If you have a technical query about a Shire product, please call medical information on +44 (0) 1635 798777
To report an adverse event please contact Pharmacovigilance
on +44 (0) 203 655 2430 or by email at firstname.lastname@example.org
This website is intended for carers and patients living with haemophilia.
What is acquired haemophilia?
Many people have heard of haemophilia but usually as an inherited blood disorder that affects boys and men from birth. This is called congenital haemophilia.
Acquired haemophilia shares some similarities with congenital haemophilia but is a distinctly different condition.
Normally, blood clots after injury or surgical procedures by a complicated process involving a number of different proteins. These are mostly made in the liver and then released into the blood.
In acquired haemophilia, the person may not have a history of bleeding. At some point in their life their immune system develops an antibody to their own factor VIII - this antibody stops FVIII working normally and removes it from the circulation. This lack of factor VIII activity is why these patients bleed; sometimes this bleeding is in response to trauma, and sometimes patients will bleed for no apparent reason.
What causes it?
In about half the cases of acquired haemophilia that are diagnosed, the cause is never established. Part of the immune system becomes over-active towards Factor VIII.
The immune system (which consists of some of the blood cells, the lymph glands and the spleen) exists to protect the body from attack by bacteria, viruses and other proteins that it regards as foreign. It does this by making proteins known as antibodies to destroy the foreign “invaders”.
In acquired haemophilia, the immune system suddenly starts to regard the body’s own Factor VIII as a foreign protein and consequently makes an antibody to destroy it. This antibody is also known as an inhibitor because it inhibits the action of Factor VIII.
In some people, it may be associated with another illness. Examples include rheumatoid arthritis, ulcerative colitis, asthma, psoriasis and cancer. If this applies to you, your doctor will discuss this with you individually.
How common is it?
Acquired haemophilia is a very rare condition, thought to affect only about one person for every million of the population. For this reason most people (including some doctors) have no experience of it and management of the condition is usually carried out by a specialist Haemophilia Centre in a hospital.
How is it diagnosed?
In most cases, the first sign is extensive bruising on the body, usually on the limbs or trunk, that is out of proportion to knocks or injuries received. The bruises may be very large, often extending the whole length of an arm or leg. Although they look alarming they fade with time.
Sometimes, bleeding can occur into muscles, which can be painful and cause temporary loss of movement of that part of the body.
Occasionally, acquired haemophilia may show as prolonged bleeding after a surgical procedure or as blood in the urine or from the bowels.
Is it serious?
Acquired haemophilia can be very serious, although once it is diagnosed a number of treatments are available which are often highly successful.
How is acquired haemophilia treated?
Healthcare teams who treat patients with acquired haemophilia are trying to do two things at the same time –
• control or stop the immediate bleeding
• get rid of the antibody that is causing the condition
Bleeding is controlled by injecting blood clotting factors directly into the patient’s veins – most commonly these are combinations of clotting factors that help blood to clot without the need for factor VIII.
As soon as the diagnosis of acquired haemophilia is confirmed other drugs will be given to stop the body producing the antibody that causes the condition – this process is called immune suppression. These drugs will be prescribed for several months, and regular blood tests will be needed to check that the level of antibody in the blood is going down. If this stops going down, or starts going up again, then different combinations of drugs will be used.