Yea, I had patch testing done. No allergies to things like personal care products, just my regular hayfever, cats, dogs. I already knew that I had those.
I agree, patch testing should obviously be done. It just sounded to me like your derm felt like allergies play or might play a big role in this. When you say "she wouldn't hear of anything until she ruled out an allergic reaction" and not try to test for e.g. bacterial and fungal infections, and she is seeing 2-3 people with EC a week, that to me would mean that a lot of those cases were actually caused by allergies.