Normal Function of Red Blood Cells

• Normal red blood cells
  
  Blood contains red and white blood cells. Red blood cells use hemoglobin, a protein that contains iron, to transport oxygen from the lungs to the rest of the body. Normal red blood cells are disc-shaped and are flexible enough to maneuver through small blood vessels to deliver oxygen throughout the body.
  
  

Sickle Cell Anemia

• Abnormal red blood cells
  
  A genetic mutation causes abnormal hemoglobin, called "hemoglobin S," to form in the red blood cells of those with sickle cell anemia. This abnormal hemoglobin makes red blood cells look like sickles or crescents, and they do not carry oxygen as well as normal hemoglobin.
  Epidemiologists believe that the mutation developed in Africa as a result of infections with malaria. Because parasites that cause malaria cannot infect sickle cells, people with sickle cell anemia survived malaria to pass on their genes to future generations.
  
  

Anemia and Hypoxia

• Cells with hemoglobin S are destroyed by the body at a higher rate than normal blood cells, which leaves fewer cells to carry oxygen through the body, a condition called "hypoxia." Patients with hypoxia typically feel tired and achy, with some pain unbearable. Also, the increased destruction of red blood cells produces an increase in bilirubin, which may cause jaundice and darkened urine.
  
  

Vascular Complications

• Diagram of capillary blood vessels
  
  Because sickle cells do not flow smoothly through small blood vessels, organs that have the most, such as the eyes, lungs and penis, can be damaged as more and more are stuck in the capillaries. This can damage the lungs and kidneys and cause blindness and erectile dysfunction.
  
  

Stroke and Heart Attacks

• Like other organs, the brain and heart depend on the oxygen that travels through blood in small arteries. When sickle cells block these arteries, the organs that do not receive oxygen can die in a few minutes. A stroke occurs when there is a blockage in the brain, while a heart attack occurs when the blockage is in the heart.
  
  

Avoiding Sickle Cell Anemia Complications

• People with sickle cell anemia require regular medical care and must live healthy lifestyles. This includes regular blood tests and evaluations for organ damage. Those suffering from the disease should avoid exercises and situations that place a heavy burden on the body's ability to deliver oxygen. Also, they should maintain a diet low in saturated fat, cholesterol and sodium to reduce the chances of developing hardening of the arteries.