thyroid (SOME)

Question 1

sx of hypothyroidism

Answer 1

hypoactivity: fatigue, depression, cognitive impairment,
cold intolerance
wt gain
dry skin, coarse hair, dry brittle nails
lateral eyebrow thinning
constipation, menorrhagia,
exertional dyspnea,
delayed DTR

Question 2

sx of hyperthyroidism

Question 3

medications that can cause hypothyroidism

Answer 3

lithium
amiodarone
methimazole
PTU
interferon
rifampin

Question 4

how can amiodarone cause hypothyroidism?

Answer 4

via antithyroid action of iodine- blocking T4,3 secretion, stop TH from entering peripheral tissue

Question 5

intentional etiologies of hypothyroidism

Answer 5

surgery
ablative (I-131)
radiation therapy

Question 6

how does lithium cause hypothyroidism

Answer 6

impairs T4,T3 release

Question 7

how does interferon cause hypothyroidism

Answer 7

causes sx that look like hashimotos and goes away after med is stopped

Question 8

how does rifampin cause hypothyroidism

Answer 8

it increases levothyroxine metabolism- concern for compromised fx at baseline

Question 9

which conditions would have low iodine uptake on radioactive uptake scan?

Answer 9

thyroiditis
drug induced (iodine, amiodarone, TH)

Question 10

how can amiodarone cause hyperthyroidism? (two types)

Answer 10

type 1: excess hormone synthesis
type 2: damage thyroid cells causing T3,T4 release

Question 11

how does iodine excess cause hyperthyroidism

Answer 11

via Jod-Basedow phenomenon

Question 12

Free T4 levels in T3 thyrotoxicosis

Answer 12

normal or low

Question 13

thyrotoxicosis vs hyperthyroidism

Answer 13

they are used interchangeably BUT
thyrotoxicosis is when theres too much thyroid hormone in body in general while hyperthyroidism is excess from the thyroid gland

Question 14

how estrogen affects “total” labs

Answer 14

increases total T4 and T3 bc of increased TBG
even tho thyroid function is actually ok

Question 15

how illness affects “total” labs

Answer 15

decrease total T3 and T3 d/t decreased protein levels
even tho thyroid function is actually ok

Question 16

4 types of thyroid cancer

Answer 16

papillary thyroid cancer
follicular carcinoma
medullary carcinoma
anaplastic carcinoma

Question 17

what is the most common type of thyroid cancer?

Answer 17

papillary thyroid cancer

Question 18

which thyroid cancer has the best prognosis?

Answer 18

papillary thyroid cancer

Question 19

which thyroid cancer has the worst prognosis?

Answer 19

anaplastic carcinoma– 100% mortality!!

Question 20

which two thyroid cancers are treated with thyroidectomy, RAI w/ I-131 and TSH suppression?

Answer 20

papillary thyroid cancer
follicular carcinoma

Question 21

how does papillary thyroid cancer metastasize?

Answer 21

lymphatics

Question 22

how do you monitor papillary thyroid cancer

Answer 22

neck US
thyroglobulin levels
I-131 metastatic surveys
PET scans

Question 23

what does the prognosis of follicular carcinoma depend on?

Answer 23

extent of extrathyroidal extension and vascular invasion
in general it has a good prognosis

Question 24

how does follicular carcinoma metastasize?

Answer 24

hematogenously

Question 25

which variant of follicular carcinoma may be more aggressive?

Answer 25

hurthle cell variant

Question 26

what are the two types of medullary carcinoma?

Answer 26

sporadic and familial

Question 27

which type of medullary carcinoma is more common?

Answer 27

sporadic

Question 28

which of the medullary carcinomas has C cell hyperplasia?

Answer 28

familial medullary carcinoma

Question 29

what procedure improves prognosis for familial medullary carcinoma?

Answer 29

prophylactic thyroidectomy

Question 30

what genetic screening can be done for both types of medullary carcinoma?

Answer 30

germ line mutation of RET oncogene

Question 31

how does medullary carcinoma metastasize?

Answer 31

early before tumor is palpable

Question 32

why dont we use R-131 to treat medullary carcinomas?

Answer 32

bc the rumors are not iodine avid

Question 33

tx for medullary carcinomas

Answer 33

thyroidectomy neck dissection

Question 34

what is the serum marker for medullary carcinoma? how can you diagnose it?

Answer 34

calcitonin diagnosed with FNA

Question 35

which type of thyroid cancer is rare and more common in elderly?

Answer 35

anaplastic carcinoma

Question 36

tx for anaplastic carcinoma

Answer 36

palliative care

Question 37

how does anaplastic carcinoma tend to present

Answer 37

rapidly expanding, fixed, hard thyroid mass

Question 38

which cancer can be seen as a late de-differentiation of papillary thyroid carcinoma?

Answer 38

anaplastic carcinoma

Question 39

what supplement should be held before getting TSH levels? for how long?

Answer 39

Biotin for 2-3 days

Question 40

abbreviation for TSH receptor antibodies

Answer 40

Anti-TSHR TRab

Question 41

abbreviation for thyroid peroxidase antibody

Answer 41

TPO Ab

Question 42

what is the gold standard for evaluating thyroid nodules?

Answer 42

fine needle aspiration (FNA)

Question 43

which type of nodule should you never stick a needle in?

Answer 43

hot nodules

Question 44

which type of nodule should undergo FNA biopsy? why?

Answer 44

cold nodules they are more likely to be cancerous

Question 45

what is a hot nodule?

Answer 45

hyperfunctioning nodules that take up more of the isotope compared to normal thyroid tissue

Question 46

which type of nodule is more likely to be cancerous?

Answer 46

cold nodules

Question 47

what are cold nodules?

Answer 47

non-functioning nodule they take up less isotope

Question 48

in general, thyroid US are useful for..

Answer 48

finding out the size and texture of the gland and nodules

Question 49

how big must a nodule be to biopsy it?

Answer 49

1cm

Question 50

which screening procedure cannot differentiate follicular adenoma from follicular carcinoma?

Answer 50

fine needle aspiration

Question 51

what is the initial diagnostic study in euthyroid nodular disease?

Answer 51

fine needle aspiration

Question 52

when can you get a thyroid scan Tc99?

Answer 52

if TSH is low or FNA shows evidence of follicular neoplasia

Question 53

what is a warm nodule?

Answer 53

functioning with similar risk of malignancy as cold nodule

Question 54

what can cause a falsely low uptake with I-131?

Answer 54

iodine exposure

Question 55

if theres a nodule, you check TSH and its high or low, whats the next step in evaluation?

Answer 55

I-131 uptake and scan