Kappa/Lamba Light Chains, Free with Ratio, Serum : 11234

Test Code
FLTCHN : 11234

Alias/See Also
Immunoglobulin Free Light Chains

CPT Codes

This test includes Kappa Light Chain, Free,   Lambda Light Chain, Free, and  the  Kappa/Lambda  Light Chains, Free Ratio

Plain red top tube or Serum Separator Tube (SST).

Transport Container
Centrifuge the Serum Separator Tube (SST); if plain red top, centrifuge and aliquot serum (2.0 mL, minimum 1.0 mL) into a standard transport tube.

Transport Temperature
Room temperature.

Specimen Stability
Room temperature: 72 hours; Refrigerated: 21 days; Frozen: 30 days

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Gross hemolysis, gross lipemia, microbial contamination, heavy visible particulate


Setup Schedule
Monday - Friday

Report Available
2-5 days

Reference Range
Kappa Light Chain, Free, Serum                                      3.3-19.4 mg/L 
Lambda Light Chain, Free, Serum                                    5.7-26.3 mg/L 
Kappa/Lambda Light Chains Free with Ratio, Serum       0.26-1.65 

Clinical Significance
Immunoglobulin molecules consist of two identical heavy chains (alpha (α), delta (δ), epsilon (ε), gamma (γ), and mu (μ)) which define the immunoglobulin class and two identical light chains, kappa (κ) and lambda (λ). Each light chain is covalently linked to a heavy chain and the two heavy chains are linked covalently at the hinge region. In healthy individuals, the majority of light chain in serum exists in this form, bound to heavy chain. However, low levels of free light chain (FLC) are found in serum of normal individuals due to the over-production and secretion of FLC by the plasma cells. While the molecular weight of both light chains is ≈22.5kD, in serum κ free light chain (κ – FLC) exists predominantly as monomer and λ free light chain (λ- FLC) as a covalently linked dimer with a molecular weight of ≈45kD. This will lead to a differential glomerular filtration rate for κ – FLC and λ- FLC and may explain the observed ratio of κ – FLC to λ- FLC of 0.625 in serum compared to the ratio of bound κ to λ of 2.0. Elevated serum levels of monoclonal FLC are associated with malignant plasma cell proliferation (e.g., multiple myeloma), amyloid light chain (AL) amyloidosis and light chain deposition disease. Raised serum levels of polyclonal FLC may be associated with autoimmune diseases such as systemic lupus erythematosus.

Performing Laboratory
med fusion

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.