No STD causes a "rash in the groin", or a rash anywhere that comes and goes like this. That includes herpes. I probably would not have thought to worry about HIV either. Further, I am sure this has nothing to do with your commercial sex adventure.
In any case, no online provider can provide better information than providers who have examined someone, especially when the problem is a rash and two dermatologists havne't been able to sort things out. I suggest following your dermatologist's advice. But whatever is going on is not an STD. (If we had a patient like you in my STD clinic, we wouldn't even take care of the problem. We would refer to a dermatologist.)
Sorry I can't help further. But put herpes and other STDs out of your mind.
Best wishes--- HHH, MD
I meant to say that the negative HIV tests prove you don't have it and that HIV cannot possibly have anything to do with this problem.
Thank you -- my desperation is mostly related to the fact that ever since the encounter I have manifested multiple and recurring genital symptoms. It's a daily effort to reassure myself to believe that I a)will not infect my wife with an std and b)this isn't a mildly symptomatic version of a true std. Multiple failed treatments and diagnoses have contributed to this fear too. I'm thinking, do I have diabetes or another similar immunosuppresive problem?
I don't care about the timing. It's a coincidence. No STD causes such a problem. You have nothing you can transmit to your wife. I haven't a clue about diabetes, but you don't describe anything that sounds like you are immunosuppressed.
Your dermatologist or other doctors are the only ones who can sort this out for you. This forum cannot. Sorry.