Dr McLeod Chitiyo
National Blood Service Zimbabwe (NBSZ) will be partnering with the Zimbabwe Haemophilia Association (ZHA) who will be hosting a Corporate Day in the Park in Africa Unity Square on Thursday July 26 2012. The Corporate Day will form part of the awareness and fund-raising efforts of the ZHA. NBSZ has helped the ZHA through the years and, as part of our continued efforts, this week’s article will focus on educating the public about Haemophilia and Blood Transfusion.
The fluid state of the blood
The modern concept is that blood coagulation (clotting) is a dynamic process in which 12 coagulation factors interact and lead to coagulation. They are antagonised by contrary forces, anti-coagulants and fibrinolylic agents (substances that destroy clots). This is normal in life. If a person has a superficial skin injury, some bleeding will take place, but the coagulation factors will soon stop the bleeding by forming a clot. Soon afterwards the anti-coagulants and fibrinolytic agents come into action to remove the blood clot and restore the fluidity of the blood.
However, the clotting factors may be defective in their formation and they fail to function properly, i.e. to stop bleeding following minor injury to the skin, joints or small blood vessels. The most common bleeding disorders due to deficient plasma clotting factors are those due to defects of factors VIII and IX which exhibit many similarities. Both are called Haemophilia, the factor VIII deficiency being called classical Haemophilia while the factor IX deficiency is also known as Christmas Disease.
The incidence of haemophilia and Christmas varies in different countries and it is difficult to assess the exact number in various countries. In Britain it is estimated that haemophilia occurs in about 12 per 100 000 persons. Zimbabwe has haemophiliacs but there is no recent study to determine how many are affected. The diseases are transmitted as a sex-linked recessive characters, affecting males and transmitted by female carriers. True haemophilia may also occur by mutation, no family history being obtained in about 30% of cases.
Factor VIII levels in Haemophiliacs
Several affected haemophiliacs have no detectable Factor VIII activity in their plasma and suffer from repeated episodes of spontaneous bleeding. Patients whose Factor VIII activity is 1-5% of normal are moderately affected and have infrequent attacks of bleeding. Those with levels exceeding 5% are mildly affected and seldom have spontaneous bleeding. In many cases, episodes such as spontaneous bleeding into joints can be satisfactory treated by raising the factor VIII level to 10-20% of normal.
Treatment of patients with haemophilia
Effective treatment for haemophilia has become available in the last four decades or so, and consists of the administration of the deficient clotting factor via intravenous administration. In the first decades, the clotting factors were purified from human plasma. From the 1990s, recombinant (genetically engineered, rDNA) factor VIII or IX has gradually replaced the plasma products. When patients suffer severely from haemophilia, they are treated with prophylactic infusions a couple of times a week at home or with the assistance of a family member. Monitoring of treatment usually takes place in centres of reference. Advisory guidelines have been developed for appropriate treatment. An important factor that has contributed to an effective control strategy of the disease is the existence of patient support groups that are present in most countries collaborating with medical advisors. Most of today's haemophilia societies are organised within the World Federation of
Haemophilia (WFH), founded in 1963.
In the past, treatment of haemophilia has been involved with transmission of viral infections, e.g. HIV. Nowadays, the clotting factors used are protected and treated in such a way that transmission of viruses is not possible. The next important step for curative treatment in the future is gene therapy.
Side-effects of treatment
As mentioned above, severe forms of haemophilia are characterised by major bleeding after minor trauma. These haemorrhages often occur into joints, eventually causing severe joint impairment. This is the most important complication of haemophilia, which can be prevented if treatment is available. In developing countries treatment is most often not available. A second complication of haemophilia, when treatment is available, is the occurrence of neutralising antibodies to factor VIII or IX. Neutralising antibodies in this instance are molecules that bind specifically to factor VIII or IX, thereby inhibiting the effect of treatment.
The third and most tragic complication of treatment of the disease is the transmission of blood-borne viruses by the blood products used for haemophilia, in the past, like HIV, hepatitis B virus (HBV) and hepatitis C virus (HCV).
Plasma-derived products have been safer for HBV and HIV since 1985 and also for HCV since 1992. Bleeding episodes, especially into joints, are very painful and adequate pain control must be given. During acute bleeds, rest is required followed by gradual mobilisation.
The optimal management of haemophilia requires a team approach, with interested haemotologists, physiotherapists and orthopaedic surgeons working together to minimise permanent joint damage.
Haemophilia in developing countries
Only about 30% of patients with haemophilia in the world are diagnosed and receive treatment. The majority of these people live in the more prosperous countries, where comprehensive haemophilia is included in the National Health Care System. One of the main goals of the WFH is to help and encourage haemophilia care in developing countries together with national haemophilia organisations, health care providers and government officials to assess their needs and develop a national plan for haemophilia care.
Improving the possibility of treatment of haemophilia in developing countries also means that there is an opportunity to improve the infrastructure of a National Blood Transfusion system and, as a consequence, the development of some basic plasma-derived blood products. When there is a good screening programme for HBV, HCV and HIV, the use of plasma-derived products for haemophilia can contribute to the treatment of haemophiliacs in the developing world without the need to import the 10-20% more expensive rDNA clotting products. The cost of treating patients with haemophilia has increased substantially over the decades because of the introduction of new methods (e.g. rDNA) and new government regulations asking for viral inactivation safety procedures. A patient with mild haemophilia symptoms costs about €30 000 and a patient with severe symptoms about €125 000 per year.
A safe blood supply
The tragic occurrence of viral transmission (HIV, HCV) in haemophiliacs all over the world in the early 1980s clearly demonstrates the need for a safe blood supply. There has been a long, historical debate about the pros and cons of a blood transfusion system with voluntary, unpaid versus paid blood donors. For all people who need a blood transfusion, the issue of a safe blood supply remains relevant.
The World Health Organisation (WHO) is strongly in favour of voluntary unpaid blood donors because of safety reasons.
Haemophilia bore a heavy brunt of HIV transmission when the virus entered blood supply systems in many countries in the 1980s. Every effort should be made to ensure a safe blood supply in developing countries, such as ours.
- For more details on the ZHA Corporate Day, you can get in touch with the president of the ZHA, Mr Simbarashe Maziveyi, on 0772339796/ firstname.lastname@example.org or Mr Elton Share on 0772402520/ email@example.com
- For your questions and answers, please write or contact, Esther Massundah, Public Affairs Manager, on 707801-4, mobile 0712612829 or email emassundah@bloodbank.
- co.zw firstname.lastname@example.org