If I am going to use sFLC tests how do they fit into my laboratory protocols?
The preferred option is to measure FLCs alongside SPE at the time of the presentation blood sample. SPE will identify IIMM patients while FLC assays will identify LCMMs, most NSMMs and other FLC diseases such as AL amyloidosis. Low concentration, intact immunoglobulin MGUS sera (less than 2-5g/L) will not be detected using these two procedures. A strategy of performing SPE and IFE as a screen for FLC monoclonal proteins and not FLC immunoassays will result in some patients with LCMM, NSMM and AL amyloidosis being missed. FLC assays, performed on a patient’s presentation sample, are also important for providing a baseline for subsequent disease monitoring. For easy interpretation, results should be reported using a logarithmic κ/λ plot, alongside existing clinical data. When monitoring patients with FLC diseases, results should be reported alongside other analyses. IFE may add little to the combined use of SPEand FLC tests apart from identifying some low level intact immunoglobulin MGUS
