N Latex FLC kappa and N Latex FLC lambda AssaysThe first immunoassay with clearance for evaluation of monoclonal gammopathies of undetermined significance (MGUS).1,2
N Latex Free Light Chain (FLC) kappa and lambda assays enable more-reliable management of patients with monoclonal gammopathies. Designed for use on nephelometric Atellica® NEPH 630* and BN™ Systems, these high-sensitivity assays provide:
- Concordance with IMWG recommendations and other international guidelines
- A single reference range independent of patients’ kidney status
- Reliable results without possible value drift over time due to use of monoclonal antibodies and lot-to-lot consistency
- One kit for all sample types: serum, plasma, urine, and CSF
Benefits
Monoclonal antibodies provide significant advantages in analytical performance:
- Higher consistency in results obtained from different reagent lots enables early detection of changes in disease activity and subsequent adjustments to therapy, and ultimately contributes to improved patient management and outcomes.
- In research studies, monoclonal FLC assays produced no false-positive κ/λ ratios in patients with renal impairment.3-5 In comparison, the false-positive rate of polyclonal FLC assays in patients with renal impairment was 8–36%.6,7
Free light chain assay results might be affected by patients' kidney status. The iStopMM study revealed inaccuracies in reference intervals and ratios for a commonly used assay.8
Avoid potential patient misclassification with N Latex FLC assays:
- Simplifies identification of patients with monoclonal gammopathies with one clear, easy-to-interpret reference range for all patients, including those with impaired renal function.
- Minimizes the risk of patient misclassification due to human error and/or initial patient misclassification.
- Helps avoid unnecessary referrals and unnecessary invasive diagnostics.
- Supports more-accurate monitoring of response to therapy and allows better comparison of FLC data obtained from FLC assays in different clinical trials.
High clinical specificity enables clinicians to confidently identify patients not affected by monoclonal disease.
- High specificity helps prevent misdiagnosis of malignant disorders in non-affected individuals.
- Universal reference range independent of renal impairment simplifies result interpretation.
- Correlation of the FLC kappa/lambda ratio produced by N Latex FLC assay is accurate for samples at both high- and low-end concentrations vs. the ratio produced by the FREELITE assay, which can be severely affected as shown in the graph above.
Nephelometry offers analytical advantages over turbidimetry in terms of precision and sensitivity, including antigen-excess security, for confidence in results. N Latex FLC kappa and lambda assays:
- Use built-in pre-reaction protocols for detection of antigen excess.
- Provide more-consistent results.
- Generate fewer false-low test results, even in samples with very high FLC concentrations.
- Reduce the need for costly reruns.
Nephelometry has been recommended by the IMWG and ESMO guidelines for use with FLCs and immunoglobulins respectively.
N Latex FLC assay components help labs reduce costs with flexible, reagent-independent packaging.
All N Latex FLC components can be ordered separately, so you can ensure an adequate supply of standard and controls while eliminating waste.
Monoclonal antibodies provide significant advantages in analytical performance:
- Higher consistency in results obtained from different reagent lots enables early detection of changes in disease activity and subsequent adjustments to therapy, and ultimately contributes to improved patient management and outcomes.
- In research studies, monoclonal FLC assays produced no false-positive κ/λ ratios in patients with renal impairment.3-5 In comparison, the false-positive rate of polyclonal FLC assays in patients with renal impairment was 8–36%.6,7
FLC testing in MGUS evaluation
Evaluation of monoclonal gammopathies of undetermined significance (MGUS) is very important as it is seen as a precursor to multiple myeloma. Early detection of multiple myeloma facilitates early treatment with a higher patient survival rate.
Learn more about MGUS and progression to multiple myeloma.
Technical Details
Analytical specifications for Atellica NEPH 630 and BN Systems
Assay principle
Latex-enhanced immunonephelometry
Sample type
Human serum, EDTA plasma, heparinized plasma†, CSF†, urine†
Reference range
FLC kappa: 6.7–22.4 mg/L
FLC lambda: 8.3–27.0 mg/L
FLC ratio: 0.31–1.56
Initial measuring ranges
3.5–110 mg/L for FLC kappa
1.9–60 mg/L for FLC lambda
Total measuring range
0.17–≥2,000 mg/L for FLC kappa
0.47–≥6,000 mg/L for FLC lambda
Measuring time
12 minutes
Onboard reagent stability
2 weeks (Atellica NEPH 630* and BN ProSpec Systems)
5 days (6 days with evaporation stoppers) on BN II System
Calibration frequency
6 weeks
Precision
Repeatability: <5%
Within-lab: <6.5%
Antigen-excess security
FLC kappa: up to 23,000 mg/L
FLC lambda: up to 57,000 mg/L
Webinars
Serum free light chains testing in monoclonal gammopathies
Learn about the clinical and laboratory aspects impacting serum free light chains testing in diagnosis and monitoring of monoclonal gammopathies.
Excluding intrathecal inflammation using the kFLC index in CSF
Understand the concept of excluding intrathecal inflammation by measuring kappa free light chain (kFLC) in CSF and serum and hear the results of a prospective multicenter validation study of this new laboratory workflow that integrates the free light chains kappa quotient in CSF analysis.
Diagnosis and management of MGRS
Learn about the significance of monoclonal gammopathy of renal significance (MGRS), including diagnosis and management of the disease.
The importance of FLC testing in MGUS patients
Understand the key role of free light chain (FLC) testing in the detection and monitoring of MGUS.
Related Topics
BN II System
Fully automated analyzer that offers an ideal fit for mid- to high-volume plasma proteins testing and provides confidence in results.
Atellica NEPH 630 System
Mid-volume dedicated nephelometric system that provides smart, simple, and secure protein testing.
Plasma Proteins Webinars
On-demand webinars feature key opinion leaders on a variety of hot clinical topics, including FLC and SAA testing, the role of diagnostic testing in disease diagnosis and management, results of recent studies, testing recommendations, and more!
