Disorders of coagulation Flashcards
Blood clotting disorders definition?
• Defects in the key components of clotting- Coagulation proteins, Platelets and Endothelium
What is haemophillia?
• Haemophilia - failure to clot leading to haemorrhage
o Mutations in coagulation factors (haemophilia A and B)
o Platelet disorders (von Willebrand disease)
o Collagen abnormalities (fragile blood vessels and bruising)
What is thrombophilia?
• Thrombophilia – excessive clotting leading to thrombosis
o Inherited: mutations in coagulation factors (DVT)
o Acquired: malignancy increases clotting factors e.g. tissue factor, thrombin factor 10 (DVT)
What is DIC?
• Disseminated intravascular coagulation (DIC) – whole body clots
o Infection
o Depletion of clotting factors and platelets leads to bleeding
o Coagulation and bleeding happening simultaneously
What is von Willebrand disease?
• von Willebrand disease- Inherited defect/deficiency in vWF- without this there is no platelet adhesion, activation and aggregation- increased risk of bleeding
What is Haemophillia B and A respectively?
- Haemophilia B (20%)- Mutated FIX (9)
* Haemophilia A (80%)- Mutated FVIII (8)
What will a mutation in factor 8a and 9a result in?
Bleeding
What is the symptoms of haemophillia?
• Haemophilia- massive haemorrhage, gross swelling from acute hemarthroses of the knee joint
What are the symptoms of VWF
• VWF disease- affects mucous membrane, mostly mild but bleeding can vary in severity
Describe excessive clotting
Excessive clotting
• Factor V Leiden mutation
o Resistance to APC- inhibition of this anticoagulant pathway
o FVa is not inactivated- it’s not degraded still works
o Increases risk of DVT
What is antithrombin deficiency?
• Antithrombin deficiency
o Thrombin, IXa and FXa are not inactivated- these factors aren’t degraded
o Increases risk of DVT
What does protein C and S deficiency increase the risk of?
Protein C deficiency/ Protein S deficiency
o Increases risk of DVT
What are the causes of DVT?
o Alterations in the constituents of the blood
o Changes in normal blood flow
o Damage to the endothelial layer
What are symptoms of DVT?
• Symptoms- all due to obstruction of venous return o Pain & tenderness of veins o Limb swelling o Superficial venous distension o Increased skin temperature o Skin discoloration
What do the symptoms of DVT reflect?
o All reflect obstruction to the venous drainage
o Increased risk of pulmonary embolism
If DVT is above the knee what is it more at risk of?
o If DVT is above knee there’s more risk of DVT embolising
What makes up virchows triad and leads to thrombosis?
- Vessel wall injury
- Stasis- reduced venous flow
- hypercoagulability
What is DIC?
- As in sepsis (body’s response to an infection injures its own tissues and organs)
- Depletion of clotting factors and platelets leads to bleedin
What is treatment of these disorders?
Do they need regulation?
What do thrombolytics and fibrinolytics do?
Treatment
• Warfarin needs to be regulated
• Thrombolytics and fibrinolytics degrade clot
•
What is VTE, PT, TT, PTT?
VTE = venous thrombosis embolism
• PT = measures deficiency in factors 8,10,5 and fibrinogen
• Common cause of the above deficiency is liver disease, warfarin therapy and DIC
• TT =. Deficiency or abnormality of fibrinogen due to heparin therapy
• PTT = deficiency of 8,9,11,12,10,5, prothrombin and fibrinogen due to Christmas disease and haemophilia
What are the complications of treatments?
Complications of these treatments:
o bleeding- like in node and clots in eye- these are minor
o Severe bleeds include intracerebral bleeds, happen in brain, are larger
What do anticoagulants prevent?
How are VTE managed?
