34 - Thyroid Disorders

Question 1

more common in what gender

Answer 1

women

Question 2

Hypothyroidism is an ______ TSH level

Answer 2

elevated

Question 3

What is subclinical hypothyroidism?

Answer 3

defined by an elevated TSH with normal thyroid hormone levels

Question 4

Symptoms of hypothyroidism

Answer 4

fatigue, impaired memory, bradycardia, dry skin and hair, constipation, cold intolerance

Question 5

What does dessicated thyroid contain?

Answer 5

both t4 and t3

Question 6

Hypothyroidism:

What is the treatment of choice?

Answer 6

Levothyroxine (L-T4) to normalize TSH level

Question 7

Hypothyroidism:

Dose adjust for levothyroxine every ____ weeks as needed

Answer 7

4-6

Question 8

Hypothyroidism:

Dose of levothyroxine in adults

Answer 8

1.6 mcg/kg/day

Question 9

Hypothyroidism:

Dose of levothyroxine in newborns

Answer 9

10-16 mcg/kg/day

Question 10

Hypothyroidism:

When do you give liothyronine (T3) ?

Answer 10

short term management of patients with thyroid cancer undergoing withdrawal of L-T4 when recombinant TSH is not an option or in order to prepare for radioactive iodine therapy

Question 11

Hypothyroidism in Pregnancy:

How do you manage women who are already taking thyroid hormone replacement therapy?

Answer 11

• increase the dose by 2 extra tabs/week immediately after a positive pregnancy test
• further dose adjustments based on TSH levels

Question 12

Hypothyroidism in Pregnancy:

When do you get TSH levels drawn?

Answer 12

-have TSH levels q 6 weeks or 4 weeks after dose adjustment

Question 13

Hypothyroidism in Pregnancy:

For those not on therapy, what is the target TSH?

Answer 13

TSH should be maintained at < 4 mU/L

Question 14

Hypothyroidism in Pregnancy:

When would you initiate therapy if they’re not on it already?

Answer 14

if the TSH > 10 mU/L or if the patient has TSH > 4 mU/L and is positive for anti-TPO antibodies then you want to initiate thyroid replacement therapy

Question 15

Hypothyroidism:

How do you explain the safety of thyroid replacement in pregnancy and breastfeeding?

Answer 15

thyroid replacement is completely safe in pregnancy and breastfeeding and is important to ensure a healthy pregnancy and normal fetal development

Question 16

Hypothyroidism in Breastfeeding:

How do you treat it?

Answer 16

same as non-breastfeeding women

Question 17

Thyrotoxicosis is also caused ______

Answer 17

hyperthyroidism

Question 18

Hyperthyroidism is when TSH is ____

Answer 18

low

Question 19

Define subclinical hyperthyroidism

Answer 19

TSH is low but thyroid hormone levels are normal

Question 20

Symptoms of hyperthyroidism

Answer 20

weight loss, palpitations, diarrhea, heat intolerance, anxiety

Question 21

What drugs can suppress TSH

Answer 21

corticosteroids, domperidone, metoclopramide, dopamine

Question 22

Hyperthyroidism:

What can radioactive iodine cause as a side effect?

Answer 22

hypothyroidism

Question 23

Hyperthyroidism:

Radioactive iodine is CI in ____

Answer 23

pregnancy

Question 24

Hyperthyroidism:

What are the 2 antithyroid drugs?

Answer 24

• methimazole

- PTU

Question 25

Hyperthyroidism: | How do antithyroid drugs work?

Answer 25

decrease production of thyroid hormone

Question 26

Hyperthyroidism: | What can PTU also do?

Answer 26

block conversion of L-T4 to T3

Question 27

Hyperthyroidism: | When do antithyroid drugs need to be stopped?

Answer 27

Need to be stopped 5 days prior to a thyroid scan or treatment with iodine

Question 28

Hyperthyroidism: | Which antithyroid drugs is preferred? Why?

Answer 28

MTZ is preferred due to lower incidence of hepatotoxicity

Question 29

Hyperthyroidism: | In what situation is PTU preferred over MTZ?

Answer 29

1st trimester of pregnancy

Question 30

Hyperthyroidism: | How do beta blockers work?

Answer 30

ameliorate the symptoms of adrenergic excess and are usually used adjunctively in the management of Graves disease or toxic nodules

Question 31

Hyperthyroidism: | Which beta blockers can decrease conversion of L-T4 to T3

Answer 31

propranolol and nadolol

Question 32

Hyperthyroidism: | How does iodine (Lugol solution) work?

Answer 32

blocks thyroid hormone production

Question 33

Hyperthyroidism: | When should iodine (Lugol solution) be given in relation to antithyroid drugs?

Answer 33

1 hour after administration of an antithyroid drug

Question 34

Hyperthyroidism: | What can methimazole and PTU cause?

Answer 34

neutropenia

Question 35

Hyperthyroidism: | How can corticosteroids help?

Answer 35

they lower the level of free T3

Question 36

Hyperthyroidism: | Place of selenium in therapy?

Answer 36

Selenium 100mcg BId may prevent worsening of mild Graves orbitopathy and can be considered as supplemental therapy

Question 37

How do you treat thyroid storm?

Answer 37

- antithyroid meds, BB and corticosteroids - use acetaminophen for hyperthermia - plasmapheresis can be considered in unresponsive cases

Question 38

Hyperthyroidism and Pregnancy: | Wait how long after radioactive iodine before conceiving ?

Answer 38

6 months

Question 39

Hyperthyroidism and Pregnancy: | ____ is preferred antithyroid for 1st trimester of pregnancy

Answer 39

PTU

Question 40

Hyperthyroidism and Pregnancy: | Can you give MTZ?

Answer 40

if PTU is CI

Question 41

Hyperthyroidism and Pregnancy: | What is the treatment for 2nd and 3rd trimester?

Answer 41

MTZ

Question 42

Hyperthyroidism and Pregnancy: | What are some other options?

Answer 42

BBs or iodine in 1st trimester with careful monitoring

Question 43

Hyperthyroidism and Pregnancy: | What do you monitor and how often?

Answer 43

TSH, fT3, fT4 q6-8 weeks

Question 44

Hyperthyroidism and Pregnancy: | What do you need to measure at 22 weeks gestation

Answer 44

TRAb titre should be measured -if positive, repeat at 30-34 weeks

Question 45

Hyperthyroidism and Pregnancy: | A high titre of TRAb means what?

Answer 45

increased risk of hyperthyroidism for the baby

Question 46

When on antithyroid drugs, when will neutropenia be seen if it happens?

Answer 46

1st 90 days

Question 47

When on antithyroid drugs, when will hepatic effects be seen if it happens?

Answer 47

1st 120 days

Question 48

Hyperthyroidism and Breastfeeding: | What antithyroid drug is preferred?

Answer 48

- MTZ preferred but can use PTU | - can use BBs