Haemophilia – Causes & Symptoms

What is haemophilia?
Haemophilia is an inherited disease that is characterized by abnormal bleeding. It is caused by a poor blood clotting response due to a deficiency of a clotting coagulation factor in the blood.

There are a number of coagulation factors in the blood, mostly proteins that are converted from inactive to active forms whenever the wall of a blood vessel is damaged.

Anyone who suffers from haemophilia is deficient in a factor, most commonly Factor VIII Haemophilia A, and is vulnerable to internal or external bleeding.

Symptoms often begin in infancy and continue through life. Their severity varies among individuals and milder forms of haemophilia may not be apparent until adulthood.

What causes haemophilia?
Haemophilia A is a genetic, or inherited, condition. It is an x-linked genetic defect, sometimes called sex-linked because it is passed on from a mother to her son. In almost every case, there will be a history of the disease within the family.

All of our inborn characteristics – our colour of hair, eyes and so on – are controlled by the action of one or more pairs of genes. Half of each pair comes from one parent, and the other half from the other parent. Every human being has vast numbers of these genes, which are contained in structures called chromosomes, and in each of us a few of the genes are faulty. This is what occasionally causes problems.

Most women have two x chromosomes, while men have one x and one y. In the most common from of x-linked inheritance, the female sex chromosomes of a mother who is unaffected carry one faulty and one normal gene. Her sons therefore have a 50/50 risk of inheriting her faulty gene and thereby inheriting the disorder themselves.

Each of her daughters has an equal chance of being a carrier like the mother – usually unaffected by the disease, but capable of transmitting it to her sons. x-linked disorders cannot be passed down from male to male, so a father who has haemophilia cannot pass it on to his sons.

This is the mechanism by which haemophilia is transmitted from one generation to the next. However, haemophilia will sometimes also appear spontaneously without any known family history of one disease.

How is haemophilia diagnosed and treated?
Apart from the clinical symptoms, laboratory blood analysis for Factor VIII remains the mainstay of haemophilia diagnosis. Treatment almost always involves the transfusion of concentrates of blood products which contain this coagulation factor. Extra transfusions generally have to be given if either surgery or dental care is needed.

What can I do myself?
Haemophilia sufferers must protect themselves adequately before engaging in sports, since a minor fall or blow could result in a severe bleeding episode. Contact sports are best avoided and can be replaced with lower risk, non-contact activities including walking, golf and swimming. Aspirin impairs the formation of blood clots, so it should not be taken.

When should I see my doctor?
Any episode of abnormal bleeding calls for medical consultation. People with severe haemophilia often have to seek emergency treatment over a minor cut or scrape, and some carry emergency supplies of Factor VIII to inject into themselves if necessary.

What will the doctor do?
Laboratory tests on a sample of blood will determine if coagulation is normal and will test the level of Factor VIII. Other tests may be done to see if another clotting problem is causing the symptoms. During a bleeding episode Factor VIII will usually be administered. Although frequent transfusions may also be needed, blood products are now treated to prevent the possibility of the transmission of hepatitis or AIDS viruses.

Is haemophilia dangerous?
Severe haemophilia can be life-threatening if not treated promptly. Even mild haemophilia can cause joint damage and disability if untreated.

Haemophilia can also lead to psychological problems. The parents of a child with haemophilia may become overly protective, making the child feel different from other children. In recent years, some people with haemophilia have suffered the effects of AIDS. Before blood tests for AIDS antibodies were developed, many haemophilia patients received blood products contaminated with the AIDS virus.

Symptoms of Haemophilia
*Serious bleeding or haemorrhaging from a trivial injury.
*Blood-filled swellings inside the skin.
*Blood in the urine.
*Bleeding into the joints, causing a painful arthritis.

What can I do to avoid haemophilia?
As it is an inherited condition you cannot avoid haemophilia, but you can avoid passing it on to your children. Men do not pass the disease on to their sons, but women – who do not appear to have haemophilia – can transmit it to their male offspring.

A simple blood test will identify those who are carriers of haemophilia. If any males in your family have had this condition and you are planning to have children, you may want to consider having this test. You may also wish to see a genetic counsellor for further information, so ask your GP to refer you.

This article is filed under Blood Disorders.