[lwem]

M-Spike "admixed" with polyclonal background?

by lwem on Sun Sep 11, 2016 6:19 am

Hi all -

For the second month, my husband's SPEP has stated that the M-spike appears to be an over-estimate because it is "admixed within a background of polyclonal immunoglobulins."

I understand that this means the M-spike estimate represents a combination of other polyclonal immunoglobulin "spikes" and the monoclonal protein is actually smaller than the estimate.

Has anyone else had this same language reported on their SPEP M-spike interpretation?

I am also wondering whether this might be indicative of an autoimmune condition that we should ask his primary care physician about?

Thank you!

Laurie

[Multibilly]

Re: M-Spike "admixed" with polyclonal background?

by Multibilly on Sun Sep 11, 2016 6:30 pm

This sort of situation can and does occur from time to time. Over time, one's M-protein can evolve and develop a slightly different electro­chemical makeup that may cause it to migrate on top of areas of an SPEP that have large, dense populations of normal proteins. In turn, this can make it difficult to accurately quantify that M-spike, especially if it is a small M-spike. This can also occur if the M-spike migrates into the beta or alpha regions of an SPEP graph.

In these situations, you also need to be monitoring your immunoglobulin and free light chain values for any signs of disease progression. You can also avail yourself to the new Hevylite assay, which is able to get around these sorts of measurement challenges.

You might start suspecting an autoimmune disease (or infection, inflammation, etc), if one or more of your quantified immunoglobulin levels started to really rise substantially without a com­men­su­rate rise in the M-spike level.

[lwem]

Re: M-Spike "admixed" with polyclonal background?

by lwem on Sun Sep 11, 2016 10:28 pm

Thank you, Multibilly.

His M-spike is very small at this point. He was in complete remission (CR) until a few months ago, so not really worried there about those results. His immunoglobulins are also very low (including his uninvolved immunoglobulins), so we will monitor his next results.

Thank you for your help!