@omemee There can be several causes of foamy urine. If you have a full bladder, and the urine is expelled forcefully, this can cause a foamy appearance. Dehydration can be another cause. To experience foamy urine from time to time is normal. But if you have it consistently, you may be seeing the appearance of protein in the urine. This can be caused by kidney issues, as noted in this article from WebMD https://www.webmd.com/a-to-z-guides/proteinuria-protein-in-urine

In the interest of not putting the cart before the horse, I like to look at all possible factors. While I deal with multiple myeloma, I also have kidney issues not related to the myeloma. Some people do indeed have kidney involvement from MGUS/myeloma situations; for me, the drs tested and found they are separate situations.

Reach out to your medical team and get their thoughts on what you are experiencing, based on what you see and the labwork for your particular case. Painting with a broad brush is not a good thing, that is, assuming it must be related to the MGUS.

Let me know what you find out, okay? And feel free to ask away, or reach out for support. I'm only a keyboard away!
Ginger