What Is Anemia?
Anemia (uh-NEE-me-eh) is a condition in which your blood has a lower than normal number of red blood cells. This condition also can occur if your red blood cells don’t contain enough hemoglobin (HEE-muh-glow-bin). Hemoglobin is an iron-rich protein that gives blood its red color. This protein helps red blood cells carry oxygen from the lungs to the rest of the body.
If you have anemia, your body doesn’t get enough oxygen-rich blood. As a result, you may feel tired and have other symptoms. With severe or long-lasting anemia, the lack of oxygen in the blood can damage the heart, brain, and other organs of the body. Very severe anemia may even cause death.
What Causes Anemia?
The three main causes of anemia are:
- Blood loss
- Lack of red blood cell production
- High rates of red blood cell destruction
Some people have anemia due to more than one of these factors.
Blood Loss
Blood loss is the most common cause of anemia, especially iron-deficiency anemia. Blood loss can be short term or persist over time.
Heavy menstrual periods or bleeding in the digestive or urinary tract can cause blood loss. Surgery, trauma, or cancer also can cause blood loss.
If a lot of blood is lost, the body may lose enough red blood cells to cause anemia.
Lack of Red Blood Cell Production
Both acquired and inherited conditions and factors can prevent your body from making enough red blood cells. “Acquired” means you aren’t born with the condition, but you develop it. “Inherited” means your parents passed the gene for the condition on to you.
Examples of acquired conditions and factors that can prevent your body from making enough red blood cells include diet, hormones, some chronic (ongoing) diseases, and pregnancy.
Aplastic anemia also can prevent your body from making enough red blood cells. This condition can be acquired or inherited.
Diet
A diet that lacks iron, folic acid (folate), or vitamin B12 can prevent your body from making enough red blood cells. Your body also needs small amounts of vitamin C, riboflavin, and copper to make red blood cells.
Conditions that make it hard for your body to absorb nutrients also can cause your body to make too few red blood cells.
Hormones
Your body needs the hormone erythropoietin (eh-rith-ro-POY-eh-tin) to make red blood cells. This hormone stimulates the bone marrow to make these cells. A low level of this hormone can lead to anemia.
Diseases and Disease Treatments
Chronic (long-term) diseases, like kidney disease and cancer, can make it hard for the body to make enough red blood cells.
Some cancer treatments may damage the bone marrow or damage the red blood cells’ ability to carry oxygen. If the bone marrow is damaged, it can’t make red blood cells fast enough to replace the ones that died or were destroyed.
People who have HIV/AIDS may develop anemia due to infections or medicines used to treat their diseases.
Pregnancy
Anemia can occur during pregnancy due to low levels of iron and folic acid (folate) and changes in the blood.
During the first 6 months of pregnancy, the fluid portion of a woman’s blood (the plasma) increases faster than the number of red blood cells. This dilutes the blood and can lead to anemia.
Aplastic Anemia
Some infants are born without the ability to make enough red blood cells. This condition is called aplastic anemia. Infants and children who have aplastic anemia often need blood transfusions to increase the number of red blood cells in their blood.
Acquired conditions or factors, such as certain medicines, toxins, and infectious diseases, also can cause aplastic anemia.
High Rates of Red Blood Cell Destruction
Both acquired and inherited conditions and factors can cause your body to destroy too many red blood cells.
One example of an acquired condition that can cause your body to destroy too many red blood cells is an enlarged or diseased spleen. The spleen is an organ that removes worn-out red blood cells from the body. If the spleen is enlarged or diseased, it may remove more red blood cells than normal, causing anemia.
Examples of inherited conditions that can cause your body to destroy too many red blood cells include sickle cell anemia, thalassemias, and lack of certain enzymes. These conditions create defects in the red blood cells that cause them to die faster than healthy red blood cells.
Hemolytic anemia is another example of a condition in which your body destroys too many red blood cells. Inherited conditions can cause this type of anemia. Acquired conditions or factors, such as immune disorders, infections, certain medicines, or reactions to blood transfusions, also can cause hemolytic anemia.
How is anemia treated?
The treatment of the anemia varies greatly. First, the underlying cause of the anemia should be identified and corrected. For example, anemia as a result of blood loss from a stomach ulcer should begin with medications to heal the ulcer. Likewise, surgery is often necessary to remove a colon cancer that is causing chronic blood loss and anemia.
Sometimes iron supplements will also be needed to correct iron deficiency. In severe anemia, blood transfusions may be necessary. Vitamin B12 injections will be necessary for patients suffering from pernicious anemia or other causes of B12 deficiency.
In certain patients with bone marrow disease (or bone marrow damage from chemotherapy) or patients with kidney failure, epoetin alfa (Procrit, Epogen) may be used to stimulate bone marrow red blood cell production.
If a medication is thought to be the culprit, then it should be discontinued under the direction of the prescribing doctor.