Haemophilia is a X-linked recessive disorder of coagulation. Up to 30% of patients have no family history of the condition.

Types:

• Haemophilia A is due to a deficiency of factor VIII
• Haemophilia B (Christmas disease) there is a lack of factor IX
  • 6x less common than haemophilia A

Epidemiology

• Haemophilia A - 1 in 5,000 of the male population
• Haemophilia B - 1 in 30,000 males

PC

Clinical features depend on the level of factor VIII/IX

• haemoarthroses
• haematomas
• prolonged bleeding after surgery or trauma

Investigations

Blood tests:

• prolonged APTT bleeding time
• prothrombin time normal
• Bleeding time is normal