"Rash" comes and goes

I have noted in the last few weeks that I have two patches of bumps on either side of my urethral opening on my penis.  It is difficult to explain, but the bumps appear as two patches of raised skin that alomost look like poison ivy (kind of red) with some smaller bumps within the borders.  I saw my dermatologist who gave me numerous creams and ointments to try that only seemed to worsen the condition.  I explained that I wanted to be sure that I didn't have an STD, and he didn't seem to think it looked like one (but did say he could be wrong).
I stopped using anything a couple of days ago, and saw massive improvement yesterday (rash was effectively gone) - then a bit of a degredation today (looks irritated again).  They aren't painful, don't ooze or have anything that looks like fluid in them - just raised areas.  No hard borders, no real discoloration.  Look like welts.  
I had a battery of STD tests done at 1 month after my last relations that came back negative for Herpes, Syph, Gon, Chlamydia.  I do notice that cold complresses seem to relieve the symptoms almost entirely, but they come and go (sometimes worse than others).

Is there anything that you can think of (STD wise) that I should be concerned about?  Derm (and my PCP) said it doesn't look like any wart they've ever seen before, but wouldn't rule out 100%.  Doesn't seem that warts would get better and worse over a course of days (or hours).  

Thanks for any thoughts you can provide.

[H. Hunter Handsfield, M.D.]

With both your PCP and a dermatologist not coming up with a clear diagnosis, I certainly cannot do so.  Warts definitely do not fluctuate in prominence or appearance over a few days.  So given your description and your negative tests, I cannot imagine that any STD is the cause. Otherwise I cannot help; you need to just follow up with your own providers.

HHH, MD

[candy7260]

A related discussion, rashes was started.