Haematopoietic Disorders
- Combined incidence is 1 in 10 000 male births
Haemophilia A (Classic haemophilia)
- Deficiency of factor VIII
- Most common of severe disorders
- X-linked recessive inheritance
- Only affects males. Carried by females. 30% are new mutations (very high cf. Other inherited diseases)
- Severity varies depending on level of clotting factor VIII:
- 50% - normal
- 25-50% - seldom have problems
- 5-25 % - severe bleeding with operations (mild)
- 1-5 % - severe bleeding after minor injury (moderate)
- <1% - spontaneous bleeding (severe)
- 50% of known haemophiliacs are moderate or severe
- 5% of patients develop antibodies to factor VIII
- Very difficult to treat. Infused factors are destroyed
Christmas disease
- Deficiency of factor IX
- Less common
- Also X-linked recessive inheritance
- Similar spectrum of severity
Deficiency of factor IX
Less common
Also X-linked recessive inheritance
Similar spectrum of severity
Von Willebrand's disease
- Deficiency of von Willebrand factor
- Autosomal dominant inheritance
Deficiency of von Willebrand factor
Autosomal dominant inheritance
Clinical Presentation
- Male with positive family history
- May present after circumcision; Otherwise first bruising appears at 3-4 months; Severe bruising at walking age; May be spontaneous haemarthroses; Milder forms may present after dental extraction or operative procedure
- Bleeding In the form of:
- Bruises
- Muscle haematomas
- Haemarthroses
- May occur some time after injury
- Defect is in clot formation (2nd phase) rather than haemostasis (1st phase) (See Coagulation)
- May be no known trauma
HIV
- 70% of haemophiliacs who have received pooled untreated factor VIIII preparations are HIV positive
- 90% of severe haemophiliacs are HIV positive
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Lower Limb
