Hormone Measurement

Question 1

What’s the first hormone we measure with abnormal thyroid function

Answer 1

TSH

Question 2

What’s the usual compensatory for low thyroxin?

Answer 2

TSH spike

Question 3

Is an abnormal endocrine test absolutely definitive?

Answer 3

No, the reference range includes 95% of population. Even if the number falls out the range, it doesn’t mean there is a problem

Question 4

What does a dynamic endocrine test involve?

Answer 4

sampling at multiple time points and may involve stimulation or suppression of the gland to see if there is appropriate response

Question 5

Why are dynamic tests used less these days?

Answer 5

they are replaced by better assays

Question 6

What’s the use of dexamethasone suppression test?

Answer 6

use to assess adrenal gland and pituitary (Cushing’s especially)

Question 7

How does a dexamethasone suppression test work?

Answer 7

Dexamethasone is a very potent steroid, and it should cause a reduction in ACTH release due to negative feedback

Question 8

What’s the use of synacthen stimulation test?

Answer 8

assess adrenal under-activity. Synacthen is a synthetic ACTH

Question 9

In a GH stimulation test, what are the stimuli?

Answer 9

exercise, hypoglycaemia, arginine

Question 10

What’s the principle of competitive immunoassay?

Answer 10

antibody binding competition between labelled hormone and natural hormone is blood. The higher the label signal, the lower the hormone concentration

Question 11

What’s the principle of sandwich immunoassay

Answer 11

sandwich natural hormone between two antibodies, one labelled. The higher the signal, the higher the hormone concentration