Disorders of Hemostasis Flashcards
Hemophilia A and B
- Deficiency in Factor 8 of intrinsic clotting cascade. Generally congenital but can be from autoantibody (use) mixing studies to determine. B is from Factor 9 Deficiency.
- Presents with deep tissue and joint bleeds. Clot formation occurs but is weak and gel like “liver clot”. Generation of “Target Joints” where bleeding occurs more than 6 times in a year and causes osteoarthritic changes, can cause gait dysfunction and cycle.
- Labs will show an elevation in PTT and an absence or dysfunction of factor 8. Mixing studies will tell if it is from anitbody or defect. Bleeding time is variable, but can be normal.
- Treated with Factor 8. From plasma is cheaper but dirty. Recombinant is clean but expensive.
Disseminated Intravascular Coagulation (DIC)
- Activation of the clotting cascade through the endothelial damage or elevations in the level of Tissue Factor (Tissue Thrmoboplastin). Leads to fibrin clots in small vessels and a consumption of clotting factors
- Presents with many small clots in microvascular that can lead to necrosis and infarcts. Brain, Lungs, Kidneys, Heart, commonly effected. Sequale can be variable because of Hemorrhage risk. Most common causes are Pregnancy (TF in amniotic Fluid), Trauma, Sepsis, neoplasm.
- Labs will show an elevation in PT, PTT, and likely bleeding time with varying degrees of thrombocytopenia. Consumption of factors.
- Most important therapy is to remove the cause (deliver baby etc.). Then balancing act between bleeding and clotting risk. DO NOT GIVE PLATELETS
Von Willenbrand Disease
-Caused by defects in vWF. Type 1 (AD) is decreased quantity of functional vWF. Type 2A (AD) is loss of function mutation, 2B (AD) is gain of function mutation. Type 3 is absence. vWF also stabalizes factor 8, so type 3 (AR) will have hemophilia A. vWF levels are variable with estrogen and infection. Menorrhagia is common because of decrease in estrogen at time of menses.
-Presentation can be variable, 1% of population carries defect. Mennohagia is classic symptom along with epistaxis.
-Labs will show normal platelet count with elevations in ristocetin assay. May also show increases in PTT because of factor 8 stabilization. May show decreased levels of factor 8 for same reason.
-Treatment is DDVAP to cause release of vWF from wiebel pallade bodies in platelets and or repletion of factors. DDAVP is not indicated in type 2B because of clotting risk. Factors for type 3 and 2B
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Bernard-Soulier
Glanzmanns
Bernard Soulier is dysfunction in gp1b preventing platelets from binding vWF. Causes an increase if Bleeding time with no effect on PT or PTT.
Glanzmann is a defect in gp2b3a, prevention of platelet coagulation through fibrinogen. Elevations in Bleeding time with normal PT and PTT.
Thrombotic Thrombocytopenia Purpura
a
Idiopathic Thrombocytopenia Purpura
a
Hemolytic Uremic Syndrome
a
Hepain Induced Thrombocytopenia
aa
Lupus Anticoagulant
a
Factor 5 Leiden
aa
Prothrombin Mutation
a
HELLPP
a
Antithrombin Mutation
a
Protein C and S Mutation
a
Homocysteinuria
a
