In the United States, sickle cell anemaia occurs mostly among African Americans. About 1 in 12 African Americans are carriers of the abnormal trait. Carriers usually have no symptoms. However, if two carriers have children, there is a 1 in 4 chance that a child will have the disease. Infections, stress, loss of body water, or low blood oxygen can provoke a sickle cell crisis.
Crisis usually entails sever pain in the abdomen, chest, muscles, or bones.
There may be jaundice, dark urine, or a low fever. There is an increased risk of a blood infection. The crisis can last from a day or two to several weeks. In another type of crisis, production of new red blood cells drops sharply. Infants may have still another type of crisis in which massive amounts of red blood cells are suddenly trapped in the liver and spleen.