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Flashcards in Thrombophilia Deck (27):
1

Thrombophilia

= hypercoag state

2

A decrease in what proteins are assc with an inherited thrombophilia?

antithrombin 3
protein C
protein S

3

An increase in what proteins/mutations are assc with an inherited thrombophilia?

Factor V Leiden
prothrombin gene mut G20210
Factor 7, 8, 9, 11
vWF
MTHFR gene

4

Why are Factor V Leiden pts hyper coagulable?

They are resistant to Protein C (makes them immortal)
*other than this, they clot normally

5

What can you expect the clinical history to be of a pt with an inherited hypercoag state?

thrombosis at early age
Family history of thrombosis
thrombosis at unusual site

6

T or F: one defect is enough to cause a person to form frequent thrombi

F: the body has redundancy/ability to compensate. It will take multiple deficiencies or risk factors

7

Why do oral contraceptives lead to a hypercoag state?

increases levels of estrogen inc risk for thrombosis by decreasing antithrombin 3 and increasing B-thromboglobulin

8

What are clinical presentations of antiphospholipid syndrome?

* fetal loss in 2nd trimester
thrombosis
long PTT

9

WHat is the pathogenesis of antiphospholipid syndrome?

Ab against membrane
-anti-cardiolipin, phosphatidyl serine, phosphatidic acid
-Beta 2 GPI and prothrombin have some role too

10

T or F: A person with antiphospholipid Ab syndrome will have a normal correction PTT

F: they have an Ab that will prolong the PTT even in the presence of normal plasma

11

What test will prove the presence of a lupus anti-coagulant?

correctional with hexagonal phase phospholipid

dilute russel viper venom test

**they will correct/have normal PTTs with these?

12

What part of the clotting cascade is the lupus anti-coag Ab syndrom/lupus anti-coag?

X--> Xa +V +prothrombin--> thrombin

13

What do you need in order to Dx antiphospholipid syndrome?

at least 1 clotting assay test
at least 1 Ab present

14

What effect does dipyridamole have on a platelet?

inhibits them by inhib phospho-diesterase

*stops the breakdown of cAMP to AMP = Inc cAMP = inhibits platelets

15

What effect does abciximab have on a platelet?

Ab to GpIIb/IIIa to inhibit platelet activation

16

Stasis causes _____

thrombosis

17

What is the difference between a white and red thrombi?

white: arterial, high blood flow

red: venous, stasis

18

What acts near the endothelium to inhibit thrombosis?

-antithrombin 3 inactivates thrombin, Xa, 9a
-thromodulin binds thrombin
-heparin-like molecule
-PGI2 and NO secretion

19

Describe the effect that HIT has on the platelet count

drop 5-7 days after heparin admin
*drop in 24 hrs if previous heparin historm

20

In terms of tx, what do you do when you suspect HIT?

STOP HEPARIN
use direct thrombin inhibitor (hirudin, argatroban, bivalirudin, dabigatran)

21

How is HIT ab detected?

ELISA

22

What is the pathogenesis of HIT?

Ab to heparin-PF4 complex resulting in activation of platelets

23

What is the complication of HIT?

thrombosis

24

How is hirudin cleared?

kidney

25

How is argatroban cleared?

liver

26

What is bivalirudin approved for?

use in coronary angioplasty but has been used in HIT tx

27

What is notable about dabigatran?

oral DTI, is irreversible/does not have an"antidote"