I have MGUS...mine shows slightly in bloodwork with a small M spike. I read sometimes if the cell is small, it'll pass into urine, and not be detected in the blood. I have not had a urine(Bence Jones) test, but mine shows Igg kappa in blood. I also have very low IGM, which are white cells that fight infection. My oncologist has me scheduled for a bone marrow test this Friday, June 14th, YIKES!! Trying not to scared!! I'm a patient at Florida Mayo clinic, so I'm in the best hands. Also, my dr has moved up my appointments to every 3 months. Now we'll see what bone marrow tells...UGHHH!