For the last 3 months I've been having a red, itchy/burning rash. It started on my lower back, but then traveled to my chest and now neck area. It's never in all 3 places at the same time, nor is it anyplace else. I haven't changed medications or detergents. My Dr's just shrug and suggest I go see a Dermatologist. I've tried Cortisone Creams and Antihistamines but neither work. Cold compresses do help the burning but it's making me crazy.
My nephew had an unexplained rash that drove him crazy. Saw doctors, dermatologists etc. turned out it was related to a gluten intolerance. He was about 45 when this started. He does not have MM . Maybe it is not related to myeloma.
I have SMM and of course MGUS before that since "09" but nothing to deal with like the rash you describe. Hopefully you will find them cause and cure. Keep fighting!