You may want to stop the Retin A and see if that helps. Again, as I said before....get some oregano oil from a quality healthfood store. That helps kill bacteria and candida.
Body Acne is always a sign that more bowel cleansing and Liver Flushing is in order.
I had bad Acne on my chest, neck, and back, but when I keep the bowels and liver clean, I have no breakouts at all.