Von Willebrand's disease

Question 1

the most common inherited bleeding disorder?

Answer 1

Von Willebrand’s

Question 2

inheritance for Von Willebrand’s

Answer 2

autosomal dominant fashion

Question 3

Role of von Willebrand factor

Answer 3

it is a large glycoprotein
promotes platelet adhesion to damaged endothelium
carrier molecule for factor VIII

Question 4

type of von willebrand disease ?

Answer 4

type 1: partial reduction in vWF (80% of patients)

type 2*: abnormal form of vWF

type 3**: total lack of vWF (autosomal recessive)

Question 5

investigation in von willebrand disease ?

Answer 5

prolonged bleeding time

normal PT -11 to 13.5 seconds.

APTT may be prolonged (21 to 35 seconds)

factor VIII levels may be moderately reduced
(50% to 150% - )

defective platelet aggregation with ristocetin

Question 6

management of von willebrand disease ?

Answer 6

tranexamic acid for mild bleeding

desmopressin (DDAVP): raises levels of vWF by inducing release of vWF from Weibel-Palade bodies in endothelial cells

factor VIII concentrate - factor VIII concentrate should be avoided when possible to minimise the risk of transfusion acquired viral illnesses

Question 7

clinical features of von willebrand ?

Answer 7

epistaxis and menorrhagia are common whilst haemoarthroses and muscle haematomas are rare