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40 Cards in this Set
- Front
- Back
What blood disorder is characterized by a deficiency of Factor VII:C? |
Hemophilia A |
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What is the most common factor deficiency in the US? |
Hemophilia A |
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Are vWF affected in Hemophilia A? |
No, vWF is not impaired, only VIII which prevents a strong platelet plug from forming |
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What is the reference range for clinical bleeding?
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50-150%
30% or less factor VIII activity indicates Hemophilia A
Can be mild, moderate, severe |
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What is the bleeding time, PT, and aPTT results for a patient with Hemophilia A
How would you confirm someone had Hemophilia A? |
Bleeding time- Normal PT-normal aPTT- increased
Confirm with factor VIII assay |
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What can cause acquired VIII deficiency? |
DIC
Liver disease |
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How is Hemophilia A treated? |
Purified factor VIII:C
Synthetic DNA-recombinant VIII:C
Cryoprecipitate- not ideal since anti-viral processing is not possible
DDAVP- can increase VIII in mild cases -may stimulate synthesis or release by liver |
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Hemophilia B is caused by a deficiency of what factor? |
Factor IX |
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What is the second most common factor deficiency in the US? |
Hemophilia B |
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What is the bleeding time, PT, and aPTT in a patient with Hemophilia B?
How would you confirm Hemophilia B diagnosis? |
Bleeding time-normal PT-normal aPTT-increased
Confirm with Factor IX assay |
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What can cause an acquired Factor IX deficiency? |
DIC Liver disease Vitamin K deficiency Oral anticoagulants |
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How is Hemophilia B treated? |
Factor IX concentrate
Vitamin K dependent concentrate
FFP for minor bleeds |
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Afibrinogenemia is characterized by what? |
Absence or very low fibrinogen |
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Hypofibrinogenemia is characterized by what? |
Fibrinogen levels less than 100mg/dL |
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Dysfibrinogenemia is characterized by what? |
Disfunctional fibrinogen |
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What are the results of BT, PT, aPTT, TT, RT, Fibrinogen activity, Fibrinogen antigen, and platelet aggregation in Afibrinogenemia? |
BT, PT, aPTT, TT, RT, - abnormal
Fibrinogen activity- low or undetectable
Fibrinogen antigen- Low or absent
Platelet aggregation- abnormal |
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What are the results of BT, PT, aPTT, TT, RT, Fibrinogen activity, Fibrinogen antigen, and platelet aggregation in Hypofibrinogenemia? |
BT- normal
PT, aPTT, TT, RT, - abnormal
Fibrinogen activity- low
Fibrinogen antigen- Low
Platelet aggregation-normal |
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What are the results of BT, PT, aPTT, TT, RT, Fibrinogen activity, Fibrinogen antigen, and platelet aggregation in Dysfibrinogenemia? |
BT-normal
PT, aPTT, TT, RT, - abnormal
Fibrinogen activity- normal or low
Fibrinogen antigen- normal or increased
Platelet aggregation- normal |
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What can cause an acquired fibrinogen deficiency? |
DIC
Fibrinogenolysis
Liver disease |
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What causes Hyperfibrinogenemia? |
Trauma, Pregnancy, Tissue Inflammation
Physiological stresses can cause fibrinogen to increase Fibrinogen is an acute phase reactant |
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What clinical symptoms appear in individuals with Prothrombin deficiency?
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Factor II deficiency Heterozygotes- usually asymptomatic Homozygotes- bleeding
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What can cause acquired prothrombin deficiency? |
DIC Liver disease Vitamin K deficiency Oral anticoagulants |
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What symptoms do Factor V deficient people exhibit?
What can cause acquired deficiency? |
Only homozygotes exhibit bleeding
DIC, Liver disease |
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Factor VII deficient patients exhibit what symptoms?
Causes of acquired deficiency? |
Homozygotes have symptomatic bleeding
DIC, liver disease, vitamin K deficiency, oral anticoagulants |
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Factor X deficient patients exhibit what symptoms?
Causes of acquired deficiency? |
Heterozygotes- mild bleeding Homozygotes- severe bleeding
DIC, liver disease, vitamin K deficiency, oral anticoagulants Amyloidosis deposits of amyloid in organs, adsorbs X |
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Factor XI deficiency is also known as what? Symptoms? Treatment? Causes of acquired deficiency? |
Hemophilia C Homozygotes-bleeding Only contact factor defic. that bleeds Treatment unnecessary except FFP if surgery
DIC, Liver disease |
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Why do factor XII deficient patients have an increased APTT but not show signs of bleeding? |
The body can activate the coagulation cascade through the alternative Extrinsic Pathway activating XI
The APTT test requires XII to activate coagulation cascade so test time is prolonged |
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Why do factor XII deficient patients tend to have thrombosis problems?
What can cause acquired factor XII deficiencies? |
Insufficient activation of plasmin, thus insufficient breakdown of clots
DIC, Liver disease |
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What symptoms do PK deficient patients exhibit? |
No bleeding though APTT is increased
May lead to thrombosis and require antithrombotic therapy |
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What symptoms do HMWK deficient patients exhibit? |
Clinically asymptomatic though APTT increased
May lead to thrombosis and require antithrombotic therapy |
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What symptoms do Factor XIII deficient patients exhibit? |
Umbilical stump bleeding Poor wound healing Bruises resolve slowly Excessive scar formation Cranial hemorrhage |
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How common is Factor XIII deficiency? |
65 families, very very rare |
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What does DIC stand for? When does it occur? |
Disseminated Intravascular Coagulation (and secondary fibrinolysis)
Acute episode whenever there is overwhelming stimulation of coagulation |
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Most lab test are prolonged or low for both fibrinolysis and fibrinogenolysis. What are the three tests that differentiate the two? |
D-dimers are positive in fibrinolysis Plt count is low in fibrinolysis (normal in fibrinogenolysis) Red cell destruction is seen in fibrinolysis |
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How is DIC treated? |
Remove the cause (dead fetus, infection, trauma) Stop clotting-heparin (depends on ATIII level) Replace factors-FFP Consider antifibrinolytic agent if bleeding doesn't stop |
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What is another term for Chronic DIC? When is it seen? What are the symptoms? What is the treatment? |
Compensated DIC Cirrhosis and metastatic cancer patients Less critical bleeding/ more diffuse thrombosis Slower progression Treat underlying cause
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Why is the liver so important to coagulation? What happens when someone has liver disease? |
Produces all factors, plasminogen, AT-III, and alpha2 antiplasmin
-Deficiency of factors and inhibitors -Dysfunctional factors and inhibitors -Impaired clearance of activated factors -Accumulate plasminogen activators -contributes to DIC |
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What symptoms are seen in those with renal disease? |
Loss of some factors, AT-III, and Protein C in urine
Uremic patients have decreased platelets and impaired platelet function
DIC- fibrin deposits result in renal damage |
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Vitamin K deficiency results in a deficiency of what factors? |
II, VII, IX, X
Protein C
-Anything vitamin K dependent |
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What issues can arise from massive transfusions? |
Storage of labile factors- lose V and VIII
Citrate Toxicity-only in newborns, give Ca2+
Thrombocytopenia- plts lose viability in stored blood |