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30 Cards in this Set

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What are the events in primary, secondary, and tertiary hemostasis?
Primary Hemostasis:
- Platelet adhesion
- Platelet aggregation
- Platelet plug formation

Secondary Hemostasis:
- Coagulation pathway

Tertiary Hemostasis:
- Crosslinking of fibrin and factor 13
- Fibrinolysis
In Primary hemostasis, vWF binds to exposed collagen, what platelet protein binds to vWF?
GP1B/V/IX binds vWF
What are in alpha granules of platelets? (7)
P-selectin
PDGF
PF4
Platelet fibrinogen
Thromboglobulin
Thrombospondin
vWF
What are in delta (dense) granules of platelets? (4)
ADP
ATP
Serotonin
Ca2+
After the platelet plug is formed, what platelet protein is involved in platelet aggregation? What binds to the protein?
In platelet aggregation, GPIIb/IIIa binds fibrinogen.
In addition to converting fibrinogen to fibrin, what else does factor IIa (thrombin) do?
Thrombin activates F5, 8, 11, 13.
What is the formula for calculating INR?
INR = [(Patient PT)/(Normal mean PT)]^ISI
What does ISI stand for?
ISI = International Sensitivity Index (related to amount of tissue factor in reagent)
What factor deficiency presents with normal PT and PTT?
Factor 13 deficiency
What is the purpose of reptilase time?
Reptilase time:
1. A way of getting around heparin contamination. RT is not increased even if there is heparin.
2. An increased RT indicates dysfibrinogenemia.
These classes of disorders do not have secondary phase with epinephrine and ADP in platelet aggregation studies.
Storage pool defects, aspirin
What is defect in Bernard-Soulier syndrome? What is the function of the defective protein?
Defect in GP1B/5/9. GP1B/5/9 binds to vWF during platelet adhesion in primary hemostasis.
What is the typical finding in Bernard-Soulier?
PT
PTT
BT
Platelet aggregation study
Plt count
Blood smear
Clot retraction test
What is the typical finding in Bernard-Soulier?
PT: normal
PTT: normal
BT: increased
Platelet aggregation study: Everything (ADP, Epi, Collagen) is normal except ristocetin aggregation
Plt count: decreased
Blood smear: large platelets
Clot retraction test: normal
What is the defect in Glanzmann thrombasthenia? What is the function of the defective protein?
Defect in GP2b/3a. GP2b/3a binds to fibrinogen in platelet aggregation during primary hemostasis.
What is the typical finding in Glanzmann thrombasthenia?
PT
PTT
BT
Platelet aggregation study
Plt count
Blood smear
Clot retraction test
What is the typical finding in Glanzmann thrombasthenia?
PT: normal
PTT: normal
BT: increased
Platelet aggregation study: the only normal thing is ristocetin
Plt count: normal
Blood smear: normal
Clot retraction test: no retraction
This autosomal dominant disease due to mutated myosin heavy chain 9, is characterized by giant platelets and Dohle bodies in granulocytes on blood smear.
May-Hegglin anomaly
What is the defect in gray platelet syndrome?
No alpha granules
What syndrome lacks delta granules and has Swiss cheese platelets?
Hermansky-Pudlak syndrome
What is the only type of vWD treated by DDAVP?
Type 1
What is the defect in type 2b and pseudo-vWD?
2B: vWF with increased affinity for GP1b/5/9 (platelet receptor in adhesion of primary hemostasis) resulting in consumption of large vWF multimers without injury.

Pseudo-vWD: Defective GP1b/5/9 with increased affinity for vWF.
What is 2M vWD?
Defective vWF which can't bind GP1b/5/9 well.
What is 1 Bethesda unit?
1 BU = 50% activity of the factor

NOTE: 2 BU = 25%; 3 BU = 12.5%, etc...
What is the function of vitamin K and which are the vitamin K dependent factors?
Function: carboxylation of gluatmate residues to form gamma-carboxyglutamate residues.

K-dependent: 2, 7, 9, 10, C, S
What additive causes pseudothrombocytopenia? What does the smear look like?
EDTA, platelet satellitism
What is the typical triad of HUS?
Microangiopathic hemolytic anemia, thrombocytopenia, acute renal failure
What is the typical pentad of TTP?
Microangiopathic hemolytic anemia, thrombocytopenia, neurological symptoms, acute renal failure, fever
What is the defect in factor 5 Leiden?
Factor 5a is immune to inactivation by protein C.
What are the 2 most common mutations causing factor 5a to be immune to inactivation by protein C?
1. Factor V Leiden: glycine to arginine at 506 (G506R).

2. Factor V Cambridge: threonine to arginine at 306 (T306R).
What is the mechanism of heparin induced thrombocytopenia? What is the timeframe in which it develops?
Mechanism: IgG Ab to heparin PF4 complex in alpha granules

Timeframe: 5-8 days after starting unfractionated heparin
What makes vWF?
Megas and endothelial cells