[blukitty]

M-spike in urine but blood tests clear: what's it mean?

by blukitty on Thu May 03, 2018 2:17 am

I recently had quite a few blood tests and a 24-hour urine collection test. My urine came back abnormal (results below) while my bloodwork was normal and so was my GAA. I am not anemic and I have no organ involvement.

What does it mean to have the urine come back positive for an M-spike but the blood tests be clear? How concerned should I be?

Immunofixation, U - Monocolonal Kappa
Impression - M-Spike in Gamma Fraction
M-Spike 46 mg / 24hr
A/G Ratio - 0.17
Gamma-Globulin - 40%
Beta - Globulin - 17%
Alpha 2 - Globulin - 24%
Apha 1 - Globulin - 5%
Albumin - 14%
Protein Concentration - 15 mg/dl
Urine Volume - 1367 ml
Collection Duration 24 hr
Total Protein - 205 mg / 24hr

[Beacon Staff]

Re: M-spike in urine but blood tests clear: what's it mean?

by Beacon Staff on Thu May 03, 2018 6:31 am

Hi blukitty,

The discussion in this other forum thread may be helpful to you. It was started with a question very similar to yours, but the background information is different, so we've kept your post in its own thread.

"M-spike in urine but not blood: is that possible?" (started July 5, 2017)

Did your blood tests include:

1. A serum protein electrophoresis (SPEP) test?
2. A serum immunofixation electrophoresis (IFE) test?
3. A serum free light chain test, which yields kappa and lambda levels as well as a kappa-lambda ratio.

In regard to the third (serum free light chain) test, it's important that the test be for free light chains, not total light chains. It's also important that it be a serum, not urine, test.

[blukitty]

Re: M-spike in urine but blood tests clear: what's it mean?

by blukitty on Thu May 03, 2018 12:28 pm

Thank you for the reply. All blood tests came back normal.

[TerryH]

Re: M-spike in urine but blood tests clear: what's it mean?

by TerryH on Thu May 03, 2018 3:45 pm

Interesting.

Since it probably will play a role later in this discussion, I'll note that your urine M-spike (Bence Jones protein) is low.

What were (verbatim) the results of your serum immunofixation, and what were the results of your serum free light chain test (kappa, lambda, and kappa/lambda)?