Clinical Evaluation of Immunoglobulin Free Light Chain ELISA for Early Diagnosis of Multiple Myeloma

Objective To evaluate the measurement of kappa and lambda immunoglobulin free light chains (FLC) in patient samples using a new enzyme-linked immunosorbent assay for early diagnosis of multiple myeloma. Methods An ELISA method for quantifying kappa and lambda free light chains were used to study serum and urine samples from patients with multiple myeloma, and the results were compared with those obtained using immunofixation electrophoresis and nephelometric immunoassay methods. Results The FLC-ELISA method had great successful rate in identifying the multiple myeloma in all 40 myeloma patients.In contrast, immunofixation electrophoresis and nephelometric immunoassay could only identify 57.5% and 85.5% of the multiple myeloma in all the myeloma patients, respectively. Furthermore, retrospective diagnosis of specimens obtained from patient indicated that the ELISA method could help early diagnosis of the disease by over two years. Conclusion The ELISA method for measuring free light chains is sensitive, accurate and reproducible. Therefore it is a useful tool for early diagnosis of multiple myeloma, monitoring the disease progression and evaluating treatment responses.