Amino Acid Profile, Quantitative, Cerebrospinal Fluid
Use
Diagnosis and monitoring of inherited aminoacidurias. Most notably, quantitation of amino acids in CSF is useful in the diagnosis of glycine encephalopathy. CSF samples are most informative when a plasma sample is collected at the same time and ratios of the amino acid concentrations in CSF to plasma are calculated.
Special Instructions
CSF samples should be frozen immediately after collection to maintain stability. To avoid delays in turnaround time, submit separate frozen specimens for each test requested.
Limitations
False-negative results can occur, especially when the patient is affected with a mild or intermittent variant of a disorder, or when the clinical condition or dietary treatment causes secondary changes to the profile. Results should be interpreted in the context of clinical presentation and other laboratory tests.
Methodology
Mass Spectrometry
Biomarkers
LOINC Codes
- 22656-3
- 49303-1
- 72486-4
- 49549-9
- 26614-8
- 22655-5
- 22643-1
- 22644-9
- 26603-1
- 22652-2
- 22641-5
- 22650-6
- 22657-1
- 22654-8
- 22649-8
- 22653-0
- 22648-0
- 22659-7
- 9412-8
- 22642-3
- 22646-4
- 26589-2
- 26594-2
- 22647-2
- 22651-4
- 9453-2
Result Turnaround Time
4-10 days
Related Documents
For more information, please review the documents below
Specimen
Cerebrospinal Fluid
Volume
0.5 mL
Minimum Volume
0.15 mL
Container
Plastic transport tube
Collection Instructions
To avoid delays in turnaround time when requesting multiple tests on frozen samples, please submit separate frozen specimens for each test requested.
Storage Instructions
Freeze.
Causes for Rejection
Gross contamination with blood; room temperature or thawed specimen
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | Unstable |
| Refrigerated | Unstable |
| Frozen | 14 days |
Other tests from different labs that may be relevant