About Sickle Cell

History of Sickle Cell

The existence of sickle cell disease was first reported around the beginning of the twentieth century when the medical world discovered microscopic oddly shaped red blood cells. In 1910, Dr. James Herrick in Chicago treated an individual with symptoms of pains in the stomach and joints, dizziness and general tiredness. Dr. Herrick examined the individual and discovered leg ulcers and acute chest syndrome. These symptoms were finally linked to a disease called sickle cell in 1917.

Dr. Janet Watson observed infants who had normal fetal hemoglobin at birth who later showed evidence of sickling of their blood cells when they began to produce adult hemoglobin at four to six months old. Dr. Linus Pauling in 1949 made the distinction between sickle cell disease hemoglobin (hemoglobin S) and normal hemoglobin (hemoglobin A).

Research for the disease did not really begin until about 1952 when researchers discovered that the inherited disease resided in a defect of the hemoglobin. The Congress of the United States passed a National Sickle Cell Anemia Control Act in 1972. The Act formed the sickle cell disease branch in the Heart, Lung and Blood Institute of the National Institute of Health. It also established ten comprehensive sickle cell centers throughout the United States to develop programs for research, education, screening, counseling and improved care of individual with sickle cell disease. Hence, newborns found to have sickle cell disease were given prophylactic penicillin until they were five years old.


What Is Sickle Cell Disease?

Sickle cell disease is an inherited blood disorder. It is not a virus and is not contagious. An individual acquires sickle cell disease from genes passed to him or her by both parents, much in the same way as blood type, hair color and texture, eye color and other physical traits are inherited.

Normal red blood cells are soft and round, flat and flexible; they can squeeze through tiny blood vessels (capillaries) with no problem. Hemoglobin is the protein in blood cells that carries oxygen as the red blood cells flow to all parts of the body. Ordinarily, the hemoglobin molecules exist as single units in the blood cell, much like beads inside a beanbag.

Individuals with sickle cell disease have a small change in their hemoglobin. Because of this change, when the red blood cell loses its oxygen to tissues of the body, the hemoglobin molecules begin sticking together like a beaded necklace. The stiff hemoglobin chains change the shape of the normally round blood cell to the “sickle” shape for which the disease is named. A sickle is a farm tool with the arc shape. It is used to cut weeds. When the sickle red blood cell returns to the lungs and picks up more oxygen, the hemoglobin molecules become unstuck and the red blood cell returns to its normal shape. With each trip through the body and back to the lungs, the cell eventually weakens and can no longer function.

Red blood cells with sickle hemoglobin (also known as hemoglobin S), can sometimes clump together and obstruct tiny blood vessels that nourish muscle and organ tissues in the body. Organ tissues that have blood flow blockages may eventually become damaged. This causes many of the complications of sickle cell disease.