Immunofixation - urine

How the Test is Performed:
Child or adult:
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 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 of contaminants). Then, in a clean container, catch about 1 to 2 ounces of urine and remove the container from the urine stream. Give the container to the health care provider or assistant.

Infant:
Thoroughly wash the area around 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, causing an inability to obtain the specimen. The urine is drained into a container for transport back to the health care provider.

Immunofixation is a laboratory technique that is used to enhance the results of standard protein electrophoresis . With protein electrophoresis, the urine is placed on specially treated paper and exposed to an electric current. The various proteins migrate (move on the paper) to form bands that indicate the relative proportion of each protein fraction. Immunoglobulins ( antibodies ) appear as a "gamma" band. Immunofixation is a technique to separate this "gamma" band and identify the individual immunoglobulins. It is similar to immunoelectrophoresis but may give more rapid results and is slightly more sensitive.

How to Prepare:
No special preparation is necessary for this test, but if the collection is being taken from an infant, a couple of extra collection bags may be necessary.

How it Feels:
The test involves only normal urination, and there is no discomfort.

Risks:
There are no risks.

Why this Test is Performed:
The primary use of immunofixation is the identification and monitoring of monoclonal proteins (that is, IgG , IgM , IgA , lambda light chain, and kappa light chain), including those that are present in multiple myeloma and Waldenstrom's macroglobulinemia .

Normal Values:
No presence of monoclonal immunoglobulins is normal.

Abnormal Results:
Usually, abnormal results indicate immune system disorders including multiple myeloma and Waldenstrom's macroglobulinemia .

Sometimes monoclonal immunoglobulins are present but no evidence can be found of malignancy .

Cost:
The estimated cost is $90.

Special Considerations:
Not applicable.


This is an illustration of the female urinary tract. The female and male urinary tracts are relatively the same except for the length of the urethra. The positioning in the body and relative size of the organs are also demonstrated.



This is an illustration of the male urinary tract. The female and male urinary tract are relatively the same except for the length of the urethra. The positioning and relative size of the organs are also shown.