An Overview of Sickle Cell Disease

Sickle cell disease is the most common inherited blood disorder in the world, and some 100,000 Americans have sickle cell disease.

Sickle cell disease is a term used to describe a small variety of hemoglobin disorders. These disorders are characterized by a large amount of hemoglobin S in the blood when compared to normal adult hemoglobin. Although all types share similarities, some differences may impact your treatment plan and overall health.

Sickle hemoglobin disorders include, but are not limited to:

  • sickle cell anemia
  • hemoglobin SC disease
  • hemoglobin SD disease
  • hemoglobin SO-Arab
  • sickle beta thalassemia syndromes

Sickle cell disease can affect people of any ethnicity, but it primarily affects people of African descent.

- People of African, Mediterranean, East Indian, or Latin American descent are most likely to have sickle cell disease
- About one in 400 African-Americans have sickle cell disease
- More than 1,000 babies are born with sickle cell disease each year in the United States

When you have sickle cell disease, your body’s red blood cells become crescent- or sickle-shaped because they do not receive enough oxygen or become dehydrated. Once oxygen is restored, your cells return to their normal round shape, but over time they become fragile and stay in the sickle shape.

Sickled cells are hard, sticky, and get trapped in small blood vessels. The sickled cells can block blood flow to the tissues, causing pain and organ damage. This pain, known as a vaso-occlusive crisis, is the most common complication of sickle cell disease.


People with sickle cell disease may also have ongoing anemia, or a low red blood cell count in the body.

Because sickled cells do not live as long as normal blood cells, patients with sickle cell disease often do not have normal amounts of red blood cells in their bodies. Their sickled red blood cells are not able to carry enough oxygen throughout the body, which can cause damage over time.