Adult haemoglobin A has 2 alpha and 2 beta chains. Beta thalassaemia is a monogenic, single gene haemoglobin defect (hemoglobinopathy) that is a result of reduced beta chains production resulting in decreased amount of adult haemoglobin (Hb A).
It can be seen in three main forms in certain at-risk communities – the carrier state (minor or trait) where the Hb is usually 9-11 gm% with only one of the two beta genes being affected. It is most often incidentally detected or as part of anaemia evaluation. Diagnosis is achieved by a CBC showing hypo micro anaemia with a raised A2 >3.5 on Hb electrophoresis or >4% on HPLC (High Performance Liquid Chromatography).
The second form is intermedia (now known as Non-Transfusion dependent Thalassemia or NTDT) where there is further reduction in beta chain production with further Hb A reduction but not as severe as major.
Patients have a lesser haemoglobin than the traits, usually 7-10 gm%, and may have some features of thalassaemia syndrome like prominent forehead, symptoms of anaemia and a hepatosplenomegaly. The third form is thalassaemia major, the most severe form of thalassaemia with an almost absent adult Hb due to severe defect in both the beta genes. Such children are detected usually by 6- 9 months of age due to severe anaemia resulting in improper growth, being pale or not active.
A CBC confirms a low Hb, usually in the range of
Prevention of thalassaemia major birth is more important and significantly more cost-effective to the family, community and nation at large rather than having them to go through the physical, psychosocial, emotional and financial burden of treating them once they are born. More aggressive awareness programs and education at community level is needed. The taboo of being a thalassaemia carrier (trait) should be removed from the minds of people.
Thalassemia major in children results in growth retardation, hemolytic (chipmunk) facies, hepatosplenomegaly and the need for regular lifelong blood transfusions, iron removing agents (chelation), management of various complications of the disease and the treatment including endocrine, cardiac and pancreatic dysfunction. This affects the quality of life and causes psychological issues in the patient.
However, if a thalassemia child is transfused regularly and ideally with a quality filtered blood to reduce leucocytes, it is possible for them to have a near normal life-span well beyond adulthood. Along the way, levels of ferritin to look for iron overload and oral iron chelation agent (medicines that remove excess iron from the blood though the urine) and checking for early organ damage by MRI of the heart, pancreas and liver should be performed to get the best results for a proper growth. In this way, we can still give good quality of life to thalassemia major patients.
Other than the option of transfusions and chelation, allogenic bone marrow transplantation (matched related or matched unrelated donor who is 10/10 HLA matched) can be a curative option for thalassemia major. It does come with several caveats including risks and costs, but these can be addressed appropriately by a transplant centre, which has protocols in place. We need more young donors to register in the bone marrow registries, so that this curative option is available to more children and adults living with thalassaemia.
Recently the western countries have got another curative option, gene therapy for beta thalassemia, which has only been recommended for patients who do not have an HLA matched donor. Though the results are quite encouraging, it is very early days to assess long term benefit or side effects of this therapy.
A third option is a drug Luspatercept that improves the hemoglobin in thalassemia major and makes them relatively transfusion independent. It is expensive, injectable, needs long term treatment and is not currently available in India, but can be legally obtained from abroad at a cost.
People living with thalassemia had intermittent blood shortages in the covid times due to reduced voluntary donations and many centers reduced their Hb target temporarily below 9 gm%. Thanks to intermittent camps, this shortage could be overcome. A recent directive that donors can donate 15 days after taking the vaccine has improved the blood donor pool. People living with thalassemia were allowed to go to work with all standard precautions but school and college going children were told to refrain from meeting people especially with symptoms or being in crowds, and asked to stay at home as much as possible, with travel to transfusion centres only when it was needed to take blood. They were counselled by video consultation and educational programs about corona virus and its ill effects and any issues that they had related to their disease. People living with thalassemia are relatively more immunocompromised, so the Day Care centres followed all precautions during transfusion.
Better awareness in the community, proper testing or thalassaemia of at-risk people, not hiding the thalassaemia reports at the time of marriage and better counselling at the time of pregnancy if both are traits can help prevent thalassaemia major births.
World Thalassemia Day is celebrated every year on May 8th.
(The author is a Hematologist at Global Hospitals in Parel, Mumbai
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