N Latex FLC serum free light-chain assays in patients with renal impairment.

Background: The aim of this study was to establish ranges for N Latex free light-chain (FLC) monoclonal-based nephelometric assays in patients with renal impairment.

Methods: In this retrospective study, serum samples from 284 patients with chronic kidney disease (CKD) stages 1-5 were measured with N Latex and Freelite FLC reagents on the Siemens BNII system and compared with controls without renal impairment.

Results: Both κFLC and λFLC concentrations increased with the N Latex FLC and the Freelite assays with each increment in CKD stage.

Clinical comparison of new monoclonal antibody-based nephelometric assays for free light chain kappa and lambda to polyclonal antibody-based assays and immunofixation electrophoresis.

Background: New monoclonal antibody-based assays for serum-free light chains (FLC) have become available.

Methods: In a clinical study with 541 patients, the new N Latex FLC assays were compared with the Freelite FLC assays and immunofixation electrophoresis (IF).

Results: Comparison of the different FLC kappa (κ) assays showed a slope of 0.

N Latex FLC - new monoclonal high-performance assays for the determination of free light chain kappa and lambda.

Background: High serum concentrations of monoclonal free light chain (FLC) kappa or lambda are markers of plasma cell dyscrasia.

Methods: We developed new, latex-enhanced, specific nephelometric assays based on monoclonal antibodies for the determination of FLC kappa and lambda in serum, EDTA plasma and Li-heparin plasma for use on the Siemens BN™ systems.

Results: Reference ranges were determined from 369 samples: FLC kappa 6.