Thalassaemia is a common inherited disorder, for which no cure has yet been found. It is estimated that in India there are over 100,000 cases of major thalassaemia and nearly 30 million carriers of the thalassaemia gene. The disease is more prevalent in certain communities like Sindhis, Punjabis, Gujaratis, Bengalis, Gaurs and Saraswats.
What is thalassaemia?
It is a severe genetic blood disorder in which the red cells of the blood are abnormal and die fast leading to anaemia. Due to this the child may require frequent blood transfusions. Gradually the liver and spleen enlarge and the bones of the forehead and face become prominent. After several years, iron gets deposited in various organs, affecting their function and leading to death. Thalassaemia is essentially of two types:
Thalassaemia major - is a serious disease in which the child is unable to maintain a satisfactory haemoglobin level. If left untreated the life span may be restricted to 3-5 years. The child requires frequent blood transfusions, which leads to accumulation of iron in the liver, heart and other organs. The only way to control this iron deposition is to use drugs called iron chelators. The treatment is long-drawn, expensive (Rs 5000-10000 per month) and emotionally taxing for the family. In addition, there are dangers of repeated blood transfusions that include transmission of hepatitis and HIV (which causes AIDS). Recently, bone marrow transplantation has been successfully performed in these children. This new modality has its limitations since it is expensive, it requires HLA matched donors, and carries a failure rate of 10-30%.
Thalassaemia minor - is a carrier state in which one of a pair of chromosomes carries the affected gene. These individuals are essentially healthy and have a normal life span. They do not require blood transfusions, although they may be slightly anaemic especially during stress periods like pregnancy. These individuals are capable of passing the gene to the next generation.
How is thalassaemia inherited?
If both parents have thalassaemia minor, then there is a 25% chance of their children having thalassaemia major, 50% will have thalassaemia minor and 25% will be normal. Each subsequent pregnancy carries the same risk.
How is thalassaemia diagnosed?
Diagnosis can be made by a blood test that shows anaemia. Certain types of haemoglobin like foetal haemoglobin and haemoglobin A2 are raised in their blood.
Can thalassaemia be prevented?
Thalassaemia can be prevented by: - Carrier screening - all married women should be screened either before pregnancy or during early pregnancy. If they have thalassaemia minor then their husbands must be checked. If both have thalassaemia minor then prenatal testing must be done. If the foetus is affected by thalassaemia major, the pregnancy may be terminated.
Prenatal detection (detection before the birth of the baby) - this can be done by sampling either the fluid in the sac around the baby (amniotic fluid) or by taking a blood sample of the foetus and testing for the thalassaemia gene. Chorion villus sampling can be performed between 9 and 18 weeks of pregnancy.
Are there any support groups for the care of thalassaemic children?
Thalassaemics India is a national, non-governmental, non-profit organization dedicated creating widespread awareness about thalassaemia and mobilizing resources for the benefit of patients from the needy sections of society.