Sign in →

Test Code KCSFP Immunoglobulin Kappa Free Light Chain, Spinal Fluid

Reporting Name

Kappa Free Light Chain, CSF

Performing Laboratory

Mayo Clinic Laboratories in Rochester

Useful For

Diagnosis of multiple sclerosis and other demyelinating conditions

Method Name

Only orderable as part of a profile. For more information see MSP3 / Multiple Sclerosis (MS) Cascade, Serum and Spinal Fluid.

 

Nephelometry


Ordering Guidance


For evaluation of multiple sclerosis, the following are also available as individually orderable tests:

-SFIG / Cerebrospinal Fluid IgG Index Profile, Serum and Spinal Fluid

-OLIG / Oligoclonal Banding, Serum and Spinal Fluid



Specimen Required


Only orderable as part of a profile. For more information see MSP3 / Multiple Sclerosis (MS) Cascade, Serum and Spinal Fluid.

 

Specimen Type: Spinal fluid (CSF)

Container/Tube: Sterile vial

Specimen Volume: 1 mL

Collection Instructions:

1. Submit CSF from collection vial number 4 (preferred); vial number 1, 3, and 2 are also acceptable (in this order).

2. Label specimen as CSF.


Specimen Type

CSF

Specimen Minimum Volume

0.5 mL

Specimen Stability Information

Specimen Type Temperature Time
CSF Frozen (preferred) 28 days
  Refrigerated  72 hours
  Ambient  24 hours

Reject Due To

Gross hemolysis Reject
Gross icterus OK

Reference Values

Only orderable as part of a profile. For more information see MSP3 / Multiple Sclerosis (MS) Cascade, Serum and Spinal Fluid.

 

Medical decision point: 0.1000 mg/dL

Positive: ≥0.1000 mg/dL

Borderline: 0.0600 mg/dL-0.0999 mg/dL

Negative: <0.0600 mg/dL

Interpretation

When result is less than 0.0600 mg/dL, the kappa free light chain concentration measured in cerebrospinal fluid (CSF) is lower than the threshold associated with demyelinating disease. This is a negative result. Testing for oligoclonal banding is not performed. Clinical correlation is recommended.

 

When result is from 0.0600 to 0.0999 mg/dL, the kappa free light chain concentration measured in CSF is slightly elevated but not above the medical decision point of 0.1000 mg/dL associated with demyelinating disease. This is a borderline result. Reflexing to oligoclonal bands will be automatically performed and clinical correlation is recommended.

 

When result is greater than or equal to 0.1000 mg/dL, the kappa free light chain concentration measured in CSF is at or greater than the threshold associated with demyelinating disease. This is a positive result. These findings, however, are not specific for multiple sclerosis (MS) because CSF-specific immunoglobulin synthesis may also be detected in patients with other neurologic diseases (infectious, inflammatory, cerebrovascular, autoimmune, and paraneoplastic). Clinical correlation is recommended. Automatic reflexing to oligoclonal bands will occur.

Day(s) Performed

Monday through Friday

Report Available

1 to 3 days

Test Classification

This test has been modified from the manufacturer's instructions. Its performance characteristics were determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.

CPT Code Information

83521

LOINC Code Information

Test ID Test Order Name Order LOINC Value
KCSFP Kappa Free Light Chain, CSF 48774-4

 

Result ID Test Result Name Result LOINC Value
KCSFP Kappa Free Light Chain, CSF 48774-4