Immunoelectrophoresis - urine

Definition

Urine immunoelectrophoresis is a test that tells whether or not you have immunoglobulins in the urine.

Immunoglobulins are proteins that function as antibodies. The proteins can be abnormal.

Alternative Names

Immunoglobulin electrophoresis - urine; Gammaglobulin electrophoresis - urine; Urine immunoglobulin electrophoresis; IEP - urine

How the test is performed

Collect a "clean-catch" (midstream) urine sample. To obtain a clean-catch sample, men or boys should wipe clean the head of the penis. Women or girls need to wash the area between the labia (lips of the vagina) with soapy water and rinse well.

As you start to urinate, allow a small amount to fall into the toilet bowl. This clears the urethra -- the tube that carries urine from the bladder and opens to the outside. Then, in a clean container, catch about 1 - 2 ounces of urine. Remove the container from the urine stream. Give the container to the health care provider or assistant.

In an infant, thoroughly wash the area around the opening of the urethra. Open a urine collection bag (a plastic bag with an adhesive paper on one end), and place it on your infant. For males, the entire penis can be placed in the bag and the adhesive attached to the skin. For females, the bag is placed over the labia. Place a diaper over the infant (bag and all).

Check your baby frequently, and remove the bag after the infant has urinated into it. For active infants, this procedure may take a couple of attempts. Lively infants can displace the bag, making it difficult to get the specimen. Drain the urine into a container for transport back to the health care provider.

The laboratory technician uses electrical charges to separate and identify various immunoglobulins in the urine.

How to prepare for the test

Your health care provider may recommend that you collect the first morning urine, which is the most concentrated.

If you are taking the collection from an infant, you may need a couple of extra collection bags.

How the test will feel

The test involves only normal urination, and there is no discomfort.

Why the test is performed

This test is used to measure the amounts of various immunoglobulins in urine. Most often, it is used as a screening test. It can be used in people who have protein in the urine, when urine protein electrophoresis indicates a large amount of globulins.

Normal Values

Normally there is no, or only a small amount, of protein in the urine. When there is protein in the urine, it normally consists of mainly albumin.

Normal value ranges may vary slightly among different laboratories. Talk to your doctor about the meaning of your specific test results.

What abnormal results mean

Immunoglobulin (antibodies) in the urine can result from:

• Kidney disorders such as IgA nephropathy or IgM nephropathy
• Multiple myeloma (a form of cancer)

See also: Immunoelectrophoresis - serum

In some diseases that cause abnormal cell growth (for example, multiple myeloma or chronic lymphocytic leukemia), one type of immunoglobulin -- a monoclonal immunoglobulin -- is produced. This can be found by immunoelectrophoresis. Some people have monoclonal immunoglobulins, but they do not have such diseases.

Waldenstrom's macroglobulinemia is another condition under which the test may be performed.

References

McPherson RA and Pincus MR. Henry's Clinical Diagnosis and Management by Laboratory Methods. 21st ed. Philadelphia, Pa: WB Saunders; 2007:843-845.

Hoffman R, Benz Jr. EJ, Shattil SJ, et al., eds. Hematology: Basic Principles and Practice. 4th ed. Philadelphia, Pa: Churchill Livingston; 2005:727-733.