Immunoelectrophoresis - serum
Definition
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Serum immunoelectrophoresis is a test that measures immunoglobulins in the blood. Immunoglobulins are proteins that function as antibodies. There are various types of immunoglobulins. Some some can be abnormal. If you do have these abnormal proteins, this test can also help identify their specific type.
Alternative Names
IEP - serum; Immunoglobulin electrophoresis - serum; Gammaglobulin electrophoresis; Serum immunoglobulin electrophoresisWhy the Test is Performed
This test is performed to assess the clonality (monoclonal or polyclonal, meaning derived from one group of cells producing them) of immunoglobulins.
How the Test is Performed
Blood is typically drawn from a vein, usually from the inside of the elbow or the back of the hand. The site is cleaned with germ-killing medicine (antiseptic). The health care provider wraps an elastic band around the upper arm to apply pressure to the area and make the vein swell with blood.
Next, the health care provider gently inserts a needle into the vein. The blood collects into an airtight vial or tube attached to the needle. The elastic band is removed from your arm.
Once the blood has been collected, the needle is removed, and the puncture site is covered to stop any bleeding.
In infants or young children, a sharp tool called a lancet may be used to puncture the skin and make it bleed. The blood collects into a small glass tube called a pipette, or onto a slide or test strip. A bandage may be placed over the area if there is any bleeding.
How the Test Will Feel
When the needle is inserted to draw blood, you may feel moderate pain, or only a prick or stinging sensation. Afterward, there may be some throbbing.
Risks
- Excessive bleeding
- Fainting or feeling lightheaded
- Hematoma (blood accumulating under the skin)
- Infection (a slight risk any time the skin is broken)
Veins and arteries vary in size from one patient to another and from one side of the body to the other. Obtaining a blood sample from some people may be more difficult than from others.
What Abnormal Results Mean
In some malignant disorders (most often multiple myeloma or chronic lymphocytic leukemia) a single clone of lymphocytes produces one type of protein -- a monoclonal immunoglobulin. This is identifiable as monoclonal (all the same type) by immunoelectrophoresis. Some people have monoclonal immunoglobulins, but do not have a malignant disorder.
Reviewed By: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; and James R. Mason, MD, Oncologist, Director, Blood and Marrow Transplantation Program and Stem Cell Processing Lab, Scripps Clinic, Torrey Pines, California. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
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