Hemoglobin C, S-C, and E Diseases
Hemoglobin C, S-C, and E diseases are inherited conditions characterized by gene mutations that affect the hemoglobin (the protein that carries oxygen) in red blood cells, causing the cells to shape themselves abnormally and clump together. These red blood cells are destroyed more quickly than others, resulting in chronic anemia.
Hemoglobin C disease occurs mostly in blacks. One copy of the gene that causes hemoglobin C disease is present in 2 to 3% of blacks in the United States. However, people must inherit two copies of the abnormal gene to develop the disease.
In general, symptoms are few. Anemia varies in severity. People who have this disease, particularly children, may have episodes of abdominal and joint pain, an enlarged spleen, and mild jaundice, but they do not have severe crises, as occur in sickle cell disease.
Gallstones are a common complication of hemoglobin C disease.
Hemoglobin S-C disease occurs in people who have one copy of the gene for sickle cell disease and one copy of the gene for hemoglobin C disease. Hemoglobin S-C disease is more common than hemoglobin C disease, and its symptoms are similar to those of sickle cell disease but milder. However, people may have blood in the urine, an enlarged spleen, bleeding into the back of the eye (retinal hemorrhage), and damage to hip joint.
Blood tests are done for diagnosis of hemoglobin C and S-C disease and E disease. Doctors examine a sample of blood under a microscope. Red blood cells have various abnormal shapes, and other abnormalities can also be seen in the blood samples in people with these diseases.
Another blood test, called hemoglobin electrophoresis, is also done. In electrophoresis, an electrical current is used to separate the different types of hemoglobin and thus detect abnormal hemoglobin.
Treatment varies depending on the symptoms and their severity. Some people do not need treatment.
People with hemoglobin C disease may rarely need blood transfusions.
When treatment is needed for hemoglobin S-C disease, it is similar to that of sickle cell disease.
Most people with hemoglobin E disease do not require treatment. However, people with severe disease may need regular blood transfusions or removal of the spleen.