Immunoglobulin Kappa Free Light Chain, Spinal Fluid
Use
This test is particularly useful for diagnosing multiple sclerosis and other demyelinating conditions. It helps evaluate patients who present with a clinically isolated syndrome that mimics multiple sclerosis symptoms like headaches, optic neuritis, and fatigue. The test is recommended when imaging findings are atypical or in demographics where multiple sclerosis is less common, such as children, elderly, or non-White populations. This test is not useful if a clear diagnosis is already established, as a positive result does not correlate with disease severity or outcomes.
Special Instructions
If not ordering electronically, complete, print, and send a Neurology Specialty Testing Client Test Request (T732) with the specimen. For evaluation specifically linked to multiple sclerosis, consider coordinating with available tests such as SFIG, Cerebrospinal Fluid IgG Index Profile, and OLIG Oligoclonal Banding tests.
Limitations
The test is not specific for multiple sclerosis because CSF-specific immunoglobulin synthesis may be detected in other neurologic diseases like infectious, inflammatory, cerebrovascular, autoimmune, and paraneoplastic diseases. It does not require a paired serum specimen and provides an objective quantitative result. Caution is advised as improper specimen collection or handling can lead to diagnostic confusion.
New York Approved
Methodology
Immunoassay (Nephelometry)
Biomarkers
LOINC Codes
- 48774-4
- 48774-4
Result Turnaround Time
1-3 days
Related Documents
For more information, please review the documents below
Specimen
Cerebrospinal Fluid
Volume
1 mL
Minimum Volume
0.5 mL
Container
Sterile vial
Collection Instructions
Label specimen as spinal fluid.
Causes for Rejection
Gross hemolysis
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 24 hours |
| Refrigerated | 72 hours |
| Frozen | 28 days |