Cerebrospinal fluid (CSF) is the liquid that protects and cushions your brain and spinal cord.

An oligoclonal band is a protein called an immunoglobulin. The CSF oligoclonal band screen looks for these bands in your CSF. Their presence suggests inflammation of the central nervous system due to infection or another disease. If similar bands aren’t present in your blood, you may have multiple sclerosis (MS).

The test is also known as CSF oligoclonal banding or CSF immunofixation.

Doctors can use this screen to help them diagnose MS. They can also use it to diagnose other inflammatory conditions and neurological diseases.

A normal result is no bands or just one band. The presence of multiple bands indicates that something is wrong. This is particularly true if they don’t find similar bands in your blood.

This test is usually ordered if your doctor thinks you may have MS. According to Mayo Medical Laboratories, this screen is positive in 70 to 80 percent of MS patients.

A positive test might also indicate that you have:

  • neurosyphilis
  • encephalitis
  • meningitis
  • Lyme disease

Your doctor will need to know if you:

  • are taking any blood thinners
  • have a history of back or spine problems
  • have any neurological illnesses or conditions
  • have an infection or rash on your back

As always, give your doctor complete information on what medications you take. Make certain to include both prescription and over-the-counter medicines.

If your work is strenuous and might involve your back, tell your doctor. You may need to arrange to take the day of your test off. You should expect to rest for at least an hour after your test.

This test involves a lumbar puncture, or spinal tap, which takes place at a hospital or clinic. The following steps take place during a lumber puncture:

  1. You’ll need to change into a hospital gown with the back open. This gown gives the person conducting the test easy access to your spine.
  2. They’ll ask you to turn on your side and expose your back. You may also sit up and bend over.
  3. The person conducting the test will clean your back with antiseptic.
  4. Next, they’ll apply a local anesthetic. After a few moments, it will begin working. The anesthetic will reduce or eliminate the pain of needle insertion.
  5. They’ll ask you to hold still, and they’ll insert a hollow needle into your lower spine.
  6. They’ll withdraw a small amount of CSF.
  7. Then, they’ll remove the needle.
  8. The person conducting the test will clean and cover the puncture.
  9. They’ll send the CSF to a laboratory for analysis.

You can expect to rest for an hour or two after your test. Your doctor may suggest you take a mild pain reliever.

Lumbar puncture is widely used and considered safe. However, medical risks exist, including:

  • bleeding into the spine
  • an allergic reaction to the anesthetic
  • an infection
  • damage to the spinal cord if you move
  • brain herniation if a brain mass is present

People usually have discomfort during and shortly after the test.

Some people have a headache after a lumbar puncture. This should go away within 24 hours. Let your doctor know if it doesn’t.

Your test results should be ready in a couple of days. Your doctor will read them and discuss the next steps.

The presence of no oligoclonal bands or one band is normal. The presence of more than one band is an indicator of illness. In this case, further tests will be necessary to determine the cause of any disease.