HIV Antibody Test (IgG) in Cerebrospinal Fluid (CSF) – Confirmatory
This test measures HIV antibodies in your cerebrospinal fluid (CSF) to help diagnose HIV infection in the central nervous system, such as meningitis or encephalitis.
["Assesses HIV exposure in the brain/spinal fluid for neurological complications."]
Key facts at a glance
- LOINC
- 31430-2
- Short code
- HIV1 IgG CSF Ql
- Synonyms
- HIV1 IgG CSF Ql
- 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 This Test Is Done
Your healthcare provider may order this test if you have symptoms like severe headaches, confusion, or neurological issues that could be linked to HIV affecting the brain. It’s also used in cases where HIV is suspected after a positive blood antibody test but symptoms don’t align with typical infection sites.
What to Expect Before the Test
You’ll likely have a lumbar puncture (spinal tap) where a small needle is inserted into your lower back to collect CSF. The procedure is quick but may cause mild discomfort. No special preparation is needed, but inform your doctor about any medications you’re taking.
What the Test Results Mean
Positive results indicate the presence of HIV antibodies in your CSF, suggesting active HIV infection in the central nervous system. Negative results mean no detectable antibodies, but further testing may still be needed to rule out other conditions.
Common Causes of False Results
False positives or negatives can occur due to recent HIV exposure, cross-reactions with other infections, or lab errors. Your doctor will discuss results in context with your symptoms and other tests.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance
Short name
HIV IgG CSF Confirmatory
Frequently asked questions
This test helps diagnose HIV-related neurological diseases, such as HIV-associated dementia or meningitis, which can affect your brain function. Early detection allows for targeted treatment to manage symptoms and slow disease progression.
A positive result means HIV antibodies are found in your spinal fluid, which may indicate HIV affecting your nervous system. Your doctor will work with you to determine the best treatment plan, which may include antiretroviral therapy (ART) to manage symptoms and protect your brain health.
Yes, this test is used specifically for CSF to check for HIV in the central nervous system. Even if your blood test shows HIV antibodies, this test helps assess whether the virus is active in your brain or spinal fluid.
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