Cerebrospinal fluid immunoglobulin free light chain profile (total and individual chains)
This test measures free light chains (small protein fragments) produced by plasma cells in your cerebrospinal fluid (CSF). These fragments can help diagnose conditions like multiple myeloma, lymphoma, or other immune system disorders.
["This test helps identify abnormal protein fragments in your brain’s fluid that may signal serious health concerns."]
Key facts at a glance
- LOINC
- 49193-6
- Short code
- CALENC
- Synonyms
- CEV IgM Titr CSF
- Category
- chemistry
- Sample
- csf
- Container
- Sterile CSF collection tube (polypropylene); tube #3 or #4 typically recommended for microbiology/serology to minimize blood contamination
- Units
- N/A
- Ref low
- 0
- Ref high
- 1
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- Enzyme Immunoassay (EIA) or Immunofluorescence Assay (IFA) for detection of California encephalitis virus IgM antibodies
- CPT
- 86651
- SNOMED
- 122496003
- Specimen volume
- 1-2 mL of cerebrospinal fluid
- Stability
- Refrigerated (2-8°C): 7 days; Frozen (-20°C or below): 30 days; Avoid repeated freeze-thaw cycles
- Hemolysis max
- 200
- TAT
- 24–168 hours
- Order
- routine
Why This Test Is Done
Your doctor may order this test if you have symptoms like headaches, neurological problems, or a suspected immune-related condition. It’s often used alongside other tests to check for conditions affecting the brain, spinal cord, or blood cells.
What to Expect Before the Test
You’ll have a small needle inserted into your back to collect a sample of cerebrospinal fluid (CSF) through a procedure called a lumbar puncture (spinal tap). The fluid is then analyzed for free light chains.
What the Test Results Mean
High levels of free light chains in CSF can indicate conditions like multiple myeloma, lymphoma, or other plasma cell disorders. Normal results suggest no significant abnormalities in these fragments.
Common Conditions This Test Helps Diagnose
This test is particularly useful for diagnosing multiple myeloma (a cancer of plasma cells), primary central nervous system lymphoma, or other immune-related diseases affecting the CSF.
Reference range
Titer <1:2 (Negative). A titer of ≥1:2 or positive result suggests recent or acute infection with California encephalitis virus (La Crosse virus).N/A
No special patient preparation required. Lumbar puncture should be performed using standard aseptic technique by qualified personnel. Inform the ordering physician of any bleeding disorders or anticoagulant therapy prior to procedure.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
Ig Free Light Chains in CSF
Frequently asked questions
What causes abnormal free light chains in CSF?
How often should I get this test?
Can lifestyle changes affect this test results?
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