hypercoagulability Flashcards
what does antithrombin inhibit?
1) Thrombin
2) Factor 9a
3) Factor 10a
What does the Factor V Leiden mutation do?
it blocks a site for which aPC binds to factor 5a. This increases risk of thromboembolism 5-7 fold
What accelerates the inhibitor effect of antithrombin?
heparin sulfate glycosoaminoglycans on the endothelial surface
what would result if someone had a deficiency of antithrombin, protein S or protein C ?
increases the potential for thrombosis to proceed unchecked in normal vessels.
What blood groups have a higher risk for thrombosis? Why?
blood groups A, B or AB. Because they have a longer circulating half-life of vWF and 25% higher plasma level.
what is a lupus anticoagulant?
antibodies that interfere with phospholipid-dependent clotting assays such as aPTT
how are anticardiolipid antibodies detected ?
ELISA method
What is a significant Titre report for anticardiolipin antibodies?
high-titre IgG anticardiolipin antibodies >40 GPL units
What is a non significant report for anticardiolipin antibodies
low-titre IgM anticardiolipins
how does antiphospholipid syndrome manifest?
1) venous or arterial thrombosis
2) recurrent (late as opposed to early - due to placental thrombosis) pregnancy loss
what are other clinical manifestations associated with autoantibodies associated with antiphospholipid syndrome?
1) ITP
2) livedo reticularis (a mottled, bluish, lacey-pattered rash)
What are the antiphospholipid antibodies?
1) lupus anticoagulant
2) anticardiolipin antibody
3) anti-beta2 glycoprotein I
What is antiphospholipid syndrome ?
thrombosis OR recurrent pregnancy loss PLUS persistent antiphospholipid antibody
is cancer a risk factor for venous thromboembolism?
yes
What should be suspected in a patient with idiopathic DVT or PE?
look for malignancy because 5-10% are found to have cancer within a year of diagnosis of VTE
