Serum Free Kappa and Lambda Light Chains (SFLC)
Description:
Measurement of SFLCs is particularly useful in free light chain disease, risk stratification in MGUS, rapid assessment of response to treatment, Waldenstroms macroglobulinaemia, assessment of residual disease and complete response, monitoring patients that cannot be assessed by electrophoresis and is an alternative to urine electrophoresis for Bence Jones proteins. The International Myeloma Working Group guidelines (2009) recommends the measurement of serum free light chain concentrations as an aid in the diagnosis, prognosis and monitoring of multiple myeloma patients.
Clinical details:
Production of SFLCs in normal individuals is around 500 mg/day from bone marrow and lymph node cells. SFLCs are rapidly cleared and metabolised by the kidneys depending on molecular size.
Reference range:
Free kappa light chains 3.30-19.40 mg/L Free lambda light chains 5.71-26.30 mg/L Kappa/Lambda ratio 0.26-1.65 Please note in patients with renal impairment, kappa/lambda ratio range is 0.37 - 3.1
Synonyms or keywords:
Free kappa and lambda light chains
Units:
mg/L
Department:
Location:
Sample type and Volume required:
Clotted (yellow SST tube) Serum.
Turnaround time:
3 working days
Contacts:
Diagnostic Immunology and Allergy Department at King's College Hospital
General Enquiry : 020 3299 8752 / 020 3299 1171
King's College Hospital
Bessemer Wing - 1st Floor
Denmark Hill
London SE5 9RS
Bessemer Wing - 1st Floor
Denmark Hill
London SE5 9RS
Last updated: 18/03/2026

