Skip to content

Cerebrospinal Fluid (CSF) Protein by Nephelometry

Published: August 9, 2026Updated: August 16, 2026

This test measures the total protein content in your cerebrospinal fluid, which is the clear fluid surrounding your brain and spinal cord. It helps assess conditions affecting the central nervous system.

Quick summary

["Measuring CSF protein can help diagnose or monitor neurological conditions."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
29361-3
Short code
Deprecated S pneumB Ag CSF Ql
Synonyms
Deprecated S pneumB Ag CSF Ql
Category
coagulation
Sample
csf
Container
Sterile tube
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Specimen volume
1-2 mL
Stability
Immediate analysis required, Refrigerated: 1h
Hemolysis max
200
TAT
4–24 hours
Order
routine

Why This Test Is Done

Your healthcare provider may order this test if you have symptoms like headaches, neck stiffness, confusion, or neurological issues. It can also be part of a broader evaluation for conditions such as infections, inflammation, or tumors in the brain or spinal cord.

What to Expect During the Test

A small amount of CSF is collected through a procedure called a lumbar puncture (spinal tap). You’ll lie on your side, and a needle is gently inserted into your lower back. The fluid is then sent to the lab for testing.

Possible Results and Interpretation

CSF protein levels can vary based on health, age, and other factors. High levels may suggest conditions like meningitis, multiple sclerosis, or other inflammatory or infectious processes. Low levels are less common but may occur in certain neurological disorders.

Common Conditions Affecting Results

Elevated CSF protein is often seen in conditions that cause inflammation, infection, or breakdown of the blood-brain barrier. Conditions like multiple sclerosis, encephalitis, or certain types of brain tumors can also lead to abnormal protein levels.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Clinical Significance

Short name

CSF Protein

Frequently asked questions

What causes elevated CSF protein levels?
Elevated CSF protein can result from infections (such as bacterial or viral meningitis), autoimmune diseases (like multiple sclerosis), tumors, or other neurological conditions that affect the brain’s protective barrier or cause inflammation.
How soon will I get my results?
Results from this test are typically available within 1 to 3 business days, depending on your lab’s processing time. Your healthcare provider will discuss the results with you during your follow-up visit.
Can I eat or drink before this test?
You can eat and drink normally before the test, as it does not require fasting. However, inform your provider if you’re taking any medications that might affect CSF composition.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy