Different diseases, conditions, or factors can cause each type.
Inherited
With the inherited type, parents pass the genes for the condition on to their children. Two common causes of this type of anemia are sickle cell anemia and thalassemia. These conditions create red blood cells that don't live as long as normal red blood cells.
Acquired
With this type of anemia, you are not born with a certain condition. Your body makes normal red blood cells, but they are later destroyed. This may happen because of:
- Certain infections, which may be viral or bacterial.
- Medicines, such as penicillin, antimalarial medicines, sulfa medicines, or acetaminophen.
- Blood cancers.
- Autoimmune disorders, such as lupus, rheumatoid arthritis, or ulcerative colitis.
- Certain tumors.
- An overactive spleen (hypersplenism).
- Mechanical heart valves that may damage red blood cells as they leave the heart.
- A severe reaction to a blood transfusion.