Hemoglobin Electrophoresis
Hemoglobin ElectrophoresisSkip to the navigationTest OverviewA hemoglobin electrophoresis test is a blood
test done to check the different types of
hemoglobin in the blood. Hemoglobin is the substance
in red blood cells that carries oxygen. The most common types of
normal hemoglobin are: - Hemoglobin A. This
is the most common type of hemoglobin found normally in adults. Some diseases,
such as severe forms of
thalassemia, may cause hemoglobin A levels to be low
and hemoglobin F levels to be high.
- Hemoglobin F (fetal hemoglobin). This type is normally found in
fetuses and newborn babies. Hemoglobin F is replaced
by hemoglobin A (adult hemoglobin) shortly after birth; only very small amounts
of hemoglobin F are made after birth. Some diseases, such as
sickle cell disease,
aplastic anemia, and
leukemia, have abnormal types of hemoglobin and higher
amounts of hemoglobin F.
- Hemoglobin A2. This is a normal type of hemoglobin found in small amounts in
adults.
There are more than 350 types of abnormal hemoglobin.footnote 1 The most common are: - Hemoglobin S. This type
of hemoglobin is present in sickle cell disease.
- Hemoglobin C. This type of hemoglobin does not carry oxygen well.
- Hemoglobin E. This type
of hemoglobin is found in people of Southeast Asian descent.
- Hemoglobin D. This type of hemoglobin is present in some sickle cell disorders.
Hemoglobin S and hemoglobin C are the most common types of
abnormal hemoglobin that may be found by an electrophoresis test. Electrophoresis uses an electrical current to separate normal and
abnormal types of hemoglobin in the blood. Hemoglobin types have different
electrical charges and move at different speeds. The amount of each hemoglobin
type in the current is measured. An abnormal amount of normal
hemoglobin or an abnormal type of hemoglobin in the blood may mean that a
disease is present. Abnormal hemoglobin types may be present without any other
symptoms, may cause mild diseases that do not have symptoms, or cause diseases
that can be life-threatening. For example, hemoglobin S is found in sickle cell
disease, which is a serious abnormality of the blood and causes serious
problems. Why It Is DoneHemoglobin electrophoresis is done
to: - Find each type of hemoglobin in the blood. This
can be used to diagnose certain types of
anemia (such as thalassemia).
- Check
treatment for diseases that have abnormal types of hemoglobin in the
blood.
- Help couples find out how likely they are to have a child
with certain forms of anemia that can be passed from a parent to a child
(inherited).
How It Is DoneThe health professional drawing blood
will: - Wrap an elastic band around your upper arm to
stop the flow of blood. This makes the veins below the band larger so it is
easier to put a needle into the vein.
- Clean the needle site with
alcohol.
- Put the needle into the vein. More than one needle stick
may be needed.
- Attach a tube to the needle to fill it with
blood.
- Remove the band from your arm when enough blood is
collected.
- Put a gauze pad or cotton ball over the needle site as
the needle is removed.
- Put pressure on the site and then put on a
bandage.
How It FeelsThe blood sample is taken from a vein in
your arm. An elastic band is wrapped around your upper arm. It may feel tight.
You may feel nothing at all from the needle, or you may feel a quick sting or
pinch. RisksThere is very little chance of a problem from
having a blood sample taken from a vein. - You may get a small bruise at the site. You can
lower the chance of bruising by keeping pressure on the site for several
minutes.
- In rare cases, the vein may become swollen after the blood
sample is taken. This problem is called phlebitis. A warm compress can be used
several times a day to treat this.
ResultsA hemoglobin electrophoresis test is a
blood test done to check the different types of
hemoglobin in the blood. Results are ready in several
days. NormalThe normal values listed here-called a reference range-are just a guide. These ranges vary from lab to lab, and your lab may have a different range for what's normal. Your lab report should contain the range your lab uses. Also, your doctor will evaluate your results based on your health and other factors. This means that a value that falls outside the normal values listed here may still be normal for you or your lab. Hemoglobin electrophoresisfootnote 1Hemoglobin
A1: | 96.5%-98.5% of total
hemoglobin or 0.96-0.985 mass fraction |
|---|
Hemoglobin
A2: | 1.5%-3.5% of total
hemoglobin or 0.015-0.035 mass fraction |
|---|
Hemoglobin
F: | 0%-1% of total
hemoglobin or 0-0.01 mass fraction |
|---|
Abnormal
hemoglobin types: | None |
|---|
High and low values- Higher-than-normal amounts of both hemoglobin
A2 and
hemoglobin F may mean a mild form of
thalassemia is present. A very low level of hemoglobin
A and a high level of hemoglobin F may mean a more severe form of thalassemia.
High levels of hemoglobin F may be seen in a rare condition called hereditary
persistence of fetal hemoglobin.
- Hemoglobin S in moderate amounts
can mean that
sickle cell trait is present. Hemoglobin S in high
amounts means
sickle cell disease.
- Hemoglobin C in low
amounts can mean that
hemoglobin C trait is present. Hemoglobin C in high
amounts means hemoglobin C disease, which causes anemia and an enlarged
spleen.
- Hemoglobin types S and C mean hemoglobin S-C disease, which
causes a mild or moderate form of sickle cell disease.
- Hemoglobin E
in low amounts means the presence of
hemoglobin E trait. Hemoglobin E in high amounts means
hemoglobin E disease, which causes anemia and smaller-than-normal red blood
cells.
- Hemoglobin types other than S, C, D, and E are rare. But
over 350 types of abnormal hemoglobin have been found.footnote 1
What Affects the TestReasons you may not be able to
have the test or why the results may not be helpful include: - Having a blood transfusion in the past 3
months.
- Having
iron deficiency anemia. This can cause falsely low
results for hemoglobin A2.
What To Think AboutIf you are planning to have
children and are found to have abnormal types of hemoglobin in your blood, you
might consider
genetic counseling. This can help you and your partner
see how likely you are to have children with certain inherited forms of anemia
(such as sickle cell disease or thalassemia). ReferencesCitations- Fischbach FT, Dunning MB III, eds. (2009). Manual of Laboratory and Diagnostic Tests, 8th ed. Philadelphia: Lippincott Williams and Wilkins.
Other Works Consulted- Chernecky CC, Berger BJ (2008). Laboratory Tests and Diagnostic Procedures, 5th ed. St. Louis: Saunders.
- Fischbach FT, Dunning MB III, eds. (2009). Manual of Laboratory and Diagnostic Tests, 8th ed. Philadelphia: Lippincott Williams and Wilkins.
- Pagana KD, Pagana TJ (2010). Mosby's Manual of Diagnostic and Laboratory Tests, 4th ed. St. Louis: Mosby Elsevier.
CreditsByHealthwise Staff
Primary Medical ReviewerE. Gregory Thompson, MD - Internal Medicine
Adam Husney, MD - Family Medicine
Specialist Medical ReviewerJoseph O'Donnell, MD - Hematology, Oncology Current as ofOctober 14, 2016 Current as of:
October 14, 2016 Fischbach FT, Dunning MB III, eds. (2009). Manual of Laboratory and Diagnostic Tests, 8th ed. Philadelphia: Lippincott Williams and Wilkins. Last modified on: 8 September 2017
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