Symptoms of the condition appear at about six months of age and may include enlargement of the abdomen and heart and painful swelling of the hands and feet. In adolescence, sexual maturation may be delayed. The disturbances in blood flow associated with the disease also dispose affected persons to infections and leg ulcers. These symptoms are due to the altered hemoglobin, which changes shape when the amount of oxygen in the blood is reduced for any reason. The red blood cell in which the hemoglobin is contained changes its shape as well, from round to crescent (sickle shaped). The sickle-shaped red cells interfere with normal blood flow by plugging up small blood vessels.
Sickle-cell anemia occurs when an individual inherits a sickle-cell gene from each parent. …
