Are you sure what you have is Acne and not some sort of other skin disease? That might be worth looking into.
A naturopath might be able to help you, look for one that knows a lot of thing like iridology, herbals, reflexology, ect.
You might also want to look at dermatology again if you're truly desperate. A different dermatologist might be able to help. Not every doctor or naturopath is the same - each have different talents and abilities and technology at their disposal. It may take some searching to find the right one for you. I went through 3 chiropractors before I found the one who could actually help me, but I didn't give up.