Immunoglobulin G (IgG) in cerebrospinal fluid (CSF) by nephelometry
This test measures the level of Immunoglobulin G, a type of antibody found in your spinal fluid, which helps protect your nervous system.
["IgG in CSF may help diagnose or monitor conditions affecting your brain and spinal cord."]
Key facts at a glance
- LOINC
- 2470-3
- Short code
- IgG/Alb CSF
- Synonyms
- IgG/Alb CSF
- Category
- chemistry
- Sample
- csf
- Container
- Sterile tube
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 82784
- 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 to check for infections, inflammation, or other conditions that affect the central nervous system, such as multiple sclerosis, meningitis, or certain types of brain tumors. It can also help determine if antibodies are present in your spinal fluid that might indicate an autoimmune disease.
What does a result mean?
The results are compared to a reference range, which can vary by lab. Elevated IgG levels in CSF may suggest conditions like multiple sclerosis, where the immune system mistakenly attacks the central nervous system. Very low levels might indicate a blockage in the flow of cerebrospinal fluid or certain infections.
How is the test performed?
A small amount of cerebrospinal fluid is collected through a procedure called a lumbar puncture (spinal tap). The fluid is then analyzed in a lab using nephelometry, a method that measures how particles scatter light to determine antibody concentration.
What should I expect before or after the test?
Before the test, you may be asked to fast or avoid certain medications, but this depends on your specific situation. Afterward, you might experience mild soreness at the injection site, and you may need to stay lying down for a short time. Follow your healthcare provider’s instructions for recovery.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical significance: IgG in CSF is critical for diagnosing conditions like multiple sclerosis, where abnormal IgG levels can indicate demyelination or inflammation. It can also help identify infections (e.g., viral or bacterial meningitis), autoimmune diseases, or tumors affecting the central nervous system. Abnormal results prompt further evaluation, such as additional imaging or tests.
Short name
IgG in CSF
Frequently asked questions
What does an elevated IgG level in CSF usually indicate?
Can IgG levels in CSF change over time?
Does diet or medications affect IgG levels in CSF?
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