Aplastic Anemia: Causes

What causes aplastic anemia?

Aplastic anemia is caused by destruction of the blood-forming stem cells in your bone marrow. These stem cells normally develop into three types of blood cells: red blood cells, white blood cells, and platelets.

Most research suggests that stem cell destruction occurs because the body's immune system attacks its own cells by mistake.

Normally, the immune system attacks only foreign substances. When your immune system attacks your own body, you are said to have an autoimmune disease. Aplastic anemia is generally thought to be an autoimmune disease. Other autoimmune diseases include rheumatoid arthritis and lupus. Aplastic anemia can be acquired or hereditary.

  • Acquired aplastic anemia can begin any time in life. About 75 out of 100 cases of acquired aplastic anemia are idiopathic. This means they have no known cause.
  • Hereditary aplastic anemia is passed down through the genes from parent to child. It is usually diagnosed in childhood and is much less common than acquired aplastic anemia. People who develop hereditary aplastic anemia may have other genetic or developmental abnormalities.
  • For instance, certain inherited conditions can damage the stem cells and lead to aplastic anemia. Examples include Fanconi anemia, Shwachman-Diamond syndrome, dyskeratosis (DIS-ker-ah-TO-sis) congenita, and Diamond-Blackfan anemia.

About 25 out of 100 cases of acquired aplastic anemia can be linked to one of several causes. These include:

  • Toxins, such as pesticides, arsenic, and benzene
  • Radiation and chemotherapy used to treat cancer
  • Treatments for other autoimmune diseases, such as lupus and rheumatoid arthritis
  • Pregnancy - sometimes, this aplastic anemia improves on its own after the woman gives birth
  • Infectious dieases, such as hepatitis, Epstein-Barr virus, cytomegalovirus (si-to-MEG-ah-lo-VI-rus), parvovirus B19, and HIV.

Sometimes, cancer from another part of the body can spread to the bone and cause aplastic anemia.