title: [Comparative analysis of immunoglobulin free light chains quantification by Freelite™ (The Binding Site) and N Latex FLC (Siemens) methods].
abstract: Serum immunoglobulin free light chain assay has proved to be an invaluable biological tool for diagnosis and monitoring of monoclonal gammopathies including multiple myeloma, primary amyloidosis, solitary plasmocytoma or monoclonal gammopathy of undetermined significance. Free light chain quantification, although essential, cannot be achieved by serum protein electrophoresis either because there is no monoclonal peak or because the peak is hidden in beta or alpha-globulin fraction. As for serum protein immunofixation, this major test allows the typing of the paraprotein but does not provide any quantitative evaluation. Hence, the development of free light chain assays constitutes a significant improvement in the management of these patients. In this context, we compared the results of serum free light chains quantification and of calculation of the ratio kappa/lambda, indicator of monoclonality, in forty samples performed on BN ProSpec(®) analyzer, with the two methods available on the European market. This comparative analysis provided evidence of a good correlation of results between the two methods. However, we noticed clinically significant differences in four samples. In addition, this evaluation highlighted the fact that all free light chain results must be biologically validated on the light of different criteria such as serum protein electrophoresis, serum protein immunofixation, presence of proteinuria, presence of renal failure, and additional clinical data, in order to ascertain the best interpretation for clinical use.
authors: Laboratoire central de biochimie, Hôpital Robert Debré, CHU de Reims, France. nschneider@chu-reims.fr
authors: Nathalie
authors: N
authors: Schneider
authors: Alain
authors: A
authors: Wynckel
authors: Brigitte
authors: B
authors: Kolb
authors: Emilie
authors: E
authors: Sablon
authors: Philippe
authors: P
authors: Gillery
authors: François-Xavier
authors: FX
authors: Maquart
mesh_terms: D001665:Binding Sites; D006801:Humans; D007118:Immunoassay / Q000379:methods; D007147:Immunoglobulin Light Chains / Q000032:analysis* / Q000097:blood / Q000378:metabolism; D007840:Latex; D008991:Monitoring, Physiologic / Q000379:methods; D009391:Nephelometry and Turbidimetry / Q000379:methods; D010265:Paraproteinemias / Q000097:blood / Q000175:diagnosis* / Q000276:immunology; D011379:Prognosis; D011786:Quality Control; D011933:Reagent Kits, Diagnostic; D015203:Reproducibility of Results
chemical_list: D007147:Immunoglobulin Light Chains; D007840:Latex; D011933:Reagent Kits, Diagnostic
keywords: comparison of methods; multiple myeloma; renal failure; serum free light chains