Blast Cell Count, Cerebrospinal Fluid
This test examines cerebrospinal fluid for blast cells, which are immature white blood cells that may suggest leukemia or lymphoma involving the nervous system.
["Detecting blast cells in cerebrospinal fluid may be an important sign of blood cancer involving the nervous system."]
Key facts at a glance
- LOINC
- 26447-3
- Short code
- Blasts NFr CSF
- Synonyms
- Blasts NFr CSF
- Category
- liver
- Sample
- csf
- Container
- Sterile tube
- Units
- N/A
- Ref low
- 10
- Ref high
- 40
- Critical range
- — – 500 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 84484
- SNOMED
- 302774002
- Specimen volume
- 1-2 mL
- Stability
- Immediate analysis required, Refrigerated: 1h
- Hemolysis max
- 200
- TAT
- 4–24 hours
- Order
- routine
What is this test?
A cerebrospinal fluid blast cell count examines the fluid surrounding the brain and spinal cord for blast cells. Blasts are immature white blood cells that normally remain in the bone marrow while they develop.
Why might I need this test?
This test may be used when a person has leukemia or lymphoma and there is concern that the disease has spread to the nervous system. It may also be part of an evaluation for unexplained neurologic symptoms.
How is the test performed?
A sample of cerebrospinal fluid is collected, usually through a lumbar puncture, and examined by laboratory specialists. The laboratory may use microscopic review and, when appropriate, flow cytometry to identify and count blast cells.
How do I prepare for the test?
Cerebrospinal fluid is usually collected by a clinician, so your medical team will explain the procedure and any preparation instructions. You may be asked to lie still in a specific position while the sample is collected.
Reference range
Adult: 10-40 U/LN/A
No special preparation required. Avoid fatty meals before the test if possible.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Finding blast cells in cerebrospinal fluid can be a sign of acute leukemia or lymphoma involving the nervous system. Results must be interpreted with the blood findings, symptoms, imaging, and other laboratory tests because abnormal-appearing cells can sometimes have other causes.
Short name
CSF Blast Cell Count
Frequently asked questions
Does finding blast cells in cerebrospinal fluid confirm cancer?
Is a lumbar puncture painful?
Can this test be performed on a sample collected earlier?
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