Cerebrospinal Fluid (CSF) Protein by Manual Qualitative Analysis (Bromocresol Green)
This test checks the protein levels in your cerebrospinal fluid (CSF), which is the fluid surrounding your brain and spinal cord. It may be used to evaluate conditions affecting the central nervous system.
["Assesses protein presence in CSF to help diagnose or monitor neurological conditions."]
Key facts at a glance
- LOINC
- 46091-5
- Short code
- RBC tube3 # CSF Manual
- Synonyms
- RBC tube3 # CSF Manual
- Category
- chemistry
- Sample
- csf
- Container
- Sterile tube
- Units
- N/A
- Ref low
- 4.2
- Ref high
- 5.9
- Critical range
- 2 N/A – 7 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- manual-count
- CPT
- 85041
- SNOMED
- 900000000000003001
- 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 doctor may order this test to investigate symptoms such as headaches, neurological issues, infections, or inflammation in the brain or spinal cord. It can also help diagnose conditions like meningitis, multiple sclerosis, or other spinal fluid abnormalities.
What to Expect Before the Test
No special preparation is typically needed. You may receive a spinal tap (lumbar puncture) where a small amount of CSF is collected via a needle inserted into your lower back. The test involves a manual qualitative method using bromocresol green dye to detect protein presence.
What the Test Results Mean
Results are qualitative (positive or negative) rather than quantitative. A positive result indicates the presence of abnormal protein levels, which may suggest conditions like Guillain-Barré syndrome, multiple sclerosis, or other inflammatory or infectious processes in the CSF.
Common Conditions Monitored
This test helps identify or confirm conditions affecting the central nervous system, such as infections (e.g., bacterial or viral meningitis), autoimmune diseases (e.g., multiple sclerosis), or tumors. Elevated protein levels can also indicate increased blood-brain barrier permeability.
Reference range
Adult males: 4.2-5.9; Females: 3.8-5.1 x 10^12/LN/A
No special preparation required. Stay well hydrated.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical significance: Elevated protein in CSF is often associated with inflammatory, infectious, or neoplastic processes. While this test does not provide exact protein concentration, it serves as a screening tool to prompt further investigation (e.g., CSF culture, MRI, or additional lab tests) based on clinical context.
Short name
CSF Protein Qualitative Test
Frequently asked questions
What does a positive result mean?
How long does it take to get results?
Can I eat or drink before this test?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
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.
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 17, 2026. · Read our editorial policy