hypothyroidism

Question 1

hyperthyroidism following administration of iodine or iodide

Answer 1

Jod-Basedow phenomenon

Question 2

reduction in thyroid hormone levels caused by ingestion of a large amount of iodine due to autoregulatory phenomenon that inhibits organification in the thyroid gland

Answer 2

Wolff–Chaikoff effect

Question 3

does T4 or T3 have a longer half life?

Answer 3

T4

Question 4

T4 has a half life of ____, T3 is ____

Answer 4

7 days; 1 day

Question 5

what is the primary binding protein of T3/T4?

Answer 5

thyroid binding globulin

Question 6

factors that incr TBG? (2)

Answer 6

1. estrogen (pregnancy, BCP)

2. congenital

Question 7

factors that decr TBG (2)

Answer 7

1. systemic illness

2. glucocorticoids

Question 8

best test of thyroid fxn

Answer 8

TSH

Question 9

thyroid dysfxn stemming from the thryroid

Answer 9

primary

Question 10

thyroid dysfxn stemming from the pit or the hypothalamus

Answer 10

secondary

Question 11

if you suspect secondary hypothyrodism, is the TSH reliable?

Answer 11

no, it will be constantly low

Question 12

what is the most common cause of hypothyroidism in iodine sufficient areas?

Answer 12

hashimotos thyroiditis

Question 13

how to tx hypothyroidism

Answer 13

levothyroxine (T4)

Question 14

when is tx of hypothyroidism indicated?

Answer 14

TSH >10

Question 15

when to recheck labs after starting levothyroxine?

Answer 15

1. 6 weeks later
2. switch meds
3. starts BCP
4. pregnant

Question 16

what happens to thyroid hormone during pregnancy?

Answer 16

needs for thyroid hormone increase

Question 17

mental status changes, hypothermia, hyperglycemia, respiratory failure, hypotension, bradycardia

Answer 17

myxedema coma

Question 18

what to measure for secondary hypothyroidism?

Answer 18

free T4