haemostasis and inherited blood disorders

Question 1

what do glycoprotein molecules have receptors for?

Answer 1

agonists, adhesive proteins, coagulation factors, other platelets

Question 2

what are the most abundant receptors on the platelet cell membrane?

Answer 2

Gp2b/3a heterodimer complex, Gp1b

Question 3

what what platelet specific granules are in a platelet?

Answer 3

o Dense osmophilic granules; dense bodies, alpha granules
o Nucleotides; ADP
o Alpha granules

Question 4

what do alpha granules contain?

Answer 4

VWF, platelet factor 4, b-thromboglobulin, thrombospondin, factor V, fibrinogen, fibronectin, platelet derived growth factor, high molecular weight kininogen, tissue plasminogen activator inhibitor-1

Question 5

what is Bernard Soulier syndrome?

Answer 5

Lack of Gp2b

Question 6

what is Glanzmann’s syndrome?

Answer 6

lack of Gp2b/3a

Question 7

how are serious inherited platelet disorders treated?

Answer 7

Likely to need platelets or Novoseven

Question 8

name less serious platelet disorders

Answer 8

o Storage pool disorders

o Weak agonist response defects

Question 9

what is the inheritance pattern of von willebrand disease?

Answer 9

autosomal inheritance

Question 10

what is type 1 VWD?

Answer 10

mild to moderate deficiency; VWF is working but there isn’t enough of it

Question 11

what is type 2 VWD?

Answer 11

protein is present but isn’t working

Question 12

what is type 3 VWD?

Answer 12

totally absent protein

Question 13

how do you treat VWD?

Answer 13

DDAVP, tranexamic acid, VWF containing concentrate

Question 14

how does DDAVP work?

Answer 14

stimulates a person to release more VWF that’s already stored in platelets

Question 15

what treatment is given is someone with VWD experiences prophylaxis at home?

Answer 15

they can be taught to treat themselves intravenously

Question 16

where is tissue factor found?

Answer 16

Present on subendothelial tissue – expressed by cells which are normally not exposed to flowing blood

Question 17

what does APTT test?

Answer 17

the intrinsic pathway

Question 18

what does PT test?

Answer 18

the extrinsic pathway

Question 19

what does thrombin time test?

Answer 19

the common pathway

Question 20

in severe haemophilia, where do you experience bleeding?

Answer 20

soft tissue, joints (knees, ankles, elbows), psoas, intracranial, operative sites (haematomas may become compromising)

Question 21

what is antithrombin?

Answer 21

• Major inhibitor of thrombin and Xa - also inhibits VII, IX, XI
• Member of the SERine Protease INhibitor family

Question 22

how does heparin affect antithrombin?

Answer 22

Inhibitory activity increased 5 -10,000 fold in the presence of heparin