Version July 2025
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What is urine protein electrophoresis? —
Urine protein electrophoresis, or "UPEP," is a test to measure the level of certain proteins in urine.
Protein is not normally found in urine. UPEP can give doctors more information and help them figure out the cause.
For UPEP, you collect all your urine over a 24-hour period. Then, an electrical current is used on a sample of the urine to separate several different types of protein. This measures the amount of each of these protein types.
What is immunofixation? —
This is a test that can be used along with UPEP to learn more about the proteins in urine.
If the UPEP pattern shows unexpectedly high levels of 1 type of protein, immunofixation can give doctors more information and help them figure out the cause. It can show if the high level is due to many copies of the same protein (called "monoclonal" proteins) or many different proteins (called "polyclonal" proteins). It can also tell the doctor more about the type of protein involved, and can sometimes find proteins that are missed by the UPEP.
Why might I need these tests? —
Doctors mostly use these tests to:
●Figure out why there is protein in urine
●Learn more if a blood test finds a monoclonal protein
●See how the protein levels in urine change over time
●Check for certain types of cancer, including multiple myeloma, Waldenström macroglobulinemia, and AL amyloidosis
●Monitor how treatment is working for these types of cancer
How do I collect my urine? —
You need to collect all the urine your body produces over a 24-hour period. To do this:
●Urinate as soon as you wake up on the first morning. Do not collect this urine. You can flush it down the toilet like usual. Write down the exact time this happens. This is the start of your 24-hour collection period.
●Collect the rest of your urine for the next 24 hours. During this time, it is important to collect all your urine, even if it is a very small amount.
●Use the bottle your doctor or nurse gave you to collect your urine. If you need to, you can urinate into a smaller cup or a special pan, and then empty that into the large collection bottle. Store the bottle in the refrigerator until you bring it to your doctor.
What do my results mean? —
Your doctor or nurse will tell you when to expect your results, and will contact you with the results. Or if you use an online "patient portal," you might get an alert there when your results are ready.
If your UPEP or immunofixation test shows any abnormal results, your doctor or nurse will talk to you about what to do next. They might need to do more tests to figure out the cause.
If you do have a health problem, your doctor will work with you to come up with a treatment plan.
Patient education: Serum protein electrophoresis and immunofixation (The Basics)
Patient education: 24-hour urine collection (The Basics)
Patient education: Multiple myeloma (The Basics)
Patient education: Waldenström macroglobulinemia (The Basics)
Patient education: AL amyloidosis (The Basics)
Patient education: Collection of a 24-hour urine specimen (Beyond the Basics)
Patient education: Protein in the urine (proteinuria) (Beyond the Basics)
Patient education: Multiple myeloma symptoms, diagnosis, and staging (Beyond the Basics)
Patient education: Multiple myeloma treatment (Beyond the Basics)
