Hemophilia Flashcards
inheritance pattern
x-linked recessive
bleeding severity in hemophiliacs correlates to
degree of factor deficiency
To watch for with bleeding in extremities in hemophiliacs
compartment syndrome
Term for joint syndrome stemming from long term hemophilia
Hemophilic arthropathy
Most important principle of management
Treat bleeding ASAP (will not stop)
treatment options
1) *recombinant factor concentrates
2) AntiFibrinolytics
3) Hemlibra
4) DDAVP
Breakthrough drug for hemophilia treatment + mechanism + indication
Emicizumab (factor VIII mimetic)
- prophylaxis
Interpretation of mixing study in which aPTT doesn’t fully correct
- factor inhibitor (with a factor deficiency, aPTT will FULLY correct)
- This indicates acquire hemophilia A
Treatment of acquired hemophilia A
Activated factor VII OR Activated prothrombin complex concentrate OR Recombinant porcine factor VIII
Disease association of acquired hemophilia A
CLL
Risk factors for acquired hemophilia
- Elderly adults
- Women
Clotting factor deficient in hemophilia A
Factor VIII
Clotting factor deficient in hemophilia B
Factor IX
FDA approved recombinant factor IX concentrates
Benefix
Alprolix
Hemlibra (emicizumab) mechanism
- replaces function of factor VIII
Severe hemophilia A definition
Factor level less than 1%
Factor level defining Moderate hemophilia A
Factor level between 1 and 5%
Mild hemophilia A definition
Factor level between 5 and 50%
initial factor dose required to raise factor VIII level to normal for severely deficient
50 units/kg
Goal of factor replacement in a major bleed
Goal is to raise factor levels to 100% initially and then maintain factor levels above 50% by bolus q8-12h or continuous infusion.
Management of mild bleed in patient with mild hemophilia A
Desmopression or Amikar if mucosal bleed
Goal of factor replacement with major surgeries
Give Factor VIII to maintain factor level at 100%;
Taper postoperatively to maintain levels above 50%; do not let it drop below 50%
Assay used to check for factor VIII inhibitor
Bethesda assay
What is FEIBA? mechanism? use?
- activated PCC
- bypasses the Factor VIII/common pathway and provides factor II/prothrombin to form a clot
- used fro patients with factor VIII inhibitors
problem with FEIBA
Can be highly thrombogenic
Prophylaxis for bleeding for patients with an inhibitor or acquired hemophilia
FEIBA (activated prothrombin complex concentrate)
What are the 2 management strategies for hemophiliacs?
On demand (factor replacement during bleeds) vs prophylactic
Management of hemophiliac with hypersensitivity or anaphylaxis to recombinant factor
- can’t give them any of the factor (either plasma derived or recombinant)
What is inhibitor development associated with?
- increased risk of anaphylactic reaction to factor administration
Options for managing an inhibitor
- immune tolerance induction (ITI or desensitization)
- immunosuppressive drugs, including rituxan
Management of hemophilia B patient with inhibitor
recombinant factor VIIa (Novo Seven)
What is REBINYN?
- Pegylated recombinant factor IX
- indicated for on-demand treatment and control of bleeding episodes
MOA of emicizumab
- bridges activated factor IX and factor X to restore the function of activated factor VIII
