Thyroid Function Tests

Question 1

What can be used alone as a screening test for Thyroid disease?

Answer 1

TSH

If it is abnormal then do T3/T4

Question 2

What happens to TSH in hyperthyroidism?

Answer 2

TSH suppressed by high thyroid hormones

-Low TSH levels

Question 3

What happens to TSH in hypothyroidism?

Answer 3

TSH is high as trying to stimulate more thyroid hormone release

• Exception is pituitary or hypothalamic cause of secondary hypothyroidism
• Here the TSH levels would be low

Question 4

What happens to T3/4 in hyperthyroidism?

Answer 4

Expect raised T3/4

Question 5

What happens to T3/4 in hypothyroidism?

Answer 5

Low T3/T4

Question 6

TSH levels in hypothyroidism?

Answer 6

Raised TSH

Question 7

TSH levels in hyperthyroidism?

Answer 7

Suppressed TSH

Question 8

Hyperthyroidism levels of TSH and T3/4?

Answer 8

T3/T4= High 
TSH = Low

Question 9

Primary hypothyroidism levels of T3/T4 and TSH?

Answer 9

T3/T4 = Low 
TSH = High

Question 10

Secondary hypothyroidism levels of T3/T4 and TSH?

Answer 10

T3/T4 = Low 
TSH = Low

Question 11

What are autoantibodies present in Grave’s disease and Hashimoto’s?

Answer 11

Antithyroid peroxidase (Anti-TPO) ABs

Question 12

Autoantibodies present in Grave’s disease, Hashimoto’s and thyroid cancer?

Answer 12

Antithyroglobulin Antibodies

Question 13

Cause of Grave’s disease?

Answer 13

TSH Receptor AB’s

Question 14

What does a radioisotope scan diagnose?

Answer 14

Investigate hyperthyroidism & thyroid cancers

-Show thyroid gland function