Thyroid Studies Flashcards Preview

Medicine > Thyroid Studies > Flashcards

Flashcards in Thyroid Studies Deck (20)
Loading flashcards...
1
Q

TSH

A

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

2
Q

T3 and T4 function

A

assist with cellular respiration and metabolism

3
Q

TRH

A

thyrotropine releasing hormone (comes from hypothalamus)

4
Q

Thyroid feedback systems are present in the

A

hypothalamus and anterior pituitary

5
Q

TSH screening test normal value

A

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
Q

interfering factors in the TSH screening

A

radioisotope administration severe illness drugs

7
Q

increased TSH because of drugs could be

A

lithium

potassium iodide

TSH injection

8
Q

decreased TSH because of drugs could be

A

ASA

NSAIDS

heparin

corticosteroids (Prednesone in the case of RA)

9
Q

Thyroxine (T4)

A

More abundant thyroid hormone

10
Q

Triiodothryonine (T3)

A

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

-is T4 less one iodine

11
Q

Thyroid binding globulin (TBG)

A

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
Q

free T4 test

A

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

13
Q

increase in TBG might be because of

A

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
Q

decrease in TBG might be because of

A

liver disease (cirrhosis)

malnutrition

protein losing nephropathy

androgens

estrogen deficiency

major stress

15
Q

thyroid screening tests

A
  1. TSH
  2. Free T4

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

16
Q

thyroglobulin work up

A

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
Q

increased TSH level indicates

A

hypothyroidism

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

>5.5 mgU/dl

18
Q

decreased TSH level indicates

A

hyperthyroidism

  • pituitary is reading that thyroid hormone levels are high and decreases secretion of TSH
  • <0.5 mgU/dl
19
Q

Two tests that are used to diagnose autoimmune disease

A
  1. thyroid stimulating immunoglobulin (Graves dx)
  2. thyroid antibodies (Hashimotos)
    - anti-TPO antibodies-most sensitive
    - antithyroglobulin antibodies-less sensitive
20
Q
A

Decks in Medicine Class (146):