Eosinophil count in cerebrospinal fluid (CSF) by mass concentration
This test measures the number of eosinophils, a type of white blood cell, in your cerebrospinal fluid (CSF). Eosinophils are involved in fighting certain types of infections and allergic reactions.
["Eosinophils in CSF can help diagnose conditions affecting the brain or spinal cord."]
Key facts at a glance
- LOINC
- 31824-6
- Short code
- E coli K1 Ag CSF Ql
- Synonyms
- E coli K1 Ag CSF Ql
- Category
- chemistry
- 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 is this test done?
Your healthcare provider may order this test if you have symptoms like severe headaches, neck stiffness, confusion, or neurological issues that suggest conditions such as meningitis, encephalitis, or certain types of brain tumors. It can also be used to monitor responses to treatment for these conditions.
What does the test involve?
A small amount of CSF is collected through a procedure called a lumbar puncture (spinal tap). The fluid is then analyzed in the lab to count eosinophils.
What might abnormal results mean?
Elevated eosinophil counts in CSF may indicate conditions such as eosinophilic meningitis, certain parasitic infections, or allergic reactions involving the central nervous system. Lower-than-expected counts might suggest other infections or inflammatory conditions.
How is the test performed?
The test involves sending the CSF sample to a lab where it is examined under a microscope to count eosinophils. The method used is typically a microscopic cell count, which provides a qualitative or semi-quantitative assessment of cell types present.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Eosinophil counts in CSF are crucial for diagnosing and managing conditions that affect the central nervous system. High levels can point toward specific infections or allergic responses, guiding treatment decisions such as antibiotic therapy or targeted immune interventions. Regular monitoring of eosinophil levels can also help assess the effectiveness of ongoing treatments.
Short name
CSF Eosinophil Count
Frequently asked questions
What does a high eosinophil count in CSF mean?
How long does it take to get results?
Is there any preparation needed before the 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 16, 2026. · Read our editorial policy