Write a note on
1.Pernicious Anaemia
2.Sicke Cell Anaemia
3.Aplastic Anaemia
1. Pernicious anemia is a condition in which the body can't make enough healthy red blood cells because it doesn't have enough vitamin B12.
Vitamin B12 is a nutrient found in some foods. The body needs this nutrient to make healthy red blood cells and to keep its nervous system working properly.
People who have pernicious anemia can't absorb enough vitamin B12 from food. This is because they lack intrinsic factor, a protein made in the stomach. A lack of this protein leads to vitamin B12 deficiency.
Other conditions and factors also can cause vitamin B12 deficiency. Examples include infections, surgery, medicines, and diet. Technically, the term "pernicious anemia" refers to vitamin B12 deficiency due to a lack of intrinsic factor. Often though, vitamin B12 deficiency due to other causes also is called pernicious anemia
2.Sickle cell anemia is a disease which is caused by a mutation in which the amino acid at 6th position (glutamine) in the beta chain of hemoglobin is replaced by valine. The major characteristics of this disease are anemia (less functional RBCs) and a tendency of the red blood cells to change shape at low oxygen concentrations. The sickle cells are useless and have to be broken down. They tend to jam in capillaries and small blood vessels and prevent normal blood flow. A whole range of secondary symptoms is possible as a result. The kidneys and joints are particularly affected. The blocking of blood vessels causes pain in arms, legs, back and stomach which can be quite severe. Joints may become stiff and painful and hands and feet may swell.
3. Aplastic anemia is a condition occurs when body stops producing enough new blood cells. Symptoms are: fatigue, higher risk of infections and uncontrolled bleeding. Treatment include blood transfusions (in mild conditions), medications (serious cases) and in severe cases bone marrow transplantation. In severe aplastic anemia, blood cell counts are extremely low which is life-threatening.
Regards