Hemolytic anemia (HEE-moh-lit-ick uh-NEE-me-uh) is a condition in which red blood cells are destroyed and removed from the bloodstream before their normal lifespan is over.
Red blood cells are disc-shaped and look like doughnuts without holes in the center. These cells carry oxygen to your body. They also remove carbon dioxide (a waste product) from your body.
Red blood cells are made in the bone marrow—a sponge-like tissue inside the bones. They live for about 120 days in the bloodstream and then die.
White blood cells and platelets (PLATE-lets) also are made in the bone marrow. White blood cells help fight infections. Platelets stick together to seal small cuts or breaks on blood vessel walls and stop bleeding.
When blood cells die, the body's bone marrow makes more blood cells to replace them. However, in hemolytic anemia, the bone marrow can't make red blood cells fast enough to meet the body's needs.
Hemolytic anemia is a type of anemia. The term "anemia" usually refers to a condition in which the blood has a lower than normal number of red blood cells.
Anemia also can occur if your red blood cells don't contain enough hemoglobin (HEE-muh-glow-bin). Hemoglobin is an iron-rich protein that carries oxygen from the lungs to the rest of the body.
Anemia has three main causes: blood loss, lack of red blood cell production, or high rates of red blood cell destruction.
Hemolytic anemia is caused by high rates of red blood cell destruction. Many diseases, conditions, and factors can cause the body to destroy its red blood cells.
These causes can be inherited or acquired. "Inherited" means your parents passed the gene(s) for the condition on to you. "Acquired" means you aren't born with the condition, but you develop it. Sometimes the cause of hemolytic anemia isn't known.
There are many types of hemolytic anemia. Treatment and outlook depend on what type you have and how severe it is. The condition can develop suddenly or slowly. Symptoms can range from mild to severe.
Hemolytic anemia often can be successfully treated or controlled. Mild hemolytic anemia may need no treatment at all. Severe hemolytic anemia requires prompt and proper treatment, or it may be fatal.
Inherited forms of hemolytic anemia are lifelong conditions that may require ongoing treatment. Acquired forms of hemolytic anemia may go away if the cause of the condition is found and corrected.
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