What is the role of electrophoresis and immunofixation in the workup of multiple myeloma (MM)?

Updated: May 11, 2021
  • Author: Dhaval Shah, MD; Chief Editor: Emmanuel C Besa, MD  more...
  • Print

Serum protein electrophoresis (SPEP) is used to determine the type of each protein present and may indicate a characteristic curve (ie, where the spike is observed). Urine protein electrophoresis (UPEP) is used to identify the presence of the Bence Jones protein in urine. Immunofixation is used to identify the subtype of protein (ie, IgA lambda).

National Comprehensive Cancer Network (NCCN) guidelines also recommend the use of serum free light chain assay and plasma cell fluorescence in situ hybridization (FISH) for del 13, del 17p13, t(4;14), t(11;14), 1q21 amplification as part of the initial diagnostic workup. [2]

Chemical screening, including calcium and creatinine SPEP, immunofixation, and immunoglobulin quantitation, may show azotemia, hypercalcemia, an elevated alkaline phosphatase level, and hypoalbuminemia. A high lactate dehydrogenase (LDH) level is predictive of an aggressive lymphomalike course.

SPEP is a useful screening test for detecting M proteins. An M component is usually detected by means of high-resolution SPEP. The kappa-to-lambda ratio has been recommended as a screening tool for detecting M-component abnormalities. An M-component serum concentration of 30 g/L is a minimal diagnostic criterion for MM. In about 25% of patients, M protein cannot be detected by using SPEP.

Routine urinalysis may not indicate the presence of Bence Jones proteinuria. Therefore, a 24-hour urinalysis by means of UPEP or immunoelectrophoresis may be required. UPEP or immunoelectrophoresis can also be used to detect an M component and kappa or lambda light chains. The most important means of detecting MM is electrophoretic measurement of immunoglobulins in both serum and urine.

Did this answer your question?
Additional feedback? (Optional)
Thank you for your feedback!