The normal lifespan of a red blood cell is 120 days, but in thalassaemics this is shortened. The abnormal production of beta chains means that alpha chains do not have partner chains to pair with in order to make haemoglobin. Excess free globin chains precipitate and damage the red blood cell membrane. The cells eventually lyse, few red blood cells, and little amount of haemoglobin in them induces anaemia. To maintain red cell viability and function, thalassaemics are given blood transfusions. The transfusion of red cells corrects anaemia and makes sure the tissues get a normal amount of oxygen so that the body can grow and function normally.
Transport of oxygen from the lungs to the tissues is carried out by a highly specialised molecule, haemoglobin, which is contained within red blood cells. Haemoglobin (Hb) consists of two pairs of globin chains.
2 alpha + 2 beta = Hb A
2 alpha + 2 gamma = Hb A2
2 alpha + 2 delta = Hb F
In healthy adults approximately 95% of the Hb is Hb A, <3.5% is Hb A2 and <1% is Hb F.
The precise structure of globin chains is encoded by the respective genes. There are two forms ‘alleles’ of every kind of gene in the body, one inherited from your mother and one from your father. Normal people have two normal genes for haemoglobin synthesis. Sometimes an individual may inherit a defected gene from one parent but a normal one from the other (heterozygote), they are carriers of the trait, however the activity of the normal gene makes enough stable haemoglobin.
Yes. The way to prevent thalassaemia is to prevent the birth of an affected child. Prenatal diagnosis, the ability to detect abnormalities in an unborn child, has been used for over three decades.
The Thalassaemia is a blood disorder. Blood is a part of your body.
Blood is made up of light yellow liquid, called plasma, and of three types of “cells” which float round freely in the plasma. There are 3 types of blood cells, red cells, white cells and platelets.
You have many more red blood cells than white blood cells. The red blood cells are full of hemoglobin, which is red, and this is what makes your blood look red. Hemoglobin picks up oxygen form the air in your lungs, and carries it round to your tissues, where it lets it go. To live, your tissues need to breath, so they need oxygen.
New red blood cells are being made all the time in your bone marrow. They only live about 120 days. Then they are destroyed in your spleen.
If you have too few red blood cells, or there is too little haemoglobin in them, you have “anaemia”. This simply means a shortage of blood. If the anaemia is mild, it does no harm and you may not even notice it: but if it is severe, you are ill, because your tissues do not have enough oxygen.
The commonest form of anaemia is “iron deficiency anaemia”. This can happen if you do not have enough iron in your diet. It can be cured by taking iron medicine. Thalassaemia is quite different form iron deficiency anaemia. It is an inherited anaemia. It can not be cured by taking any medicines.
By measuring the amount of haemoglobin in your blood. Haemoglobin is written Hb, for short. The usual Hb level for men is about 13-16 g/dl, for women and children it is about 11-14 g/dl.
Moderate anaemia means an Hb level of about 8-11 g/dl.
Severe anaemia means an Hb level of less then 8 g/dl.
Thalassaemia is an inherited disease of the blood. It reduces the amount of haemoglobin your body can make, so it can cause anaemia.
Every characteristic of your body is controlled by “genes”, Genes are parent in every cell of your body. You have two of every kind of gene, one passed on form your mother, the other passed on form your father. You have two genes that control how haemoglobin is made on each of your red blood cells.
“Normal” people have two normal genes for haemoglobin. Healthy carriers of B –thalassaemia trait have one normal gene for haemoglobin and one altered one: they are halthy because one gene is working well. Since one gente is ingerited trom each parent, al least one of their parents must be a carrier.
People with B-thalassaemia major have two altered genes for haemoglobin, one inherited from each parent, so both their parents must be carriers.
Now let us consider three sorts of married couples:
- Both parents are “normal”.
They cannot possibly pass on thalassaemia trait or thalassaemia major of their children.
- One parent has thalassaemia trait and one is “ normal”
All the children must inherit a normal gene form the “normal” parent. However, they may inherit a normal or a thalassaemia gene from the carrier parent. For each child there is a one in two (50%) chance of inheriting the thalassaemia gene from the carrier parent: it this happens the child will be completely normal. None of this couple’s children can have thalassaemia major.
- Both the parents are B-thalassaemia carriers: i.e. they are a “couple at risk.”
This is why couples of carriers have a one in four( 25%) chance in each pregnancy of having a child with thalassaemia major; a one in two (50%) chance of having a child with thalassaemia trait; and a one in four (25%) chance that the child will inherit a normal gene from both parents, and so will be completely normal.
It is possible to test the foetus during pregnancy, to see if it has thalassaemia major. Then the parents can decide whether or not to keep the pregnancy. This is called parental diagnosis. To do this test, it is necessary to study blood from both parents, to find out exactly which type of thalassaemia gene they carry.
Usually thalassaemia is severe, and people who have it need regular blood transfusions in order live. This is called thalassaemia major. In some cases the disease in milder, or even very mild, and the person can live quite well without blood transfusions. This is called thalassaemia intermedia.
Other names for thalassaemia major are
- Cooley’s anaemis
- B-thalassaenlia major
- Homozygous B-thalassaemia
- Homozygous thalassaemia
- Mediterranean anaemia
During pregnancy, thalassaemia major does not affect the foetus. This is because the toetus has a special sort of haemoglobin, called “foetal haemoglobin” (Hbf for short). Children and adults have a different haemoglobin called “adult haemoglobin” (HbA for short). When a baby is born, most of its haemoglobin is still the foetal kind, but during the first 6 months of life it is gradually replaced with adult haemoglobin. The problem with thalassaemia, is that the child cannot make enough adult haemoglobin. Therefore children with thalassaemia major are well at birth, but usually become it before they are 2 years old. They usually become quite anaemic (their haemoblobin level is usually less than 55% (8 g/dl). So they become pale, do not grow as well as they should, and often have a big spleen. The number of months that can pass before a thalassaemic child becomes ill can differ quite a lot from case to case. This is because thalassaemia can be caused by several different defects in the haemoglobin genes. However, nearly all children with severe B-thalassaemia become ill by 4 years of age, and need blood transfusions.
The anaemia gets worse, the child stops growing altogether, and the spleen goes on getting bigger, so the stomach gets very big. The bone marrow, the tissue that forms the red blood cells, expands inside the bones because of this. But its efforts to make more and more red blood cells are useless. The red cells it makes do not contain enough haemoglobin, and most simply die without ever getting out of the bone marrow. However, the marrow’s efforts to expand make the bones weak and alter their shape. The cheekbones and bones of the forehead begin to bulge and the child’s face gets a characteristic look, so that people can see from a distance that something is wrong. The spleen’s normal job is to destroy old red blood cells in the circulation, but as time passes it begins to destroy young red blood cells as well. Finally it also kills white blood cells and platelets. This is called “hypersplensim.” So in the end, the spleen makes the child’s illness worse.
Two different treatments are now possible, traditional treatment, and bone-marrow transplantation
Traditional treatment this consist of (1) blood transfusion, (2) removing the spleen (splenectomy), and (3) desferal treatment.
- Blood transfusion
Thalassaemics are only short of red blood cells: they make other parts of the blood quite normally, so they need transfusion of red blood cells. If you keep the Hb 6-10 g/dl it is called low transfusion scheme live long enough to grow up. The “high transfusion scheme” recommended here avoids most of these problems. It has been used for many years in Western countries. There are three reasons for high transfusion.
- It corrects your anaemia, and makes sure that your tissues get a normal amount of oxygen. This allows you face looks normal.
- It lets your bone marrow rest, so that your bones can develop normally and will be strong, and your face looks normal.
- It slows down, or prevents, any increase in the size of your spleen, so it prevents hypersplensim.
When the spleen becomes too active and starts to destroy red blood cells, transfusions become less and less effective. Then it may become necessary for a surgeon to take spleen out. This operation is called splenectomy.
- Desferal treatment
Every 400ml of blood transfused contains about 200 milligrams of iron. Packed red cells have 200 mg of iron per 200-250 ml of blood. This iron can not be taken out of the blood because it is part of the haemoglobin, which your body needs. On its own, your body can only get rid of a tiny amount of iron, so if you have transfusions regularly, iron gradually accumulates in your body. It is stored in certain organs, especially the liver, the heart, and the “endocrine” glands. Your body can store a lot of iron safely, but in the end it can damage the organs where it is stored. Fortunately, there are drugs that can pick up the iron, and carry it out of your body in your urine and faces. The only one that is used regularly at present is desferrioxamine, which is also called “desferal.” If you sue Desferal regularly, you can keep the amount of iron in your body down to a safe level.
For a well-treated patient thalassaemia is quite different from the untreated disease. There is no anaemia, growth is normal, and the face and the bones look normal. Remember that thalassaemia will be life-long. With modern treatment there is real hope for thalassaemics of leading a long and useful life.
One should try not to let treatment interrupt schooling or work. We are certain that, as time passes, the quality of life will steadily improve.
In general, no, but we do recommend avoiding animal foods that are rich in iron, such as liver and spleen.
Yes, avoid any with added iron also avoid extra Vitamin D.
The answer is the same as for non-thalassaemics- it depends on whether or not you have any heart problems, as a general rule, most thalassaemics can take part in most sports, up to their own capacity.
It might be wise for thalassaemics to avoid altitudes above 3,500 meter, or to make sure they have a transfusion immediately before going to high mountains. Otherwise, there are no restrictions.