Haemophilia is an inherited condition that affects the blood’s ability to clot (called coagulation). It is caused by a genetic mutation that may have occurred spontaneously in earlier generations. People living with the condition have fewer clotting factors in their blood than usual, and therefore can bleed more frequently and for longer periods than those without the condition. They also bruise more easily than normal.
Haemophilia usually only occurs in males, although there is a small chance of a girl being born with haemophilia if both parents carry the haemophilia gene. The haemophilia gene is, however, usually carried by women, and although they don’t develop the condition themselves, they may also suffer from some bleeding problems such as abnormally heavy periods. Symptoms can range from mild to severe, depending on the level of clotting factors in the individual’s blood.
In mild cases, symptoms may only present after something like an injury, a dental procedure or surgery. In moderate cases, there may also be frequent bruising and bleeding around the joints from early childhood, and this can cause both severe pain and deformation of the joints. In severe cases, bleeding around the joints and bruising occur more frequently, and spontaneous internal bleeding can also occur. There is also a small risk of bleeding inside the skull, which is known as intracranial haemorrhage, although this usually only occurs if there has been some kind of head injury.
There are two types of haemophilia, Haemophilia A and Haemophilia B, which are caused by mutations with different clotting factors. Haemophilia A is the more common of the two. There is also a rarer form of the condition called acquired haemophilia, which can develop in both men and women as they age. This is thought to be linked to a malfunction of the immune system.
There is no cure for haemophilia, but with appropriate treatment people living with the condition can usually have a good quality of life. Treatment involves injecting clotting factors in order to prevent or treat prolonged bleeding. Without treatment, severe haemophilia can be fatal.
Donors can give either whole blood or specific blood components only. The process of donating specific blood components – red cells, plasma or platelets – is called apheresis.