Cerebrospinal Fluid (CSF) Test — Analyte Not Identified

What is this test?

Cerebrospinal fluid, or CSF, is produced around the brain and spinal cord. Testing CSF can help clinicians investigate neurological symptoms or illness affecting the central nervous system. The abbreviated code clearly identifies CSF as the specimen, but it does not reliably identify the specific analyte being measured.

Why might I need this test?

CSF testing may be ordered for symptoms such as severe headache, fever, stiff neck, confusion, weakness, seizures, or other changes in nervous-system function. Depending on the exact test, results may help evaluate infection, inflammation, bleeding, or other causes of neurological symptoms.

How is the test performed?

A clinician or trained specialist usually obtains CSF with a lumbar puncture, also called a spinal tap. A needle is inserted into the lower back, and a small amount of fluid is collected for laboratory analysis. The laboratory then performs the specific analysis listed on the order.

How do I prepare for the test?

No food or drink restriction is usually required for a lumbar puncture. Tell your clinician about blood-thinning medicines, medicines or conditions affecting the nervous system, and any prior spinal procedures. You will normally be asked to lie on your side or curl forward, and a local anesthetic is generally used to reduce discomfort.