No abstract

Background: The objective of this study was to evaluate the efficiency of free light chain (FLC) analysis in comparison to serum protein electrophoresis (SPE) for detecting M-proteinemia. Methods: A total of 553 consecutive patients for whom evaluation of M-proteinemia was requested were included in this study. For all patients, serum FLC analysis and SPE followed by pentavalent immunofixation analysis was performed. Identification of monoclonal bands was performed using specific antisera. FLC analysis was performed using the Modular P analyzer in accordance with the manufacturer's recommendations. Local reference ranges for FLCs on this platform were established based on samples from patients with a normal electrophoretic pattern wno monoclonal bands, no hypo-or hypergammaglobulinemia, no acute phase pattern and normal kidney function, i.e., estimated glomerular filtration rate (eGFR) )60 mL/minx. Results

In high resolution agarose gel electrophoresis, monoclonal bands of low concentration often remain undetected. In split-β agarose gel electrophoresis as well as capillary electrophoresis monoclonal bands more often were not separated from the regular protein bands.