Which factors affect the accuracy of serum protein electrophoresis (SPEP) results?

Updated: Jul 31, 2019
  • Author: Sherilyn Alvaran Tuazon, MD; Chief Editor: Eric B Staros, MD  more...
  • Print


The presence of an M-protein may be missed if the level is too small to be detected using SPEP. In cases where a high suspicion for a clonal plasma cell disorder is high, more sensitive tests such as a serum immunofixation or free light chain assay should be performed. In addition, when either alpha-1 antitrypsin deficiency or immunoglobulin deficiency, specific quantitation is indicated as SPEP is insensitive in these cases.

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