The disease is hereditary and yet it strikes most patients by surprise – we are talking about “hemophilia“, popularly known as “hemophilia”. Due to a genetic defect, those affected lack a substance that causes the blood to clot. But blood clotting is important because it is the reason why wounds close again. Find out how hemophilia develops and what you can do about it here.
Hemophilia A and hemophilia B
There are two different forms of hemophilia:
- About 80 percent of those affected suffer from hemophilia A. In this variant, there is a lack or deficiency of blood clotting factor VIII, which is a certain protein in the blood.
- In another form, hemophilia B, factor IX is affected.
However, the symptoms are the same in both.
Symptoms of hemophilia
Characteristic of hemophilia is that the blood clots much slower than in other people. As a result, wounds do not heal because hemostasis takes too long or does not work at all. Even minor injuries can lead to extensive bleeding in the tissues and joints. Affected people, known as hemophiliacs, have more frequent bruising and the risk of internal bleeding, for example as a result of bruising or falls, is also increased. The severity of the chronic condition depends on the so-called residual activity of the clotting factors. They are divided into four degrees of severity, with a performance of between 0 and 50 percent. In the worst case, uncontrollable bleeding occurs, which can become life-threatening for the affected person.
Bleeding with severe consequences
Hemophilia sufferers can experience bleeding in any tissue that is heavily infused with veins. Even minor shocks cause hematomas (bruises) in weight-bearing joints such as the knee, elbow, ankle, ankle, and hip. Such joint bleeding can cause severe pain and result in swelling and inflammation. Young children between the ages of one and two are particularly at risk because they often fall or bump themselves in their first urge to move. The injuries not only cause severe pain, but can result in deformed joints and disabilities if not treated properly. Spontaneous bleeding is also a constant risk. They sometimes occur without direct cause, for example in the gastrointestinal tract and brain, or are triggered by surgical procedures, for example when a tooth is pulled.
Inheritance of hemophilia
Hemophilia is a hereditary disease that mainly affects men. This is because the genes for the clotting factor are located on the X chromosome, of which men have only one, but women have a second. The lack of blood clotting factors in women is therefore usually compensated for by their second X chromosome. However, this does not eliminate the danger for their sons. The mother remains the carrier (conductor). Around half of male descendants inherit the disease via their mother. In rare cases, the inheritance can also lead to hemophilia in women: If the father is a hemophiliac and the mother is a conductor, the defective X chromosome triggers hemophilia even in the common daughter.
Acquired hemophilia
Less common, but particularly dangerous, is acquired hemophilia. About 1.5 cases in one million nonhemophiliacs spontaneously develop antibodies against the body’s own clotting factors and thus develop inhibitory hemophilia. Experts therefore assume that this affects about 150 patients per year in Germany. However, it should be noted that the number of unreported cases is very high. The disease occurs mainly in pregnant women and people over 50 years of age who suffer from an autoimmune disease or cancer. In many cases, this form is not even recognized in the first place – and this has serious, sometimes fatal consequences for those affected.
Frequency of hemophilia
Overall, the World Federation of Hemophilia (WHF) estimates that there are 400,000 hemophiliacs worldwide, and about 8,000 in Germany alone. And only just under 30 percent of hemophiliacs are actually diagnosed with this disease. Particularly in those with a mild bleeding tendency, the disease is often barely noticeable in everyday life and is only noticed when bleeding after an operation lasts longer than usual.
Treatment: replacing the clotting factor
Therapy for hemophilia usually involves replacing the missing or defective factor VIII or IX.Corresponding preparations are usually injected intravenously.
- Since the risk of injury is greater in children, they usually receive preventive treatment up to three times a week.
- Adult hemophiliacs administer the missing clotting factor as needed.
In this regard, those affected benefit greatly from medical progress. Today, they are treated earlier and more individually than in the past and can choose between different substances.
Therapy with different substances
So-called plasma preparations are obtained from human blood. In addition, it is now possible to produce factor VIII by genetic engineering. While some hemophiliacs have been infected with HIV and hepatitis via plasmatic products in the past, genetically engineered recombinant preparations are virus-free. In addition, since 2018, it has been possible to inject the antibody emicizumab subcutaneously, i.e. into the subcutaneous fatty tissue of the abdomen or thigh, as a substitute for clotting factor VIII. The intervals between injections can be up to four weeks for preventive use.
Living with hemophilia
Thanks to modern therapy options, hemophiliacs manage to lead relatively normal lives with it – with minor restrictions, of course: Dangerous sports with a high risk of injury and extreme physical stress remain taboo for people with hemophilia.
