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23163 Free Light Chains, Serum

Free Light Chains, Serum
Test Code: FLC-S
Synonyms/Keywords
​Kappa and Lambda, Kappa/Lambda ratio, K/L ratio
Test Components
​Serum Free Kappa Light Chains and Serum Free Lambda Light Chains
Useful For
​Quantitation of serum free light chain (FLC) levels is important for diagnosis and monitoring of monoclonal gammopathies, including Light Chain Diseases.
Specimen Requirements
Fasting Required Specimen Type Preferred Container/Tube Acceptable Container/Tube Specimen Volume Specimen Minimum Volume
(allows for 1 repeat)
Pediatric Minimum Volume
(no repeat)
​No Serum​  Red Top Tube (RTT)​ Serum Separator Tube (SST)​ 1.0 mL​ 0.5 mL​ 0.5 mL​
Specimen Stability Information
Specimen Type Temperature Time
Serum​ ​ Refrigerate​ 3 weeks​
Frozen 1 year​
Rejection Criteria
Plasma samples
Gross hemolysis​
Performing Laboratory Information
Performing Location Day(s) Test Performed Analytical Time Methodology/Instrumentation
Marshfield​ Monday through Friday​ 6-8 hours​ Turbidimetric method/The Binding Site Optilite analyzer​
Test Information
The quantitation of immunoglobulin free light chains by nephelometry uses free light chain antisera from The Binding Site, Ltd.
Reference Range Information
Performing Location Reference Range
Marshfield​ Kappa Free Light Chain: 0.33-1.94 mg/dL
Lambda Free Light Chain: 0.57-2.63 mg/dL
Kappa/Lambda ratio: 0.26-1.65​
Interpretation
​Diagnosis cannot be made and treatment must not be given on the basis of free light chain measurements alone. Clinical history and other laboratory findings must be taken into account.  Elevation of both kappa and lambda free light chains with a normal K/L ratio may occur due to polyclonal hypergammaglobulinemia or impaired renal clearance.
Outreach CPTs
CPT Modifier
(if needed)
Quantity Description Comments
83521​ 2​ Kappa Serum Free Light Chain, Lambda Serum Free Light Chain​
Synonyms/Keywords
​Kappa and Lambda, Kappa/Lambda ratio, K/L ratio
Test Components
​Serum Free Kappa Light Chains and Serum Free Lambda Light Chains
Ordering Applications
Ordering Application Description
​Centricity ​Free Light Chains, Serum
​Cerner ​Free Light Chains, Serum
If the ordering application you are looking for is not listed, contact your local laboratory for assistance.
Specimen Requirements
Fasting Required Specimen Type Preferred Container/Tube Acceptable Container/Tube Specimen Volume Specimen Minimum Volume
(allows for 1 repeat)
Pediatric Minimum Volume
(no repeat)
​No Serum​  Red Top Tube (RTT)​ Serum Separator Tube (SST)​ 1.0 mL​ 0.5 mL​ 0.5 mL​
Specimen Stability Information
Specimen Type Temperature Time
Serum​ ​ Refrigerate​ 3 weeks​
Frozen 1 year​
Rejection Criteria
Plasma samples
Gross hemolysis​
Useful For
​Quantitation of serum free light chain (FLC) levels is important for diagnosis and monitoring of monoclonal gammopathies, including Light Chain Diseases.
Test Components
​Serum Free Kappa Light Chains and Serum Free Lambda Light Chains
Reference Range Information
Performing Location Reference Range
Marshfield​ Kappa Free Light Chain: 0.33-1.94 mg/dL
Lambda Free Light Chain: 0.57-2.63 mg/dL
Kappa/Lambda ratio: 0.26-1.65​
Interpretation
​Diagnosis cannot be made and treatment must not be given on the basis of free light chain measurements alone. Clinical history and other laboratory findings must be taken into account.  Elevation of both kappa and lambda free light chains with a normal K/L ratio may occur due to polyclonal hypergammaglobulinemia or impaired renal clearance.
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Performing Laboratory Information
Performing Location Day(s) Test Performed Analytical Time Methodology/Instrumentation
Marshfield​ Monday through Friday​ 6-8 hours​ Turbidimetric method/The Binding Site Optilite analyzer​
For billing questions, see Contacts
Outreach CPTs
CPT Modifier
(if needed)
Quantity Description Comments
83521​ 2​ Kappa Serum Free Light Chain, Lambda Serum Free Light Chain​
For most current information refer to the Marshfield Laboratory online reference manual.