molecular basis of blood clotting disorders

Question 1

describe haemophilia

Answer 1

failure to clot = haemorrhage
mutations in coagulation factors (haemophilia A + B)
platelet disorders (VW disease)
collagen abnormalities

Question 2

describe thrombophilia

Answer 2

excessive clotting = thrombosis

• inherited = mutations in coagulation factors
• acquired = malignancy increases clotting factors

Question 3

what is disseminated intravascular coagulation

Answer 3

whole body clots = infection

depletion of clotting factors and platelets lead to bleeding

Question 4

list the 2 bleeding disorders

Answer 4

haemophilia A and B = swelling and bruising

von willerband disease = inherited. affects mucous membranes/ bleeding in gums

Question 5

describe excessive clotting

Answer 5

factor V5 leiden mutation = resistance to ADC, not inactivated. increases risk of DVT

antithrombin deficiency = thrombin, Ixa, Fxa, not inactivated. increases risk of DVT
protein c and s deficiency = increase risk of DVT

Question 6

what is virchow’s triad

Answer 6

alterations in constituents of blood
changes In normal blood flow
damage to endothelial layer

1. stasis
2. hyper coagulability
3. vessel wall injury

Question 7

symptoms of deep vein thrombosis

Answer 7

swelling
skin changes
superficial venous distension 
increased skin temp 
skin discolouration 
risk of pulmonary embolism

Question 8

describe disseminated intravascular coagulation

Answer 8

clotting and bleeding

in sepsis.
depletion of clotting factors and platelets = bleeding

Question 9

how do anticoagulants prevent more clots

Answer 9

e.g warfarin, heparin, direct oral anticoagulants

whereas,

thrombolytics/fibrinolysis reverse this
e.g plasminogen activators, tPA, streptokinase

Question 10

management of VTE: pre and post treatment

Answer 10

pre:

• clotting screen
• full blood count
• renal screen
• liver function test

post:
- DVT = anticoagulant

PE = thrombolysis
alteplase, streptokinase
followed by anticoagulant to prevent recurrence

bleeding complications can occur from anticoagulants