
What is hemophilia?
Hemophilia
Hemophilia
A clotting disorder that occurs mostly in males. The disorder makes bleeding hard
to control.
is a
bleeding
Bleeding
In hemophilia, a collection of blood in an area, such as a muscle or joint.
disorder
that prevents blood from clotting
Clotting
The process of forming into a clot or clots.
properly.
There are 13 proteins in blood called clotting (coagulation) factors
Clotting (coagulation) factors
Substances in the blood that work together with platelets to form a fibrin clot
in an injured blood vessel and stop bleeding. Clotting factors are named using Roman
numerals (Factor I [1] to Factor XIII [13]).
that work
together in a series of steps to form blood clots
Clot
The thickened mass of blood and cells your body forms to stop the bleeding at the
place where you have been injured.
. People
with hemophilia are missing one of these clotting factors, so they may need special
treatment to make their blood clot.
What are inhibitors?
Inhibitors
Inhibitor
A substance made by the body that attacks factor so it cannot work as well. For
example, a Factor VIII (8) inhibitor would keep Factor VIII from working with other
factors and platelets to stop bleeding.
are a complication
of hemophilia. People with severe hemophilia A
Hemophilia A
A bleeding disorder caused by lack of Factor VIII (8). It is sometimes called classic
or standard hemophilia.
or
B
Hemophilia B
A bleeding disorder caused by lack of Factor IX (9).
are
usually treated by replacing the missing
factor VIII (8)
Factor VIII (8)
One of the 13 clotting-factor proteins that helps form blood clots.
or
factor IX (9)
Factor IX (9)
One of the 13 clotting-factor proteins that helps form blood clots.
through
infusion
Infusion
The injection of medicine directly into a vein using a needle and syringe.
. For some
people, however, this treatment does not work. Their bodies react as though the
treatment is an invader and their immune system
Immune system
A mechanism within the body used to protect itself from harmful substances.
develops
antibodies
Antibodies
Cells of the immune system that fight and destroy viruses and bacteria that can
cause infection.
—inhibitors—that
attack and
neutralize
Neutralize
To counteract the effect of something so that it is not capable of producing change.
the factor
VIII or IX. The neutralized factor
Factor
A protein in the blood that helps form blood clots.
is not able
to stop the bleeding.


