heritable blood disorders

Question 1

what is haemostasis

Answer 1

balance between bleeding and clotting

Question 2

what will a breech in vaso-integrity cause

Answer 2

vasoconstriction and activation platelets at injury then aggregation to form a plug
coagulation then activated = fibrin plug

Question 3

during platelet activation what factors are released

Answer 3

thromboxane A2 - more platelet aggregation
vWF
fibrinogen

Question 4

what platelets protein receptors are from vWF and fibrinogen

Answer 4

vWF - glycoprotein 1b9

fibrinogen - glycoprotein 2b3a

Question 5

what happens when vWF and fibrinogen binds to platelet proteins receptors

Answer 5

vWF - acts as glue which allows platelets to adhere to collagen of epithelium

fibrinogen - allows platelets to stick to each other

Question 6

how do these drugs affect platelet aggregation
clopidegral
aspirin

Answer 6

clopidegral stops platelet activation

aspirin stops CDX and thromboxane release

Question 7

describe the extrinsic coagulation pathway

Answer 7

activated first
exposure of tissue factor activates VII, f VIIa activates X, Xa and Va activate prothrombin to produce thrombin from fibrinogen

Question 8

describe the intrinsic pathway

Answer 8

when blood gets involved with foreign object

XII activated which actauvtes XI and IX then follows extrinsic

Question 9

which factor is vital for fibrin

Answer 9

factor X

Question 10

describe the process of fibrinolysis

Answer 10

plasmin breaks down cross linked fibrin into fibrin products
plasmin produced by tissue plasminogen activator

Question 11

give 4 examples of how types bleeding disorders

Answer 11

congenital - single gene
acquired - multiple
platelet/vessel wall defect
coagulation defect

Question 12

what do platelet /vessel wall defects lead to as well as coagulation defects

Answer 12

p/v - mucosal and skin bleeding (gums)

c - deep muscular bleeds

Question 13

what investigations can be done for bleeding disorders

Answer 13

FBC
coagulation screen
clauss fibrinogen
vWF profile

Question 14

how do you measure the intrinsic vs extrinsic pathway

Answer 14

in - APTT - activated partial thrombplastin time

ex - PT - prothrombin time

Question 15

what do platelet/vessel wall defects leeds to

Answer 15

all give rise to prolonged bleeding time
scurvy (lack vit C)
vWD

Question 16

what are the disease differences between vascular/platelt defects compared to coagulation defects

Answer 16

v/p - superficial bruises, spontaneous, bleeding from skin, immediate and prolonged bleeding

c - deep spreading haemotoma, haemarthrosis, bleeding prolonged

Question 17

what are the three types of vWD

Answer 17

1 - reduced production of normal molecule - lack of vWF

2 - normal count of abnormal molecule

3 - absence of molecule - severe

Question 18

what is the most common bleeding disorder

Answer 18

type 1 vWD

Question 19

what i the inheritance pattern of the types of vWD

Answer 19

normal = AD inheritance

type 3 = AR

Question 20

where is vWF stored and released

Answer 20

endothelial cells - secreted into plasma

Question 21

what is the role of vWF

Answer 21

acts as a glue for platelet aggregation to vessel walls

and as a carrier for VIII

Question 22

what is the presentation of vWD

Answer 22

defective primary homeostasis, skin and mucosal bleeding

Question 23

what is the treatment of vWD

Answer 23

antifibrinolytics - tranexamic acid

DDAVP (desmopressin) - promotes release of vWF from storage granules

factor concentrates containing vWD

Question 24

what is haemophilia and types

Answer 24

x linked recessive - most common clotting factor deficiencies
a - factor VIII deficiency
b - factor IX deficiency

Question 25

what disease would you get bleeding into joint and what is the terminology

Answer 25

haemophilia 
haemarthrosis (joint bleeding)

Question 26

what is the treatment of haemophilia

Answer 26

severe - replacement of missing clotting protein

mild to moderate - DDAVP (desmopressin) (doesn’t work for HB)

Question 27

what are some complications of the treatment of haemophilia

Answer 27

transfusion transmitted infections
inhibitor development - factor doesn’t work
immune tolerance