Sickle Cell Anemia

What Is It?

Sickle cell anemia is an inherited blood disorder.

It causes:

  • Chronic destruction of red blood cells

  • Episodes of intense pain

  • Vulnerability to infections

  • Organ damage

  • In some cases, early death

Hemoglobin is a protein in red blood cells that carries oxygen. People with sickle cell anemia inherit a defective type of hemoglobin. When oxygen levels inside a red blood cell get low, the defective hemoglobin forms long rods. These rods stretch the red blood cells into long, abnormal "sickle" shapes. In contrast, normal red blood cells are disc-shaped.

Sickle-shaped red blood cells cannot easily pass through the body's blood vessels. Instead, they clog blood vessels. They block the flow of blood and cut off the oxygen supply to tissues and organs.

This lack of oxygen can damage the body's organs and limbs. It causes severe pain in any affected area.

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