[ElaineM]

I forgot to mention a few other possibilities.
Have you changed any medication from brand name to the generic version lately?
One of my medications was changed from brand name to the generic version. I got a rash around my nose and mouth that 4 doctors could not resolve. I talked with a pharmacist at my local pharmacy. Although the drug itself was the same the generic version had a filler (binder) powder that was cheaper than the one in the brand name, but caused more allergies. I had it tested against my face with allergy testing and sure enough the generic version contributed to the rash, but the brand name did not. I told my doctor who filled out forms for the insurance company so they would pay for the brand name again. Problem solved. The rash went away.
Also our skin and other body parts change as we get older. Sometimes we become sensitive to things we were never sensitive to before. I became latex sensitive after I became a cancer patient !!!!!!!!!! I was not latex sensitive when I was younger or before cancer treatment. Anything with latex and even some other kinds of adhesives cause an instant rash !! What kinds of equipment does the staff where you are treated use? Does any of it have latex? You might want to consider allergy testing, not only for latex, but for other things as well.
The next suggestion is have you changed any cosmetics, soaps, household cleaners, laundry soaps and other things you use on a daily basis lately?
I have to be very careful about soap----------even soap that is supposed to be good for the skin. I can't use any soap or cleaning product with fragrance.
Perhaps you would like to see a good dermatologist for help too !!
I hope you solve the mystery soon, so you don't have to suffer any longer.