Hemoglobin failure, or abnormal hemoglobin (such as that of sickle-cell disease). The ability of each hemoglobin molecule to carry oxygen is normally modified by altered blood pH or CO, causing an altered oxygen–hemoglobin dissociation curve. However, it can also be pathologically altered in, e.g., carbon monoxide poisoning. Decrease of hemoglobin, with or without an absolute decrease of red blood cells, leads to symptoms of anemia. Anemia has many different causes, although iron deficiency and its resultant iron deficiency anemia are the most common causes in the Western world. As absence of iron decreases heme synthesis, red blood cells in iron deficiency
Hemoglobin C 28–44% of total hemoglobin (Hb) is HbC, and no anemia develops. In homozygotes, nearly all Hb is in the HbC form, resulting in mild hemolytic anemia. Physical examination may show an enlarged spleen. Tests that may be done include: Complete Blood Count (CBC), Hemoglobin electrophoresis, Peripheral blood smear, and Blood hemoglobin. Genetic counseling may be appropriate for high-risk couples who wish to have a baby. Usually no treatment is needed. Folic acid supplementation may help produce normal red blood cells and improve the symptoms of anemia Overall, hemoglobin C disease is one of the more benign hemoglobinopathies. Mild-to-moderate reduction in