Haemophilia A is an inherited bleeding disorder caused by deficiency or dysfunction of clotting factor VIII.
It is usually an X-linked recessive disorder and therefore predominantly affects males.
It causes prolonged bleeding because blood does not clot normally.
Common manifestations include:
Prolonged bleeding after injury or surgery
Spontaneous bleeding
Bleeding into joints and muscles
Severity depends largely on the level of factor VIII.
Treatment may involve factor VIII replacement therapy and, in selected cases, other therapies such as emicizumab.
Key Pointers
Factor deficient: VIII
Inheritance: X-linked recessive
More commonly affected: Males
Major complication: Recurrent joint bleeding
Different from Haemophilia B: Factor IX deficiency in Haemophilia B
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