This page presents
some basic information about haemophilia.
The term "haemophilia" covers a whole range of blood clotting disorders.
Our blood needs to clot to seal any wound from infection, and to
stop the person from bleeding to death.
There are various
types of haemophilia, mostly involving a lack of one or more "factors"
in the blood that make it clot when a person is cut. A person may
have mild or severe haemophilia, depending on how low the levels
of clotting factors are in their blood.
can you tell if a person has haemophilia?
People with haemophilia don't bleed more than anybody else, but
if they're cut, they can't stop bleeding. They also tend
to bruise more easily, because a bruise is really a form of internal
bleeding, and a person with haemophilia will bleed for longer.
A person needs
a blood test to tell if they have haemophilia, which detects the
clotting factors in their blood. With mild haemophilia, you may
not know about it until you have surgery, dental extractions or
some major injury.
do you get haemophilia?
You cannot catch haemophilia, but you may inherit it from your parents.
Only males can have haemophilia,
but both males and females carry the genetic defect.
Here's how it
genes in our cells are arranged in long chains, called "chromosomes".
We're interested in just two chromosomes: called "X" and "Y" because
of their shape.
The "X" chromosome
carries instructions for the body to produce clotting factors.
If an "X" chromosome has this part damaged, then the instructions
will be missing, and the person may have haemophilia.
we said "may have". This is because females have two "X"
chromosomes, so their other "X" chromosome has the instructions
and thus they can make clotting factors normally.
males have an "X" and a "Y" chromosome. This means that if they
have a damaged "X" chromosome, they have no instructions anywhere
about how to make clotting factors, and thus the person has haemophilia.
father with haemophilia
always pass the gene on to his daughters, but they won't
(they'll get his "X" chromosome, and be a carrier).
sons will not be affected
(they get his "Y" chromosome,
which is normal).
mother who is a carrier
(with a damaged "X" chromosome)
has a 50:50 chance of passing the gene on to her children
- only her sons may have haemophilia.
Her daughters may be carriers.
a condition called "von Willebrand disease" which can
affect both males and females. This is a blood clotting deficiency
along with wound repair problems.
do haemophiliacs deal with bleeding?
The basic treatment when a bleed happens is an injection of the
missing "clotting factor". As people get older, they learn
to give these injections themselves, and unless the bleed is serious
they may not need to go to hospital.
the injection is given, the better, so that permanent damage to
joints and muscles is avoided.
factors" are often stored as dried powder, and mixed with sterile
water when need for an injection. Once mixed, the clotting factors
only last for a few hours, so the person may need several injections
to deal with a major bleed. Of course, most people's bodies make
their own clotting factors all the time.
problems do haemophiliacs have?
Apart from the risk of bleeding too much when injured, a person
with severe haemophilia can bleed internally, which causes problems
when they bleed into a joint. This is because blood is slightly
acid and will attack the joint, leading to arthritis.
into a joint happens, the person may feel an ache or tingle in that
area. Unless it's treated fast, this will develop into stiffness
and swelling, and a great deal of pain.
use clotting factors made from blood donations. Nowadays, the products
are treated to remove any viruses before being used. before this,
there was a risk of diseases such as hepatitis (a nasty liver condition)
or even HIV, possibly leading to AIDS.
There are many haemophiliacs who are infected with
these through no fault of their own.