CSF myelin basic protein
Definition
CSF myelin basic protein is a test to measure the level of myelin basic protein (MBP) in the cerebrospinal fluid (CSF), the clear liquid that surrounds the brain and spinal cord.
MBP is found in the material that covers your nerves.
A sample of CSF is needed. The most common way to collect this sample is with a lumbar puncture, also called a spinal tap. See the article on lumbar puncture for details about this procedure.
Other methods of collecting CSF are rarely used, but may be recommended in some cases. They include:
- Cisternal puncture
- Ventricular puncture
- Removing CSF from a tube already in place in the CSF, such as a shunt or ventricular drain
After the sample is taken, it is sent to a laboratory for evaluation.
Why the Test is Performed
This test is done to see if myelin, the substance covering your nerves, is breaking down. Myelin breakdown is called demyelination. Multiple sclerosis is the most common cause for this, but other causes may include:
- Bleeding of the central nervous system
- Central nervous system trauma
- Certain brain diseases (encephalopathies)
- Infection of the central nervous system
- Stroke
How the Test is Performed
See: Lumbar puncture.
How the Test Will Feel
For detailed information, see the article on lumbar puncture.
Risks
For information on the risks of spinal tap, see: Lumbar puncture and CSF collection.
Normal Results
In general there should be less than 4 ng/mL of myelin basic protein in the CSF.
Note: ng/mL = nanogram per milliliter
Note: 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
Myelin basic protein levels between 4 and 8 ng/mL may be a sign of a chronic breakdown of myelin, or recovery from an acute episode of myelin breakdown.
If the myelin basic protein levels are greater than 9 ng/mL, myelin is actively breaking down.
Reviewed By: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; Daniel B. Hoch, PhD, MD, Assistant Professor of Neurology, Harvard Medical School, Department of Neurology, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
