Term
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Definition
| Autosomal dominant, mucosal bleeding, prolonged bleeding time |
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Term
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Definition
| X-linked recessive, hemarthrosis, normal bleeding time |
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Term
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Definition
| ecchymosis, epistaxis, gastrointestinal bleeds, menorrhagia, bleed after trauma, surgical bleeds |
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Term
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Definition
| In endoplasmic reticulum (endothelial cells, megakaryocytes) |
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Term
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Definition
| Weibel-Palade bodies - endothelial cells. Alpha granules- platelets |
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Term
| Platelet to platelet aggragation is mediated by |
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Definition
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Term
| VWF role associated with FVIII |
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Definition
| protects it from degradation by protein C, localized at injury site |
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Term
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Definition
| Partial quantitative deficiency of vWF: Most common, quantitative decrease in vWF by 50% . Structure is normal, concentration is decreased. F8 concentration will be lower. |
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Term
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Definition
| Virtual complete defeciency of VWF, marked clearance of FVIII (5-10%), severe bleeding |
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Term
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Definition
| Qualitative variants with decreased platelet-dependent function- absence of high and intermediate molecular weight multimers. Platelet binding is reduced, moderate to severe mucous bleeding. |
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Term
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Definition
| Qualitative variants with increased affinity for platelet G1b receptor. Gain of function mutation, spontaneous platelet binding,clearance of platelets and HMW VWF yeilds reduced VWF, thrombocytopenia, absent high molecular weight VWF |
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Term
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Definition
| Qualitative variants with markedly decreased affinity for factor VIII, called autosomal hemophilia since it is a factor 8 binding region mutation, causes reduced plasma factor 8, platelet binding is normal (normal bleeding time?) |
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Term
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Definition
| Qualitative variants with decreased platelet-dependent function-all multimers present: decreased or absent binding to PLT GP1b, normal binding to factor VIII (prolong bleed time) |
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Term
| VWD classification - platelet type |
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Definition
| Pseudo VWD, gain of function defect in PLATELET Gp1B vWF receptor, similar to type 2B, spontaneous binding to vWF, clearance of large multimers, decreased VWF and factor VIII, distinguished by mixing with normal plasma (PLT type causes aggregation, type 2b does not). Treatment is with normal platelets, VWF concentrates with severe bleeding |
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Term
| Difficulties in diagnosing VWD |
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Definition
| it is an acute phase reactant: elevated in illness, stress, pregnancy, excercise, normal variations in concentrations, differences due to blood type (type o has least concentration) |
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Term
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Definition
| Bleeding time, PTT, Ristocetin cofactor, factor VIII activity, vWF antigen, VWF analysis |
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Term
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Definition
| different age of presentation, absence of personal and family history of bleeding time, presence of hematoproliferative or autoimmune disorder. can be caused by antibodies to VWF, adsorption of VWF by malignant cells, increased VWF proteolytic degradation, decreased VWF synthesis |
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Term
| VWF role in TTP thrombotic thrombocytopenic purpura |
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Definition
| Synthesis after secretion- reduction of disulfide bonds, proteolysis by metalloprotease, enhanced by shear forces, ultrahigh MW vWF, VWF cleaving protease deficiency |
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