what is sickle cell disorder?
a severe hereditary form of anemia in which a mutated form of hemoglobin distorts the red blood cells into a crescent shape at low oxygen levels. It is most common among those of African descent.
People may experience:
- Pain areas: in the joints
- Pain types: can be sudden in the chest
- Whole body: dizziness, fatigue, low oxygen in the body, or malaise
- Urinary: inability to make concentrated or dilute urine or blood in urine
- Also common: abnormal breakdown of red blood cells, delayed development, inflamed fingers or toes, pallor, shortness of breath, or yellow skin and eyes
medications, blood transfusions, and rarely a bone-marrow transplant.
In the United States, sickle cell disease is most prevalent among African Americans. About one in 12 African Americans and about one in 100 Hispanic Americans carry the sickle cell trait, which means they are carriers of the disease.
Sickle cell disease is caused by a mutation in the hemoglobin-Beta gene found on chromosome 11. Hemoglobin transports oxygen from the lungs to other parts of the body. Red blood cells with normal hemoglobin (hemoglobin-A) are smooth and round and glide through blood vessels.
In people with sickle cell disease, abnormal hemoglobin molecules - hemoglobin S - stick to one another and form long, rod-like structures. These structures cause red blood cells to become stiff, assuming a sickle shape. Their shape causes these red blood cells to pile up, causing blockages and damaging vital organs and tissue.
Sickle cells are destroyed rapidly in the bodies of people with the disease, causing anemia. This anemia is what gives the disease its commonly known name - sickle cell anemia.
The sickle cells also block the flow of blood through vessels, resulting in lung tissue damage that causes acute chest syndrome, pain episodes, stroke and priapism (painful, prolonged erection). It also causes damage to the spleen, kidneys and liver. The damage to the spleen makes patients - especially young children - easily overwhelmed by bacterial infections.
A baby born with sickle cell disease inherits a gene for the disorder from both parents. When both parents have the genetic defect, there's a 25 percent chance that each child will be born with sickle cell disease.
If a child inherits only one copy of the defective gene (from either parent), there is a 50 percent chance that the child will carry the sickle cell trait. People who only carry the sickle cell trait typically don't get the disease, but can pass the defective gene on to their children.