Thyroid Studies Flashcards Preview

Medicine > Thyroid Studies > Flashcards

Flashcards in Thyroid Studies Deck (20):
1

TSH

responsible for the synthesis and secretion of T3 (triiotathyronine) /T4 (thyroxine) -best screening test for thyroid function

2

T3 and T4 function

assist with cellular respiration and metabolism

3

TRH

thyrotropine releasing hormone (comes from hypothalamus)

4

Thyroid feedback systems are present in the

hypothalamus and anterior pituitary

5

TSH screening test normal value

normal 0.5-5.5 mlU/L -taken in red or marble top -not useful if they have had surgery on or damage to the anterior pituitary

6

interfering factors in the TSH screening

radioisotope administration severe illness drugs

7

increased TSH because of drugs could be

lithium

potassium iodide

TSH injection

8

decreased TSH because of drugs could be

ASA

NSAIDS

heparin

corticosteroids (Prednesone in the case of RA)

9

Thyroxine (T4)

More abundant thyroid hormone

10

Triiodothryonine (T3)

thyroid hormone that is secreted in lesser amounts, but that is more metabolically active

-is T4 less one iodine

11

Thyroid binding globulin (TBG)

protein that binds to T3/T4

-free T4 and T3 is what actually does the work

-produced in the liver

-free hormone levels are not altered by changes in TBG (stays constant)

-changes in TBG may affect total thyroid hormone levels

12

free T4 test

2nd test that you would order in a thyroid work-up

13

increase in TBG might be because of

high estrogen states (OCP, pregnancy, hormone replacement therapy)-gives total T4 elevation

infectious hepatitis (causes inflammation and churns out extra hormone)

genetic TBG excess

14

decrease in TBG might be because of

liver disease (cirrhosis)

malnutrition

protein losing nephropathy

androgens

estrogen deficiency

major stress

15

thyroid screening tests

1. TSH

2. Free T4

***Need to pay attention to whether it says FREE otherwise assume it is total

16

thyroglobulin work up

indicated for someone who has a thyroid tumor

used as a tumor marker

-protein that is made by the thyroid gland

-elevated levels indicate residual thyroid tissue

17

increased TSH level indicates

hypothyroidism 

-thyroid is not responding to the TSH and pituitary is compensating by making more 

>5.5 mgU/dl

18

decreased TSH level indicates

hyperthyroidism

-pituitary is reading that thyroid hormone levels are high and decreases secretion of TSH

-<0.5 mgU/dl

19

Two tests that are used to diagnose autoimmune disease

1. thyroid stimulating immunoglobulin (Graves dx)

2. thyroid antibodies (Hashimotos)

-anti-TPO antibodies-most sensitive

-antithyroglobulin antibodies-less sensitive

20

Decks in Medicine Class (146):