Hemoglobin Electrophoresis
Alternate Names : Hb Electrophoresis, Hgb Electrophoresis
Definition Hemoglobin electrophoresis is a test that measures the different types of hemoglobin (Hb) in the blood. (See also hemoglobin; glycosylated hemoglobin.)
Why is the Test Performed?
This test is performed when a disorder associated with abnormal forms of hemoglobin (hemoglobinopathy) is suspected.
Although many different hemoglobin molecules have been described, the most common ones are HbA, HbA2, HbF, HbS, HbC, Hgb H, and Hgb M. In normal adults, only HbA and HbA2 are present at significant levels. Small amounts of HbF (which is the major Hb present in the fetus) may be present, but they are of no consequence unless levels are more than 2% of the total.
HbS is an abnormal form of hemoglobin associated with sickle cell anemia. HbS forms clumps in the presence of low oxygen, causing the red blood cells to take on a crescent or sickle shape. These misformed cells then break down, or can block small blood vessels.
HbC is an abnormal form of hemoglobin associated with hemolytic anemia. The symptoms are much milder than they are in sickle cell anemia.
Other, less common, abnormal Hb molecules cause anemias of various degrees of severity.
|
