Hypothyroidism

Question 1

describe the hormone pattern seen in primary hypothyroidism

Answer 1

high TSH

low T4

Question 2

describe the HPT axis

Answer 2

hypothalamus releases TRH (thyrotropin releasing hormone)

anterior pituitary releases TSH

thyroid releases T3 and T4

Question 3

give three autoimmune causes of hypothryoidism

Answer 3

hashimotos
spontaneous atrophic hypothryoidism
graves disease

Question 4

give three drugs that can cause hypothyroidisim

Answer 4

carbimazole
lithium
amiodarone

Question 5

worldwide what is the chief cause of hypothyroidism

Answer 5

iodine deficiency

Question 6

give four occasions where it may be necessary to change levothyroxine dosage

Answer 6

malabsorption
use of other drugs
pregnancy/oestrogen therapy
after surgical or iodine thyroid ablation

Question 7

what hormone pattern would you see in secondary hypothryoidism

Answer 7

low TSH

low T4

Question 8

what hormone pattern would you see in subclinical hypothyroidism

Answer 8

high TSH and T4 on the low end of normal

Question 9

how can you manage subclinical hypothyroidism

Answer 9

trial levothyroxine

Question 10

what are the classical features of hashimotos

Answer 10

• features of hypothyroidism
• goitre: firm and non-tender
• anti TPO antibodies and anti-Tg antibodies

Question 11

how can you manage hashimotos

Answer 11

normally use synthetic T4 +/- levothyroxine