Get Information about Autoimmune Hemolytic Anemia
Anemia is a blood disorder characterized by deficient red blood cells (RBCs) . Anemia can be caused by congenital disorders; blood loss; nutrient deficiencies; inadequate RBC production; and increased destruction or lysis of RBCs. In lysis or hemolysis, the term used for lysis of RBCs, the cell's outer membrane is ruptured. Hemolysis releases hemoglobin, the blood protein that carries oxygen to tissues, from RBCs, destroying them. Normally, RBCs survive for about 120 days and then begin to disintegrate. New RBCs are constantly produced in the bone marrow and replace the old, disintegrating cells. This cell lifespan or programmed cell death is known as apoptosis. Anemias associated with hemolysis are known as hemolytic anemias.
Autoimmune hemolytic anemia is a condition in which the immune system mistakenly identifies an individual’s healthy red blood cells for foreign and harmful agents. This results in the immune system’s attack of the red blood cell, causing them to disintegrate faster than they can be replaced by the bone marrow. This process, which may follow a mononucleosis infection, is also referred to as hemolysis, or the breaking up of red blood cells.
Autoimmune hemolytic anemia is a condition in which your body’s immune system mistakenly attacks its own red blood cells, causing them to disintegrate (hemolyze). This can be a serious, even lethal, condition that requires care from your doctor.
Idiopathic autoimmune hemolytic anemia is a drop in the number of red blood cells due to a problem with the body's defense (immune) system.
There are many causes of hemolysis, the breaking up of red blood cells. Some are congenital (eg, sickle cell disease), some are due to other diseases, and some are caused by drugs, but they all lead to anemia. The autoimmune hemolytic anemias, of which there are many types, occur when antibodies attack red blood cells.
Destruction of red blood cells by autoantibodies may occur suddenly, or it may develop gradually. In some people, the destruction may stop after a period of time; whereas in other people, it persists and becomes chronic. There are two main types of autoimmune hemolytic anemia: warm antibody hemolytic anemia and cold antibody hemolytic anemia. In the warm antibody type, the autoantibodies attach to and destroy red blood cells at temperatures equal to or in excess of normal body temperature.
How does autoimmune hemolytic anemia develop?
In this disorder, an abnormal immune reaction causes the body to produce antibodies that attack red blood cells and encourage their destruction in the spleen. Certain drugs, such as penicillin, methyldopa or quinine, could trigger this disorder. Antibodies that attack red blood cells may also occur in people who have chronic lymphocytic leukemia or other autoimmune diseases.
The oxygen-carrying molecule in red blood cells is hemoglobin (pronounced HEE-muh-glo-bin). Hemoglobin is a large, complex molecule. It contains an atom of iron at its center. Iron attaches itself easily to oxygen atoms. It is the iron in hemoglobin that actually carries oxygen to cells.
A disease characterized by increased destruction of red blood cells (erythrocytes) by the dog's own immune system, canine autoimmune hemolytic anemia (AIHA) is one of the most common blood (hematologic) disorders affecting canines. Though much attention has been given recently to AIHA due to evidence linking the process of vaccinating with the manifestation of this sometimes life-threatening disease, immunization is only one potential cause for this condition.