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. These red blood cells are destroyed more quickly than others, resulting in chronic anemia.
(See also Overview of Anemia and Sickle Cell Disease.)
Hemoglobin C disease
Hemoglobin C disease occurs mostly in people with African or Black American ancestry. One copy of the gene that causes hemoglobin C disease is present in 2 to 3% of people with African or Black American ancestry in the United States. However, people must inherit 2 copies of the abnormal gene to develop the disease.
In general, symptoms are few. Anemia varies in severity. People who have this disease may have an enlarged spleen and mild jaundice, but they do not have crises, as occur in sickle cell disease.
Gallstones are a common complication of hemoglobin C disease.
Hemoglobin S-C disease
Hemoglobin S-C disease is a form of sickle cell disease and occurs in people who have 1 copy of the gene for sickle cell disease and 1 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 anemia, but acute pain episodes and life-threatening complications occur less frequently or develop later in life. However, people may develop kidney disease, an enlarged spleen, bleeding into the back of the eye (retinal hemorrhage), and damage to the hip joint.
Hemoglobin E disease
Hemoglobin E disease affects primarily people of Southeast Asian ancestry. This disease causes mild anemia but none of the other symptoms that occur in sickle cell disease and hemoglobin C disease.
Diagnosis of Hemoglobin C, S-C, and E Diseases
Blood tests
Hemoglobin electrophoresis
Blood tests are done for diagnosis of hemoglobin C, S-C, and E diseases. 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. High-performance liquid chromatography is also performed to distinguish these variants in hemoglobin.
Treatment of Hemoglobin C, S-C, and E Diseases
Occasionally blood transfusions
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, but usually they do not require treatment.
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.