Sickle Cell Anemia

Sickle cell anemia is the most common blood disorder that affects hemoglobin. Hemoglobin is the part of red blood cells that carries oxygen throughout the body. In patients with sickle cell anemia, abnormal hemoglobin causes the red blood cells to become misshapen, so that instead of being round, they are shaped like crescents, or sickles. While round cells travel easily through the blood vessels, sickle-shaped cells get stuck, resulting in impeded blood flow, pain, increased risk of infection, and possible organ damage.

The symptoms of patients with sickle cell anemia may range from mild to severe. In the United States, newborns routinely undergo blood tests for this disorder.The disease is more prevalent in certain parts of the world; in the United States it is most common among African Americans.

Causes of Sickle Cell Anemia

Sickle cell anemia is an inherited disease. In order for a person to be born with the condition, a gene must be inherited from each parent. Individuals who inherit only one defective gene have a condition known as sickle cell trait. While most people with sickle cell trait are asymptomatic, they still carry the recessive gene and may, therefore, pass the disease on to their offspring. Though some individuals with sickle cell trait experience medical complications, most are asymptomatic.

Symptoms of Sickle Cell Anemia

While affected infants are born with this disease, many do not show any signs of having the disorder until they are about 4 months old. The most common symptoms of sickle cell anemia are anemia, pain, fatigue, and swelling of the hands and feet. Other symptoms may include:

  • Headaches
  • Shortness of breath
  • Dizziness
  • Cold hands and feet
  • Pallor of skin and mucous membranes
  • Jaundice

Patients experience sickle cell crises when blood flow is blocked in a particular part of the body. Crises may last for hours or more than a week and are of variable frequency. Chronic or acute episodes can damage vital organs, are more likely to occur in adults than in children, and may be precipitated by infections or by dehydration.

Complications of Sickle Cell Anemia

Growth patterns are affected by sickle cell anemia. Children with this disease grow more slowly than their peers and may reach puberty at an older age. Adults with the disorder tend to be thinner and of smaller stature than adults without this disorder. Other complications of sickle cell anemia may occur in any part of the body, depending on which blood vessels are affected and may include:

  • Visual problems
  • Leg ulcers
  • Acute chest syndrome
  • Pulmonary Hypertension
  • Gallstones
  • Priapism (abnormally prolonged erection)
  • Stroke
  • Frequent infections
  • Hand-foot syndrome (swelling of the hand and feet)
  • Splenic crisis

When sickle cell anemia results in decreased blood flow to several areas of the body at once, it can result in life-threatening multiple organ failure.

Treatment of Sickle Cell Anemia

There is no specific treatment for sickle cell anemia, but a small number of patients can be cured by blood and marrow stem cell transplants. Because of screenings of newborns for the problem, many children with this disorder have a better chance of surviving and leading normal lives than ever before. Special care is taken to vaccinate affected babies as early as possible, to administer antibiotics at the first sign of infections, and to educate parents on methods to effectively cope with the disease.

For patients with active symptoms of sickle cell anemia, treatments include attempts to relieve pain, and to prevent and treat infections. Efforts are made to keep crises from developing and, if they do develop, to prevent organ damage, strokes, and other complications. While research to cure this devastating disease continues, treatments now include:

  • Over-the-counter pain medication
  • Opioids
  • Oxygen therapy
  • Intravenous fluids
  • Antibiotics
  • Hydroxyurea

The oral medication known as hydroxyurea works by stimulating the body to produce fetal hemoglobin, or hemoglobin F. Fetal hemoglobin helps prevent red blood cells from sticking and also lessens anemia. While hydroxyurea is not effective for all patients with sickle cell anemia, research shows that many patients who take it daily have positive results, including:

  • Fewer hospital visits
  • Fewer sickle cell crises
  • Fewer incidents of acute chest syndrome
  • Fewer blood transfusions

Patients taking hydroxyurea must be monitored carefully, however, because this medication may have serious side effects.

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