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Cerebrospinal fluid cell count (with differential analysis)

Published: August 9, 2026Updated: August 15, 2026

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

Quick summary

["Assesses white blood cell activity in CSF to guide diagnosis of neurological issues."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 15, 2026Editorial policy

Key facts at a glance

LOINC
14965-8
Short code
CD2ABN
Synonyms
CD2 Abn Bld Cells NFr
Category
chemistry
Sample
whole-blood
Container
Lavender-top (EDTA) or sodium heparin green-top tube for flow cytometry; sodium heparin is preferred for optimal lymphocyte viability in delayed shipping.
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
Flow cytometry immunophenotyping
CPT
88184
SNOMED
395146009
Specimen volume
3-5 mL whole blood (minimum 1 mL for pediatric patients)
Stability
Ambient: 24 hours; Refrigerated (2-8°C): 48 hours. Specimen should be processed within 24 hours of collection for optimal lymphocyte viability and antigen integrity. Do not freeze.
Hemolysis max
100
Lipemia max
500
TAT
24–72 hours
Order
routine

What Is a CSF Cell Count Used For?

A CSF cell count helps doctors determine if there’s an abnormal number of white blood cells in your spinal fluid. High counts may suggest infections (like meningitis), autoimmune diseases, or other inflammatory conditions. Low counts could indicate bleeding, certain neurological disorders, or lack of infection.

How Is This Test Performed?

A small amount of CSF is collected through a procedure called a lumbar puncture (spinal tap). The fluid is sent to the lab, where it’s examined under a microscope to count and identify different types of white blood cells (neutrophils, lymphocytes, monocytes, etc.).

When Might You Need This Test?

Your doctor may order this test if you have symptoms like severe headaches, neck stiffness, fever, confusion, or neurological problems (e.g., vision changes, numbness). It’s also used to monitor conditions like multiple sclerosis, encephalitis, or subarachnoid hemorrhage.

What Are Common Results and Next Steps?

Results are typically reported as a total cell count (e.g., cells per microliter) and a breakdown of cell types. Elevated counts (especially lymphocytes) may point to infection or inflammation. Elevated neutrophils could indicate bacterial infection. Follow-up may include additional imaging, cultures, or treatments based on findings.

Reference range

Abnormal cells are typically reported as 'none detected' or 'present' on a qualitative basis. Quantitative expression of CD2 on abnormal lymphocytes should be interpreted in conjunction with the complete immunophenotyping panel and morphological findings.N/A

Specimen: whole-blood

No fasting required. Patient should be well-hydrated. For serial monitoring, specimen collection should occur at the same time of day to minimize diurnal variation. Avoid recent immunosuppressive therapy if possible, or document recent treatment, as it may affect lymphocyte subset distribution.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

CSF Cell Count with Differential

Frequently asked questions

Why might my CSF cell count be higher than expected?
Higher-than-normal counts could be due to infections (like viral or bacterial meningitis), autoimmune diseases (e.g., multiple sclerosis), or inflammatory conditions. Your doctor will review symptoms and may order additional tests to determine the cause.
What should I do if my CSF cell count is abnormal?
If your results are abnormal, your doctor will discuss next steps, which may include further imaging, cultures, or treatments (e.g., antibiotics for infections). Follow their guidance closely and report any worsening symptoms immediately.
Can lifestyle changes affect my CSF cell count results?
While lifestyle factors like stress or diet may influence overall health, they rarely directly affect CSF cell counts. Your test results depend on the underlying condition being evaluated, so focus on following your doctor’s recommendations for diagnosis and treatment.
  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 15, 2026. · Read our editorial policy