Hemophelia A (classic hemophelia)

Question 1

Definition

Answer 1

• Sex-linked recessive coagulation defect due to deficiency of factor VIII-C
• 20% of cases are new mutations.
• Hemophilia A represents 80% of all hemophiliacs

Question 2

Pathophysiology

Answer 2

• Factor VIII-C is synthesized by the liver and reticuloendothelial system
• In plasma, factor VIII-C is stabilized and protected from degradation by Von Willebrand factor(vWF) protein
• In the presence of normal vWF, the half-life of factor VIII-C is approximately 12 hours, whereas in the absence of vWF, the half-life of factor VIII-C is reduced to 2 hours

Question 3

Pattern of deficiency

Answer 3

• Hemostatic level of F VIII-C is >30- 40U/L (30-40%); below which bleeding occur
• Plasma level of Factor VIII-C in carrier females is between 30-50 %

Question 4

Clinical picture

Answer 4

Severe disease→F8 <1% → bleed spontaneously
-moderate → F8 1-5% → Bleed with minor

trauma
Mild disease → 5-25% → Bleed with severe

trauma

Question 5

Con the clinical picture

Answer 5

1. In neonate Unusual bleeding from the circumcision site or umbilical stump
2. External bleeding e.g.
   Epistaxis
   • Dental /mouth bleeding
   • GIT bleeding Hematuria
3. Skin bleeding
   • Easy bruising
   • Ecchymotic patches Hematomas
   • No petechaie
4. Hemarthrosis🌚 target joint
   • The hallmark of hemophilia A and B
   • Affects mainly the big joints of the lower limbs
   • Affected joint become swollen, red, hot, and tender with limited mobility
   • Tend to be recurrent
   • Recurrent hemarthrosisp joint fibrosis / ankylosis & muscle atrophy
5. Internal bleeding e.g.
   • Muscle hematoma Intracranial Retroperitoneal Hemothorax
   -

Question 6

Inv for both

Answer 6

 PTT is prolonged 2-3 times above the normal range, whereas other

screening tests are usually normal (including PT).

 Mixing study is positive.

 Specific F8 or F9 assay is used to confirm the Dx.

 Hemophilia carriers (e.g. other family members) can be screened by

Genetic studies or F8:VWF ratio.

Question 7

Tx

Answer 7

Nelson

Question 8

Tranexamic acid

Answer 8

Antifibrinolytics
- 1g loading in 10 min the 1g maintenance in 8 h
For truma in first 3 h

Question 9

Complications of hemophilia

Answer 9

A. Due to bleeding

• Hemophilic arthropathypjoint stiffness & Muscle atrophy
• Severe intracranial hemorrhage.
• Severe blood lossp hypovolemic shock

B. Complications of transfusion (See chronic transfusion in thalassemia )

C. Complications of factor VIII therapy

1. Hypersensitivity reactions
2. Factor VIII inhibitors (Antibodies)

• Develop in about 5-10 %
• Hemorrhage become refractory to treatment
• Inhibitors (measured by Bethesda Units) should be screened for annually

Question 10

Hemophelia B (Christmas disease)

Answer 10

• Factor IX deficiency.
• Incidence: 1 / 50.000(in contrast to hemophelia A which is 1 / 10.000)
• Sex-linked recessive disorder.
• As hemophelia A but milder.
• Treated by: Recombinant factor IX or factor IX concentrate given/24 hours.
• Prophylactic treatment: Recombinant factor IX twice a week.

Question 11

Hemophelia C

Answer 11

• Factor XI deficiency.
• Autosomal recessive disorder so can affect both sexes.
• Very mild disease.
• Treated by fresh frozen plasma given / 48 hours.