Fibrinolytic System: DIC

Question 1

Five components of the fibrinolytic system

Answer 1

• Plasminogen
• Plasmin
• Plasminogen activators
• Plasminogen and plasmin inhibitors
• Fibrinogen/fibrin

Question 2

Five substances in which plasmin is capable of digesting

Answer 2

The fibrinogen group (I, V, VIII, XIII) plus fibrin

Question 3

What is the general mode of action/function of plasminogen activators?

Answer 3

To convert plasminogen to plasmin

Question 4

What is the primary plasminogen activator and its source of origin?

Answer 4

Tissue Plasminogen Activator (TPA) and is found in the endothelial cells that line the vessels (fibrinolytic property of the vascular intima)

Question 5

What is the consequence of a plasminogen activator deficiency?

Answer 5

Thrombosis

Question 6

What is the general mode of action/function of plasminogen and plasmin inhibitors?

Answer 6

Serves as a check on fibrinolysis by forming an irreversible complex w/ plasminogen or plasmin

Question 7

What is the primary inhibitor of plasminogen?

Answer 7

Plasminogen Activator Inhibitor 1 (PAI-1)

Question 8

What is the primary inhibitor of plasmin?

Answer 8

α-2-antiplasmin

Question 9

What is the consequence of a deficiency in plasminogen?

Answer 9

Thrombosis

Question 10

What is the consequence of a deficiency in plasmin inhibitors?

Answer 10

Bleeding

Question 11

This is a substrate in which plasmin acts upon and involves hydrolytic digestion of this by plasmin to form soluble degradation products

Answer 11

Fibrinogen/fibrin

Question 12

Plasmin has the ability to degrade both fibrinogen and fibrin into a series of well characterized end products known as ____ and ____

Answer 12

• Fibrinogen Degradation Products (FDP)

- Fibrin Degradation Products (FSP)

Question 13

What are the two early degradation products?

Answer 13

Fragments X and Y

Question 14

What kind of clotting do fragments X and Y do when fibrin acts on them?

Answer 14

“Slow clotting”

Question 15

What are the two late degradation products?

Answer 15

Fragments D and E

Question 16

Fragments D and E have an ____ effect and don’t allow fibrin monomers to line up to form loose bonding

Answer 16

Antipolymerization

Question 17

What are the final split products generated from one fibrinogen molecule?

Answer 17

2D and 1E

Question 18

How are degradation products cleared from the body?

Answer 18

?

Question 19

This is an intermediate degradation product formed when plasmin acts upon fibrin that was transmitted through the action of XIIIa. It is formed because plasmin cannot degrade the cross-linked covalent bonds between the D domains.

Answer 19

D-Dimer

Question 20

Nomenclature for D-Dimer

Answer 20

DD or D2E

Question 21

Clinical significance of a positive D-Dimer

Answer 21

Indicates a clot was/is present

Question 22

Two synonyms for DIC (essay)

Answer 22

• Consumption coagulopathy

- Defibrination syndrome

Question 23

Seven clinical states associated w/ DIC (essay)

Answer 23

• OB “complications”
• Trauma
• Sepsis
• Intravascular hemolysis
• Liver disease
• Promyelocytic leukemia
• Burn patients

Question 24

What is the consequence of uncontrolled formation and deposition of fibrin?

Answer 24

Leads to thromboses

Question 25

Six coagulation components consumed in clotting

Answer 25

I, II, V, VIII, XIII, platelets

Question 26

What is the consequence of the secondary activation of the fibrinolytic system?

Answer 26

Leads to bleeding

Question 27

Five coagulation components that are digested by plasmin

Answer 27

I, V, VIII, XIII, fibrin

Question 28

Clinical presentation of DIC

Answer 28

- Multiple site bleeding - Epistaxis - Hematuria - Oozing from intravascular sites - Petechiae/purpura - Renal failure (due to free hemoglobin)

Question 29

Treatment for DIC

Answer 29

- Treat underlying condition - FFP and/or platelet txns - Heparin therapy - Antifibrinolytic therapy (AMICAR)

Question 30

Results of CBC w/ DIC

Answer 30

- Schistocytes | - Decreased platelets

Question 31

Results of a PT and APTT in DIC

Answer 31

Prolonged PT and APTT

Question 32

Results of a fibrinogen in DIC

Answer 32

Decreased

Question 33

Results of a platelet count in DIC

Answer 33

Decreased count

Question 34

Four confirmatory tests for DIC

Answer 34

- Thrombin clotting time (TCT) - Reptilase test - FDP/FSP - D-Dimer

Question 35

Thrombin clotting time - Principle - Expected result

Answer 35

- ? | - Prolonged b/c it takes longer for fibrinogen to form a fibrin clot

Question 36

Repitlase time - Principle - Expected result

Answer 36

- ? | - Prolonged, adding reptilase instead of thrombin to plasma

Question 37

FDP/FSP - Principle - Expected result

Answer 37

- ? | - Positive, more split products and acts as an antithrombin

Question 38

D-Dimer - Principle - Expected result

Answer 38

- ? | - Positive, fibrinogen is influenced by XIII and DDs are left over

Question 39

Three conditions in which primary fibrinolysis may occur?

Answer 39

- Open heart surgery - Metastatic prostate cancer - Lightening strike patients

Question 40

Blood smear evaluation | - DIC vs. primary fibrinolysis

Answer 40

- DIC: schistocytes | - Primary fibrinolysis: no schistocytes

Question 41

D-Dimer | - DIC vs. primary fibrinolysis

Answer 41

- DIC: positive | - Primary fibrinolysis: negative

Question 42

Platelet count | - DIC vs. primary fibrinolysis

Answer 42

- DIC: decreased (consumed in clotting) | - Primary fibrinolysis: Normal

Question 43

Blood smear | - DIC vs. TTP

Answer 43

- DIC: schistocytes | - TTP: schistocytes

Question 44

D-Dimer | - DIC vs. TTP

Answer 44

- DIC: positive | - TTP: negative

Question 45

Platelet count | - DIC vs. TTP

Answer 45

- DIC: decreased | - TTP: decreased

Question 46

PT | - DIC vs. TTP

Answer 46

- DIC: prolonged | - TTP: usually normal

Question 47

APTT | - DIC vs. TTP

Answer 47

- DIC: prolonged | - TTP: usually normal

Question 48

in TTP, microthrombi are deposited through the body in microcirculation composed primarily of ____, not fibrin like in DIC. This is PRIMARY hemostasis.

Answer 48

Platelets

Question 49

This enzyme is synthesized in the kidney and is secreted mainly by epithelial cells in the urinary tract

Answer 49

Urokinase

Question 50

Which factor is derived from contact activation

Answer 50

XIIa