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Cerebrospinal Fluid (CSF) White Blood Cell Count with Differential (Qualitative)

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

This test examines the types and proportions of white blood cells in your cerebrospinal fluid (CSF), which surrounds your brain and spinal cord. It helps identify infections, inflammation, or other conditions affecting the central nervous system.

Quick summary

["This qualitative test assesses CSF white blood cell composition to guide diagnosis of neurological issues."]

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

Key facts at a glance

LOINC
64087-0
Short code
ISCN band level CVS Ql
Synonyms
ISCN band level CVS Ql
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
molgen
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

Why This Test Is Done

Your doctor may order this test if you have symptoms like headaches, neck stiffness, fever, confusion, or neurological problems. It’s often used to investigate conditions such as meningitis, encephalitis, or other infections/inflammatory diseases of the brain or spinal cord.

What to Expect Before the Test

You’ll typically undergo a lumbar puncture (spinal tap), where a needle is inserted into your lower back to collect CSF. The procedure is usually quick and may cause mild discomfort. You may be asked to lie still for a short time afterward.

What the Test Results Mean

Results show the types of white blood cells (e.g., neutrophils, lymphocytes, monocytes) present in your CSF. Elevated counts of certain cells can indicate specific conditions, such as bacterial infections (neutrophils), viral infections (lymphocytes), or autoimmune diseases.

Common Conditions Linked to Abnormal Results

High numbers of neutrophils may suggest bacterial meningitis or abscesses. Increased lymphocytes could indicate viral meningitis, encephalitis, or demyelinating diseases. Monocytes may appear in chronic infections or inflammatory conditions.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Clinical Significance: How Results Guide Treatment

Short name

CSF WBC Qualitative

Frequently asked questions

What does a positive or abnormal result mean?
An abnormal result (e.g., unusual cell types or counts) often prompts further testing, such as cultures, imaging, or additional CSF analyses to pinpoint the underlying cause. Your doctor will interpret results in the context of your symptoms and medical history.
How long does it take to get results?
Qualitative results are typically available immediately after the lumbar puncture, though some labs may take a few hours to confirm findings. Follow-up testing may delay final diagnoses.
Can I eat or drink before this test?
You can eat and drink normally before the test, as it doesn’t require fasting. However, inform your doctor about any medications or supplements you’re taking, as they may affect results.
  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