levothyroxine T4 - 6-7 days

LiothyronineT3 -

15

mechanism and indication propylthiouracil

adjunct for hyperthyroidism - refractory to methimazole or pregnant

 

inhibits synthesis of thyroid hormone by blocking oxiation of iodine, also partioanll inhibits periphera deiodination of T4 to T3

 

reversible agranulocytosis, hepatic failure

16

secondary thyroidititis due to

TSH secreting pituitary adenoma

17

Treatment for Hashimotos

Thyroid hormone (most often T4, levothyroxine)

 

(T3 liothyronine is also used, but has short half-life and requires rapid dosig)

18

pathophys for orbitopathy in Graves

sentization of T lymphocytes or T killer cells to TSH-R antigen found in thyroid follicular cells and orbital fibroblasts

19

most common causes of primary hyper thyroidism 

Graves

toxic multinodal goiter

solitary toxic (follicular) adenoma

thyroitis - inflammation

19

therapeutic effects of iodie

inhibits hormone release

decreasses vascularity, size,, fragility of hyperplastic glands (pre-op utility)

20

first test for suspected thyroid disease,

 

if this is abnormal, high suspicion of ____ and follow-up test=

TSH 

 

if abnormal, high suspicion for central process,

followed with free T4 testing

21

for thyroiditis

TSH

T4

TSI

Thyroid uptake

Thyroid Scan

Treatment

TSH low

T4 high

TSI negative

Thyroid uptake low

Thyroid ScanNA

Treatment - beta blockers, supportive care

23

other Rx for hyperthyroidism

Beta blocker  (block adrenergic effects of thyroid hromone)

Lugols solution - oral iodine, Jod-basedow effect (hyperthyroidism following iodine admin)

Chlesturamine - binds thyroid hormone in gut during enterohepatic circulation

24

in Euthyroid...

TSH

Free T4, T3

thryroid peroxidase, thyroglobulin antibodies

TSH - normal

Free T4, T3 normal 

thryroid peroxidase, thyroglobulin antibodies negative

25

in primary hypothyroidism

TSH

Free T4, T3

thryroid peroxidase, thyroglobulin antibodies

TSH elevated

Free T4, T3 low

thryroid peroxidase, thyroglobulin antibodies positive

26

for graves

TSH

T4

TSI

Thyroid uptake

Thyroid Scan

Treatment

TSH low

T4 high

TSI positive

Thyroid uptake high

Thyroid Scan diffuse, homogenous

Treatment - methimazole, PTU, radioactive iodine, resection

27

primary treatment options for Graves and other high uptake modalitiies of hyperthyroidism (toxic nodules)

Methimazole - inhibitor of thyroidal iodine organification,
(generally preferred, longer dosing)

propylthiouracil - inhibitor of thyroidal iodine organification, 
(preferred in pregnancy, though hepatotoxicity possible)

Radioactive iodine

28

most common casue of primary hypothyroidsm

lymphocytic thyroditis (Hashimotos)