[Rhonda]

Test unable to determine free light chain ratio

by Rhonda on Sat Jun 27, 2015 8:05 pm

Hi

I was wondering if anyone can tell me what a negative value in a serum free kappa & lambda test means and if it is of concern that a ratio cannot be calculated.

My results were as follows:

Kappa Free Light Chains <0.11 (L) 0.33-1.94 mg/dl ref range
Lambda Free Light Chains 2.04 0.57-2.63 mg/dl ref range
Kappa-Lambda Ratio: See note.

Comment: Unable to calculate ratio due to undetectable concentration of free kappa and/or free lambda light chains.

My last lab results were within the normal range and now this.

Thank you for your help,

Rhonda

[Ron Harvot]

Re: Test unable to determine free light chain ratio

by Ron Harvot on Sat Jun 27, 2015 9:40 pm

I would ask for a re-test. The fact that your last test was all normal (assuming the test was relatively recent - last 3 months) points to a potential test aberration. I would have it re-run and, if still real low, then have a discussion with your oncology specialist.

[Rhonda]

Re: Test unable to determine free light chain ratio

by Rhonda on Sat Jun 27, 2015 10:06 pm

Thanks Ron, I didn't even think of that. My last test was May 28th, so it was only a month ago, I will ask for a new order to have it re-tested.

Thanks again.
Rhonda

[JPC]

Re: Test unable to determine free light chain ratio

by JPC on Sun Jun 28, 2015 8:50 am

Good morning Rhonda:

I recall discussing this with our multiple myeloma doc. If one or the other of the kappa or lambda (or both) is too close to zero, then the ratio no longer makes sense. It's just math. Our doc advised if one is in the normal range, and the other close too zero, then the ratio would not be looked at. The doctor would probably look at the trend of both of them individually It's a good thing to have the kappa or lambda close to zero, is my understanding. Regards,