Serum Free Light Chains (SFLC)
Immunology and Allergy Overview / Directory
Purpose of the test
This test is for the quantitation of serum free light chains, both kappa and lambda.
The result will also include the Kappa: Lambda ratio.
The early identification of plasma cell dyscrasias is key to their treatment and management. “Intact” myeloma is readily detected in conventional serum electrophoresis. However, as always there are caveats to such a statement. Other forms of myeloma, light chain disease and non-secretory disease, do not exhibit monoclonal immunoglobulin in serum detectable by electrophoresis. In the case of light chain disease urine electrophoresis is the conventional diagnostic. Accurate quantitation of urinary free light chains is not without problems and hence is not an ideal tumour marker. SFLC measurement is able to detect abnormal concentrations in both of these conditions. Also difficult to detect by serum electrophoresis are cases of AL amyloidosis, where this assay has been shown to be of particular use (Reference 1).
The half-life of SFLCs is measured in hours unlike intact immunoglobulin, measured in days. This allows a rapid indication of response to therapeutic intervention (see Reference 2). This in turn may reduce the need to continue expensive drug regimes, which have less than the desired efficacy.
Sample Requirements
2 ml freshly separated serum
Storage and Transport
Serum stored at 4°C should be sent by first class post
Turnaround Time
6 days
Time Limit for Extra Tests
Five days
Factors affecting results or interpretation
All tests are compromised by prolonged transit times. For this reason, date of bleed and date of postage must be provided with each request.
Price
Price available on application - please contact adrianturner1@nhs.net. Discounts could be available for significant workloads.
(*Discounts available for significant workloads)
Contacts
Dr Ted Davies, Consultant Clinical Scientist
T 020 7737 4000 Ex 8752
John Cazabon or Rosemary Ebling, Lead Biomedical Scientists
T 020 3299 1559
References
1.Dispenzieri A, Gertz MA, Kyle RA. Determining appropriate treatment options for patients with primary systemic amyloidosis. Blood 2004; 104:2992
2.Cavallo et al. Serum Free-Lite Chain Assay in Multiple Myeloma: Clinical Correlates and Prognostic Implications etc. Blood 2005;106 (11) 3490, p974a
