D-alanine concentration in cerebrospinal fluid
This test measures the level of D-alanine, an amino acid, in your cerebrospinal fluid (the fluid surrounding your brain and spinal cord). It may be used to evaluate conditions affecting the blood-brain barrier or central nervous system metabolism.
["D-alanine levels in CSF can help diagnose or monitor certain neurological or metabolic disorders."]
Key facts at a glance
- LOINC
- 34284-0
- Short code
- D-ALA Ur-sCnc
- Synonyms
- D-ALA Ur-sCnc
- Category
- chemistry
- Sample
- urine
- Container
- Sterile urine container
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Specimen volume
- 10 mL
- Stability
- Room temperature: 2h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 4–24 hours
- Order
- routine
Why is this test done?
Your doctor may order this test if you have symptoms like headaches, seizures, or neurological issues that suggest an abnormality in the fluid surrounding your brain and spinal cord. It could also be part of a broader evaluation for metabolic disorders or conditions affecting how nutrients pass between blood and brain tissue.
What does the test involve?
A small amount of cerebrospinal fluid is collected through a procedure called a lumbar puncture (spinal tap). The fluid is then analyzed for D-alanine concentration using a specialized laboratory method.
What do the results mean?
Abnormal results may indicate conditions such as certain metabolic disorders, blood-brain barrier dysfunction, or other neurological conditions. However, interpretation depends on clinical context and other test results.
What preparation is needed?
No special preparation is typically required. You may be asked to fast or avoid certain medications, but this depends on your doctor’s instructions. Follow their guidance closely.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical significance: Elevated or low D-alanine levels in CSF can be associated with metabolic disorders like aminoacidopathies, mitochondrial diseases, or conditions affecting the blood-brain barrier. This test is often used in conjunction with other diagnostic tests to provide a clearer picture of neurological or metabolic health.
Short name
D-Ala CSF
Frequently asked questions
What is the normal range for this test?
How long does it take to get results?
Can I eat or drink before this 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