utility of immunofixation in complementing and empowering serum protein electrophoresis in the diagnosis of paraproteinemia: experience at a tertiary care center

Background: ‘m’ proteins or paraproteins refer to immunoglobulins that are produced by clonal plasma cells and are a characteristic feature of monoclonal gammopathies. routine electrophoresis on agarose gel and immunofixation can be used to detect immunoglobulin paraprotein (m-protein). we aimed to evaluate the performance of agarose gel electrophoresis alone and in combination with immunofixation for detecting serum m-proteins. methods: one hundred and twenty-three patients suspected of paraproteinemia were evaluated. routine serum protein electrophoresis (spe) and immunofixation electrophoresis (ife) protocols were performed.  data from spe, and spe-ife (gel images and electrophoretograms) were collected and reviewed. results: 21% cases were confirmed using the spe-ife combination, and among them, 33% had positive light chain (λ) only on ife. similarly, nine cases with biclonal gammopathy on spe were characterized by ife. conclusion: ife can be a confirmatory test in cases where spe results are not reliable and it can be a complementary test when characterization of the m protein detected on spe is required.