The most common type of abnormal hemoglobin and the basis of sickle cell trait and sickle cell anemia.
Hemoglobin S differs from normal adult hemoglobin (called hemoglobin A) only by a single amino acid substitution (a valine replacing a glutamine in the 6th position of the beta chain of globin). Recognition of this tiny change in the hemoglobin molecule marked the opening of molecular medicine.
- Hemoglobin, glycosylated
Hemoglobin to which glucose is bound. Glycosylated hemoglobin is tested to monitor the long-term control of diabetes mellitus. The level of glycosylated hemoglobin is increased in the red blood cells of persons with poorly controlled diabetes mellitus. Since the glucose stays attached to hemoglobin for the life of the red blood cell (normally about 120 […]
The presence of free hemoglobin in the urine, which may make the urine look dark. Normally, there is no hemoglobin in the urine. Hemoglobinuria is a sign of a number of abnormal conditions, such as bleeding and paroxysmal nocturnal hemoglobinuria.
The word “hemolysis” is made up of “hemo-“, blood + “lysis”, the disintegration of cells.
The word “hemolytic” is made up of “hemo-“, blood + “lytic”, the disintegration of cells.
- Hemolytic anemia
Anemia due to the destruction, rather than underproduction, of red blood cells. Hemolytic anemia can result from a medication reaction, from the immune system attacking the red blood cells (autoimmune hemolytic anemia), from destruction of blood cells passing through diseased heart valves, and other causes.