Thalassemia And Sickle Cell Anemia

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It’s a type of blood disorder which affects the body’s ability to produce hemoglobin and red blood cells. In this disease, patient has less number of red blood cells in their bodies and having less hemoglobin as compared to normal human beings. It results in to development of anemia and fatigue. Thalassemia is caused by variant or missing genes that affect how the body makes hemoglobin. It is a hereditary disease.
What is hemoglobin?
It is a red colour protein that carries the oxygen and nutrients which transports it to the rest of the body. It’s a spongy material inside some of our bones - bone marrow - uses iron that our body takes from food and makes hemoglobin. Two alpha globin and two beta globin protein chains make up hemoglobin.
Types of Thalassemia
1. Alpha Thalassemia = α-Thalassemia is caused by reduced or absent synthesis of α-globin chains. The patient’s hemoglobin does not produce enough alpha proteins, so the fewer alpha chain proteins are produced.
2. Beta Thalassemia = Β-Thalassemia is caused by reduced or absent synthesis of ß-globin chains. We need two globin genes to make beta globin chains. We (all human beings) get one from each parent. If one or two of these genes are faulty, it produces beta Thalassemia.
 Severity of beta Thalassemia also depends on how many genes are mutated:
If one globin gene is mutated - the patient may have Beta Thalassemia minor.
If both globin genes are mutated - the patient may have either moderate or severe symptoms (Colley's anemia).
Causes of Thalassemia
Thalassemia can make the bone marrow expand, which causes bones to widen. This can result in abnormal bone structure, especially in the face and skull.
Cardiovascular illness.
People with Thalassemia have a high risk of infection.
Due to Thalassemia children’s growth become slowed i.e. stunted.
Thalassemia results into congestive heart failure and abnormal heart rhythms (arrhythmias).
In severe form patient needs regular blood transfusion.
Risk of organ failure, liver damage, heart failure
Benefits of Thalassemia
The inherited disease of red blood cells may confer a degree of protection against malaria.
Treatment options for Thalassemia
Bone marrow transplantation also called steam cell transplantation
Blood transfusion = this is done to replenish hemoglobin and red blood cell levels. Patients with moderate to severe Thalassemia will have to repeat transfusions every 4 months, while those with more severe disease may require transfusions every two to four weeks.
Iron chelating = involves removing excess iron from the bloodstream. Sometimes blood transfusions can cause iron overload. Iron overload is bad for the heart and some other organs
Some patients with bone abnormalities may require surgery.
Sickle cell anemia
It is a hereditary (This means that the gene can be passed on from a parent carrying it to male and female children) disease in which human body makes sickle shaped (the red blood cells are shaped like a crescent) red blood cells. In Sickle cell anemia, sickle cells contain abnormal hemoglobin called sickle hemoglobin. These cells are sticky. They tend to block blood flow in blood vessels.
Sickle cell anemia may differ from person to person. The term disease is applied because the inherited abnormality causes a pathological condition that can lead to death and severe complications.
Mutated genes related for sickle cell dieses
Mutation in the HBB gene causes sickle cell disease. Hemoglobin consists of four protein subunits, typically, two Subunits called alpha-globin and two subunits called beta-globin. The HBB gene provides instructions for making beta-globin. Various versions of beta-globin result from different mutations in the HBB gene.
Blood and blood marrow transplant ( but it can cure only small amount people)
Babies and young children with sickle cell disease must take a daily dose of penicillin to prevent potentially deadly infections. Patients also take folic acid, which helps build new red blood cells.
Doctors advise people with sickle cell disease to get plenty of rest, drink lots of water, and avoid too much physical activity.
Unlike normal red blood cells, which can live for 120 days, sickle-shaped cells live only 10 to 20 days.
Sickle cell disease is most common among people from Africa, India, the Caribbean, the Middle East, and the Mediterranean.
The high prevalence of the defective gene in these regions may be due to the fact that carriers of a mutation in the beta-subunit of hemoglobin are more resistant to malaria. (Malaria is a disease caused by a parasite that is transmitted to a person when they are bitten by an infected mosquito. The sometimes fatal disease is common in hot countries, and causes recurring chills and fever.)
Proper testing of Thalassemia and the Sickle Cell anemia if done can cost around 15,000 rupees.
But government in order to minimize this amount, has recently launched a low-cost, indigenously-manufactured Thalassemia and Sickle Cell diagnostic kit that will simplify the identification of seven common beta-thalassemia mutations and two common abnormal haemoglobins common in India.
The kit is going to be made available at approximately Rs 400 in the public health facilities up to district level.
Reverse Dot Blot Hybridization (RDB) Kit for Thalassemia has been launched by the Health and Family Welfare Ministry, has been developed by scientists of the National Institute of Immuno Haematolgoy (NIIH) and the Indian Council for Medical research (ICMR).
It is being domestically manufactured by IMGENEX Ltd.
The role of the molecular kit is to meet the need for affordable and sensitive tests for the diagnosis of affected children, and pre-natal diagnosis in the first trimester.
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