Pathophysiology of Coagulation Disorders

Question 1

What lab tests may be run in order to assess for platelet disorders?

Answer 1

Platelet count, peripheral blood morphology, platelet function tests, platelet aggreggation studies

Question 2

What is the function of desmopressin?

Answer 2

Synthetic analog of vasopressin that elevates VII & VWF levels in the blood

Question 3

Tissue factor is involved in what coagulation pathway?

Answer 3

Extrinsic pathway

Question 4

What is the MOA of warfarin?

Answer 4

Warfarin inhibits the Vitamin K reductase, thus preventing activation of Vitamin K-dependent clotting factors

Question 5

What is the body’s first response to tissue injury?

Answer 5

Vasoconstriction - followed by adhesion, activation, and aggregation

Question 6

What is Antiphospholipid Syndrome?

Answer 6

A systemic autoimmune disorder that causes the formation of abnormal clots. It is associated with thrombosis, pregnancy morbidity, and aPL antibodies

Question 7

What Factor is deficient in Hemophilia C?

Answer 7

Factor XI

Question 8

What clotting factors are Vitamin K-dependent?

Answer 8

II, VII, IX, X

Question 9

What is the function of Protein C and Protein S?

Answer 9

Protein S is a cofactor of Protein C. When bound together, they act as an anti-coagulant

Question 10

Von Willebrand Disease is what type of inherited platelet defect?

Answer 10

Adhesion defect

Question 11

What is VW Disease?

Answer 11

An autosomal dominant quantitative deficiency or functional abnormality in vWF

Question 12

True/False. The intrinsic coagulation pathway is quicker than extrinsic.

Answer 12

False. The extrinsic coagulation pathway occurs more quickly than intrinsic.

Question 13

Fibrinogen is also known as…?

Answer 13

Coagulation Factor I

Question 14

A clinician wants to test if a patient has a defect in the clotting cascade. What tests can they run to determine if the issue is within the cascade or not?

Answer 14

PT (Extrinsic Pathway)
PTT (Intrinsic Pathway)

A normal test indicated the clotting cascade is adequate and the bleeding disorder is due to another cause (ex: drug inhibitor)

Question 15

Coagulation Factor III is also known as…?

Answer 15

Tissue Factor

Question 16

Prothrombin is also known as…?

Answer 16

Coagulation Factor II

Question 17

True/False. Warfarin is recommended for use in emergencies or with current clots.

Answer 17

False. Warfarin can take some time to become effective. Heparin is used for current clots and surgeries.

Question 18

Where are many anti-coagulant factors synthesized?

Answer 18

Liver (Protein C, Protein S, anti-thrombin)

Question 19

Platelet disorders related to drug use, disease, or surgical procedures are termed…?

Answer 19

Acquired platelet disorders

Question 20

What are the four categories of inherited platelet defects?

Answer 20

Recruitment defects, secretion defects, cohesion defects, adhesion defects

Question 21

What is the effect of a gain-of-function mutation in the prothrombin gene?

Answer 21

Responsible for hypercoagulability state and thus increased clotting

Question 22

What is the most common acquired thrombotic disorder?

Answer 22

Antiphospholipid Syndrome (APS)

Question 23

The body exists in a homeostatic balance between fibrinolysis and coagulation. What natural anti-coagulant prevents the continuous activation of Coagulation Factor III?

Answer 23

Tissue Factor Pathway Inhibitor (TFPI)

Question 24

What is the mechanism of Factor V Leidan?

Answer 24

FVL renders Factor V insensitive to protein C, which acts as an anti-coagulant. The result is increased clotting

Question 25

Factor IX is deficient in what type of hemophilia?

Answer 25

Hemophilia B

Question 26

How does Type 2 VW Disease differ from Types 1 & 3?

Answer 26

Both Types 1 & 3 are quantitative disorders, while in Type 2, there is enough VWF but it functions abnormally

Question 27

Thrombophilia is a predisposition to form blood clots. What three factors must be present for thrombosis?

Answer 27

Flow stasis, endothelial damage, hypercoagulable state

Question 28

What are the most common inherited bleeding disorders?

Answer 28

Haemophilia A, Haemophilia B, Haemophilia C, and VW Disease

Question 29

Hemophilia A is due to a deficiency of what factor?

Answer 29

Factor VIII