Coagulation disorders - Secondary hemostasis Flashcards
(124 cards)
1
Q
The intrinsic pathway of clot formation is activated by this
A
Collagen exposure –> activates Factor XII
2
Q
The extrinsic pathway of clot formation is activated by this
A
Tissue factor release –> activates Factor VII
3
Q
In the intrinsic pathway of clot formation, collagen activates this molecule
A
Factor XII
4
Q
In the extrinsic pathway of clot formation, Tissue Factor activates this molecule
A
Factor VII
5
Q
Is the intrinsic or extrinsic pathway of clot formation activated by collagen exposure?
A
Intrinsic
6
Q
Is the intrinsic or extrinsic pathway of clot formation activated by Tissue Factor release?
A
Extrinsic pathway
7
Q
Is Factor XII activated in the intrinsic or extrinsic clotting pathway?
A
Intrinsic
collagen activates Factor XII
8
Q
Is Factor VII activated in the intrinsic or extrinsic clotting pathway?
A
Extrinsic
Tissue Factor activates Factor VII
9
Q
The intrinsic and extrinsic clotting pathways converge by both activating this molecule
A
Factor X
10
Q
The intrinsic and extrinsic pathways of clotting both converge to activate Factor X, which then activates this molecule
A
Prothrombin (II) –> thrombin (IIa)
11
Q
This molecule in the coagulation cascade activates prothrombin to thrombin
A
Factor Xa
12
Q
In the coagulation cascade, thrombin cleaves this molecule
A
Fibrinogen –> Fibrin
13
Q
In the coagulation cascade, thrombin cleaves this molecule
A
fibrinogen –> fibrin
14
Q
This molecule cross-links fibrin polymers
A
Factor XIII
15
Q
What is the function of Factor XIII in the coagulation cascade?
A
Cross-links fibrin polymers
16
Q
These two molecules in the intrinsic pathway of clotting convert Factor X –> Xa
A
Factor IXa and VIIIa
17
Q
These two molecules in the common pathway of clotting convert prothrombin to thrombin (IIa)
A
Factor Xa and Va
18
Q
Thrombin (IIa) cleaves fibrinogen to fibrin, as well as activates these three other factors
A
V
VIII
II
19
Q
Prothrombin time can be measured by adding this molecule
A
Extrinsic tissue factor
so assesses extrinsic pathway
20
Q
Prolonged PT (prothrombin time) indicates a defect in this pathway
A
Extrinsic pathway, including warfarin
21
Q
Does PT or PTT assess the functioning of Factor VII?
A
PT
prolonged PT = defect in extrinsic pathway
22
Q
Does PT or PTT assess the functioning of Factor IX?
A
PTT
prolonged = defect in intrinsic pathway
23
Q
Does PT or PTT assess the functioning of Factor VIII?
A
PTT
prolonged = defect in intrinsic pathway
24
Q
To measure PTT (Partial thromboplastin time), this molecule is added
A
Kaolin
activates Factor XII, and time to clot is measured
25
In determining PTT (Partial thromboplastin time), Kaolin (negative charge) is added, which activates this molecule
Factor XII
26
Thrombin time measurement essentially isolates the function of this molecule
Fibrinogen
27
Thrombin time is prolonged in this type of disorder
Dysfibrinogenemias
(or heparin presence)
28
This type of lab test determines if prolonged PTT is due to an inhibitor or factor deficiency
Mixing studies
29
Does a factor deficiency or an inhibitor result in prolonged PTT during mixing studies?
Inhibitor
Normal plasma is mixed with patient plasma in 1:1 ratio
Inhibitor will inhibit normal plasma → PTT remains prolonged
Deficiency will be corrected by normal plasma
30
What will be the result of mixing studies in a factor deficiency?
Deficiency will be corrected by normal plasma = normal PTT
31
What will be the result of mixing studies if the patient has an inhibitor problem?
PTT remains prolonged
inhibitor still inhibits normal plasma
32
This lab test assesses if the patient is able to cross-link fibrin polymers
Urea clot stability
33
What will be the result of a Urea clot stability test if the patient can cross-link fibrin polymers?
Cross-linked clot will remain clotted
34
What will be the result of a Urea clot stability test if the patient can NOT cross-link fibrin polymers?
Clot without cross-linking will dissolve
35
Urea clot stability tests the functioning of this molecule
Factor XIII
36
This lab test can be run to test for Factor XIII functioning
Urea clot stability
37
In the lab test for Factor XIII, aged clot is incubated in high strength solution of this
Urea
38
Deep hematomas are symptoms of this type of bleeding
Coagulation type
39
Hemarthrosis is a symptom of this type of bleeding
Coagulation type
40
Delayed bleeding is a symptom of this type of bleeding
Coagulation type
41
Rebleeding after injury/surgery/dentistry is a symptom of this type of bleeding
Coagulation type
42
This is an X-linked recessive deficiency or absence of Factor VIII
Hemophilia A = Factor VIII deficiency
43
Hemophilia A is an X-linked recessive deficiency/absence of this molecule
Factor VIII
44
Hemophilia A (Factor VIII deficiency) has this inheritance pattern
X-linked recessive
Affects males and homozygous females
45
A newborn with intracranial bleeding during birth, or an adult with spontaneous bleeds such as hemarthrosis and deep soft tissue, could have this type of disorder
Bleeding disorder -- Factor VIII or IX deficiency
46
What are the results of PTT and PT testing in a patient with Hemophilia A (Factor VIII deficiency)?
PTT prolonged (intrinsic pathway)
PT normal
47
This is a complication of Hemophilia A (Factor VIII deficiency) that results from hemarthrosis
Degenerative joint disease --> synovial proliferation
Early onset osteoarthritis
48
Early onset osteoarthritis can occur in Hemophilia A (Factor VIII deficiency) due to this clinical finding
Hemarthrosis
49
This is an X-linked recessive deficiency or absence of Factor IX
Hemophilia B
"Christmas disease"
50
Hemophilia B (or "Christmas disease") is an X-linked recessive deficiency or absence of this molecule
Factor IX
51
Hemophilia B (Factor IX deficiency) has this inheritance pattern
X-linked recessive
52
What are the results of PTT and PT testing in a patient with Hemophilia B (Factor IX deficiency)?
PTT prolonged (intrinsic pathway)
PT normal
53
Do mixing studies correct Hemophilia A and B?
Yes, since they are due to deficiencies
54
This clotting factor of the intrinsic pathway is also reduced in Vitamin K deficiency
Factor IX
55
Factor IX antigen and activity levels are also reduced in this vitamin deficiency
Vitamin K
56
The neonatal period has physiologic low levels of production of this clotting factor of the intrinsic pathway
Factor IX
57
In this acquired condition, usually of the elderly, autoantibody is formed against this clotting factor
Same lab testing results as hemophilia A/B (prolonged PTT, normal PT), but mixing studies do NOT correct
Acquired Factor VIII inhibitor
58
This is the typical patient with Acquired Factor VIII inhibitor
Elderly
59
This is a very rare autosomal recessive disorder of defective fibrin cross-linking
Factor XIII deficiency
60
Factor XIII deficiency has this inheritance pattern
Autosomal recessive
61
A patient with this condition may have delayed bleeding from umbilical cord stump, delayed wound healing, and recurrent miscarriage
Factor XIII deficiency
62
What is the result of urea clot stability test in Factor XIII deficiency?
Clot dissolves
(due to defective fibrin cross-linking)
63
Factor Va is a cofactor for this conversion
Prothrombin --> thrombin
64
This enzyme degrades Factor Va
Protein C
65
This is a cofactor involved in the degradation of Factor Va
Protein S
66
Protein C and S are an enzyme and cofactor that degrade this molecule
Factor Va
67
Both Protein C and S are made in this location
Liver
Liver disease and Warfarin diminish ability to synthesize these proteins
68
Synthesis of Protein C and S require this vitamin
K
69
Protein C cleaves Factor Va, and this occurs in this location
Surface of an intact endothelial cell
70
Thrombin binds this molecule, and along with Protein C degrades Factor Va
Thrombomodulin
71
This is a large molecule which inactivates thrombin
Antithrombin
72
Endothelial cells normally have these bound to the surface, which bind antithrombin
Glycosaminoglycans
73
When antithrombin is bound to these on endothelial surface, it inactivates thrombin (also IXa, Xa, XIa, XIIa)
Glycosaminoglycans
74
This is a GAG-like molecule that binds antithrombin and thrombin together, and potentiates antithrombin activity
Heparin
75
Heparin potentiates the activity of this
Antithrombin
76
Heparin binds antithrombin like this type of molecule normally would
Glycosaminglycans
77
This lab test determines the therapeutic level of heparin, especially LMWH
Anti-Xa activity
78
Anti-Xa activity is used to determine therapeutic level of heparin, especially this type
LMWH
79
This is an inherited Factor V mutation that causes activated protein C resistance
Factor V Leiden
80
Factor V Leiden is an inherited mutation that causes this
Activated Protein C resistance
81
Does Factor V Leiden result in increased or decreased Factor Va activity?
Increased
due to activated protein C resistance
82
This is the most common inherited thrombophilia
Factor V Leiden
83
Factor V Leiden is most common in this patient population
Northern European
84
A young adult with a family history of venous thrombosis, who is now having thromboembolism in their retinal vein, may have this condition
Factor V Leiden
85
This is the lab test for Factor V Leiden
PTT
(with and without activated protein C)
86
In this condition, PTT fails to prolong after addition of activated protein C
Factor V Leiden
87
What is the result of PTT testing in Factor V Leiden?
PTT fails to prolong after addition of activated protein C
88
Protein C or S deficiency have this inheritance pattern
Autosomal dominant
89
Warfarin inhibits enzymes dependent on this molecule
Vitamin K
Factors II, VII, IX, X
Protein C and S
90
What results in transient hypercoagulability with warfarin use?
Precipitous fall in Protein C
91
Patients most at risk of warfarin induced skin necrosis have this condition
Protein C deficiency
92
Warfarin induced skin necrosis involves these types of tissues
Fatty tissues (breasts, thighs)
93
Antithrombin deficiency has this inheritance pattern
autosomal dominant
94
When testing for Antithrombin deficiency, why is timing of test for AT activity critical?
Because AT is consumed with clotting
Must not be temporally close to thrombosis, DIC, surgery, heparin therapy, etc
95
This is a genetic polymorphism of Factor II causing elevated prothrombin level
Prothrombin G20210A
96
Does Prothrombin G20210A polymorphism cause increased or decreased prothrombin level?
Elevated
97
What is the result of PT testing in Prothrombin G20210A?
May be normal
Genetic testing is required
98
What is the diagnostic test for Prothrombin G20210A?
Genetic testing is required
PT may be within normal range
99
This condition produce a prolonged PTT and clinical thrombophilia
Antiphospholipid syndrome
100
Antiphospholipid syndrome is most common in this type of patient
Women; patients with SLE
101
When cells are damaged, they release phospholipids, which activate these clotting factors
VII and XII
102
These are used to accelerate clotting reaction in clotting test (PTT)
Phospholipids
103
What causes platelet activation in Antiphospholipid syndrome?
Autoantibodies bind phospholipids on platelets
104
How does Antiphospholipid syndrome cause a prolonged PTT?
Autoantibodies interfere with in vitro clotting
105
What is the result of PTT testing in Antiphospholipid syndrome?
Prolonged
autoantibodies interfere with in vitro clotting
106
Antiphospholipid syndrome can cause platelet thrombus. Is this often venous or arterial?
Arterial
one of the few conditions that causes arterial thrombus
107
Does Antiphospholipid syndrome result in low or high platelets?
Low
108
A patient with thrombophilia with a history of miscarriages, may have this condition
Antiphospholipid syndrome
109
These are the two main clinical criterion for diagnosis of Antiphospholipid syndrome
Vascular thrombosis (arterial, venous, or small vessel)
Pregnancy morbidity
110
What is the diagnostic criteria for Antiphospholipid syndrome?
At least 1 clinical criterion (vascular thrombosis, pregnancy morbidity) and 1 lab criterion (antibody)
111
These 3 different autoantibodies may be seen in Antiphospholipid syndrome
Anti-cardiolipin antibody
Anti-beta 2 GPI
Lupus anticoagulant (anti-phospholipid)
112
This is the most common test for lupus anticoagulant (anti-phospholipid antibody) in Antiphospholipid syndrome
dRVVT
(clotting test with phospholipid as rate-limiting reagent)
113
This is the last confirmation test for diagnosis of Antiphospholipid syndrome
Mixing study
114
Increased level of this leads to accelerated atherosclerosis and increased thrombosis risk
May be inherited or acquired through diet
Controversial whether testing is appropriate
Hyperhomocysteinemia
115
In dysfibrinogenemia, increased activity may have this effect
Thrombosis
116
In dysfibrinogenemia, decreased activity may have this effect
Bleeding
117
Acquired defect in fibrinogen is common in this condition, due to abnormal post-translational alterations
Liver failure
118
Most inherited forms of dysfibrinogenemia lead to this
Bleeding
(due to decreased fibrinogen activity)
119
What is the result of thrombin time in dysfibrinogenemia?
Prolonged
120
Low factor V with normal/increased factor VIII indicates this
Liver disease
Will have high PT and PTT
121
What are the results of PT and PTT tests in liver disease?
Both high
122
Low levels of this clotting factor can result in bleeding umbilicus
Factor XIII
123
Urea clot stability assay is used to assess levels of this clotting factor
XIII
124
What is the result of PTT testing in a patient with low factor XII?
High PTT
