Urine Free Light Chains (Kappa and Lambda) with Ratio

Synonyms

  • BENCE - JONES PROTEINS
  • FLC
  • FREE KAPPA AND LAMBDA LIGHT CHAINS, URINE
  • FREE KAPPA/LAMBDA URINE
  • KAPPA / LAMBDA LIGHT CHAINS, URINE, 24 HOUR
  • LAB734

Cerner Name

Free Kappa/Lambda Urine

Clinical Info

This test is a latex-enhanced, immunoassay that provides ultrasensitive detection and quantitation of free light chains (FLCs) in serum or urine earlier than electrophoresis. It is an aid in the diagnosis and treatment of multiple myeloma, lymphocytic neoplasms, Waldenstroms macroglobulinemia, and connective tissue diseases, such as systemic lupus erythematosus. Approximately 15% of all cases of multiple myeloma produce only free kappa or lambda light chains in excess. These patients frequently show no abnormality on serum protein electrophoresis. Quite often urine is tested for the presence of these light chains, which are also called Bence Jones Proteins. However, the FLCs entering the urine are strongly influenced by renal tubular function. When clonal proliferation of plasma cells starts to develop, the FLC concentration increases in serum. Since these small particles are rapidly cleared by the renal tubules, urine tests for FLCs remain negative until the tumor mass expands, and the FLCs in serum exceed the resorptive capacity of the renal tubules. Therefore, the measurement of FLCs in serum is an alternative to less sensitive urine testing. Changing concentrations of FLCs in serum relate better to changing tumor load than to concentrations in urine.

Specimen Sources

Urine, Catheter Urine, Clean Catch

Specimen Types

Urine

Specimen Volume

2 mL Urine (1mL min) from Random or 24 hours collection

Container

Urine Transport

Collection Instructions

Container/Tube: Plastic, leakproof container
Specimen: 2 mL Urine from Random or 24 Hour collection (1.5 mL min)
Transport Temperature: Refrigerated

Transport Instructions

Refrigerated

Specimen Stability

Methodology

Turbidimetric

Days Performed

Monday - Saturday

Performing Laboratories

Northwell Health Laboratories

CPT

83521

PDM

5905920

Results
Component Name Base Name Common Name External Name
FREE KAPPA URINE FREEKAPPAUR FREE KAPPA URINE Free Kappa Urine
FREE LAMBDA URINE FREELAMBDA FREE LAMBDA URINE Free Lambda Urine
KAPPA/LAMBDA RATIO URINE KAPLAMBDAU KAPPA LAMBDA RATIO URINE Kappa/Lambda Ratio Urine

Result Interpretation

Free Kappa/Lambda Ratio:         0.070 - 6.20
Free Lambda, Random Urine:  ≤ 6.99 mg/L
Free Kappa, Random Urine:     ≤8.99 mg/L

Forms
Immunology LAB734 build edit