11. Hemophilia A and B

Question 1

what occurs due to chronic hemarthroses in hemophilias?

Answer 1

synovial thickening and synovitis in response to intra-articular blood (knees and ankles most commonly)

Question 2

diagnosis of hemophilias

Answer 2

↑ PTT (corrected by mixing studies)

PT and PLT count is normal

Question 2

diagnosis of hemophilias

Answer 2

↑ PTT (corrected by mixing studies)

PT and PLT count is normal

Question 3

management of hemophilias

Answer 3

1. factor replacement therapy
2. desmopressin (hemophilia A)
3. Anti-fibrinolytic therapy (tranexamic acid)
4. Emicizumab (hemophilia A)

Question 4

complications of hemophilia

Answer 4

1. inhibitor formation- antibodies against F. VIII or F.IX (annual screening)
2. infectious diseases (HIV and hepatitis)- not common anymore

Question 5

what is seen in a mixing test of a patient with hemophilia in the presence of a factor inhibitor?

Answer 5

the PTT on a 1:1 mix is abnormally prolonged

the inhibitor neutralizes the F. VIII clotting activity of the normal plasma

Question 6

how to eradicate an inhibitory antibody of hemophilia?

Answer 6

immune tolerance induction (ITI)
daily infusion of missing protein until the inhibitor disappears

require periods longer than 1 year