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Disease: Sickle cell disease

Brief Description: Sickle cell disease is an inherited form of anemia. As in other types of anemia, in sickle cell disease there are not enough healthy red blood cells (RBCs) to carry adequate oxygen to all the cells of the body.

Cause: Sickle cell disease is a genetic disease caused by an abnormal type of hemoglobin called hemoglobin S. Hemoglobin S distorts the shape of red blood cells, especially when oxygen levels are low.

In someone who has sickle cell disease, the RBCs are distorted. Instead of the smooth, circular, biconcave shape of normal RBCs, some of the cells are shaped like crescents. The crescent-shaped cells can clog small blood vessels.

Sickle cell disease is diagnosed by examining cells under a microscope and with a blood test.

Appearance of RBCs: In sickle cell disease, some of a person’s RBCs have a characteristic shape that can be observed under a microscope. Sickle cells are crescent shaped—or shaped like the tool called a “sickle.”

In an individual with sickle cell disease,

Sickle cells are destroyed rapidly in the body, causing anemia, jaundice, and gallstones.

The sickle cells also block the flow of blood through vessels, resulting in lung tissue damage, pain episodes, and strokes. These cells also cause damage to most organs including the spleen, kidneys, and the liver. Patients with sickle cell disease, especially young children, with damage to the spleen can be easily overwhelmed by certain bacterial infections.

Symptoms may include the following:

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