[zephyrus]

Urine immunofixation tests

by zephyrus on Thu Jun 27, 2013 3:29 pm

My wife had a stem cell transplant about a year ago to treat her light chain myeloma, is on Revlimid maintenance therapy and has seen her numbers continue to improve after the transplant. Both urine and serum protein electrophoresis are normal as is her serum free light chain (FLC) tests. The disease only shows up in the urine immunofixation tests and then, only at one lab. (She has tests done at MD Anderson and at her local oncologist.) I am wondering whether the 2 labs are doing the same type of test or whether there are differing levels of sensitivity between the 2 labs.

One lab describes the test like this:

IMMUNOFIXATION ELECTRO, URINE
URINE IMMUNOFIXATION INTERP
The follow-up urine protein immunofixation electrophoretic patterns
obtained with the use of antisera against IgG, IgA, IgM, bound kappa and
bound lambda light chains, free kappa and free lambda light chain proteins
are positive for a kappa Bence-Jones proteinuria.

The other lab like this:

Immunofixation, urine
Interpretation UEP
No paraprotein detected.

Any similar experiences?

I'm also wondering whether other light chain myeloma patients have also had this experience where the FLC is normal but B-J proteins show up in the urine.

[pinball]

Re: Urine immunofixation tests

by pinball on Tue May 13, 2014 10:37 pm

The same exact thing for me - exact in that:

"Both urine and serum protein electrophoresis are normal as is her serum free light chain (FLC) tests. The disease only shows up in the urine immunofixation tests and then, only at one lab"

Even down to each way you have described the results (for the positive and the negative both from 2 different labs <wording is the same for each as in your examples>) - one difference though is that the second lab (the negative immunofixation, that was 10 months ago, so it's possible that that lab may not pickup immunofixation only).

So much to learn ... Thanks.