Hi Mike, I have IGM MGUS (high IGM and low IGA and IGG) diagnosed in 2021. I am 69 years old and my IGM was also in the 300 range in 2021 and is now 543. Do you know what the determining factor was from the bone biopsy for the change in diagnosis to Waldenstrom’s? My hematologist told me that if my MGUS ever progressed it would most likely progress to Waldenstrom’s. I also began experiencing fatigue, weakness and shortness of breath this year and although my hematologist feels that a bone marrow biopsy is not necessary due to my IGM not being extremely high he said he would order one at my next visit if I wanted one. He thought my other lab work did not indicate a reason for my symptoms. Did you have other factors in your blood work indicating a possible anemia? If you are like most of us, developing chronic fatigue and weakness can be worrisome because it affects every aspect of our life. Has your doctor mentioned a treatment plan going forward? As to your question about vaccinations, I asked my hematologist about the Covid vaccine back in 2021 as I had not taken one and he stated that it would not be effective due to the high IGM and low IGA/IGG. I asked him if I were more at risk of becoming ill by being out in public than most people and he stated no. So I have opted not to take any vaccines although I am retired and not out in public very much except to go to the store or doctor appointments. I practice what my GP once told me- and that is to never touch my eyes, nose or mouth unless I have just washed my hands and that advice has served me well. If you would prefer to connect with me privately please let me know and I can provide my email address. Thank you and may God keep you under his protective wings.